Background to the study

Golden everlasting paper daisies in the genus Xerochrysum Tzvelev are iconic Australian native plants grown worldwide. The X. bracteatum (Vent.) Tzvelev species complex has been regarded as taxonomically confusing and in need of revision for over 60 years. Thirteen species are currently recognised in Xerochrysum, with an additional four species being added by Wilson (2017; endorsed by the Council of Heads of Australasian Herbaria for inclusion in the Australian Plant Census, but not yet available in that dataset) since the studies by Schmidt-Lebuhn et al. (2015), and species are found in all Australian states and mainland territories, as well as the highlands of Papua New Guinea (CHAH 2020a ; B. J. Conn, R. Banka, L. L. Lee, ‘Plants of Papua New Guinea’, see  http://www.pngplants.org). Xerochrysum includes some of the showiest and most widely grown of Australia’s native flora, yet taxonomic questions have persisted, alongside the widespread cultivation of many different cultivars, ‘varieties’ and ‘forms’, for over 60 years (Curtis 1956; Harden 1991; Flann 1998). First grown in England and Europe from the late 1700s (Andrews 1805), the type of Xerochrysum (as Xeranthemum bracteatum Vent.) was described by Ventenat (1803) from plants cultivated in the Empress Joséphine’s orangerie at Malmaison. Ventenat expressed reservations in his prelude (Ventenat 1803) that X. bracteatum was enlarging Linnaeus’ concept of Xeranthemum, and also saw taxonomic issues in the inclusion of the new species in Helichrysum Mill.; however, the species was soon transferred to this genus by Andrews (1805). The publication of Flora Australiensis (Bentham 1867) recognised a broadly circumscribed H. bracteatum Vent. subsuming H. viscosum Sieber ex Spreng. (Sprengel 1826), H. bicolor Lindl. (Lindley 1835), H. acuminatum (Link) Sweet (Sweet 1826), H. papillosum Labill. (Labillardiere 1806), H. banksii A. Cunn. ex DC. (de Candolle 1838), and H. macrocephalum A. Cunn. ex DC., a species described as growing on ‘the sandy shores of Moreton Bay’ (de Candolle 1838, p. 188). Bentham’s work (1867) remained the standard reference for over 120 years despite increasing taxonomic uncertainty (Curtis 1956; Burbidge 1970; Willis 1973). Anderberg (1991) drew on the prominent involucral bracts, hereafter referred to as phyllaries, and the large glabrous cypselae with barbellate pappus bristles to erect Bracteantha Anderb. & Haegi., but this was shown to be illegitimate (Bayer 2001) owing to the publication of Xerochrysum (Tzvelev 1990, cited in Bayer 2001) the previous year.

Phyllary indumentum characters have been informative when delimiting species of Xerochrysum (Flann 1998; Buchanan 2004; Wilson 2017) and, combined with root-system characters, have been used to separate Xerochrysum into two subgeneric groups (Wilson 2008, 2017). Initially, the two groups comprised the ‘X. bracteatum group’ with a multi-veined claw, and the single-veined ‘X. leucopsideum group’ (Wilson 2008). In the recent partial revision of Xerochrysum, Wilson (2017) modified the concept by defining the ‘X. milliganii (Hook.f.) Paul G.Wilson group’ to contain those species with a single-veined claw, removing Helichrysum leucopsideum DC., which had been shown to be more closely related to some species of Coronidium Paul G. Wilson (Schmidt-Lebuhn et al. 2015). Wilson (2017) recognised four new species previously included in X. bracteatum sens. lat. and raised further taxonomic questions. Currently, X. bracteatum is a variable species, possibly including several unrecognised taxa, and distributed in a broad arc from the highlands of Papua New Guinea to the Eyre Peninsula in South Australia (Wilson 2017; Australia’s Virtual Herbarium, see  http://avh.chah.org.au, accessed 12 September 2020).

Taxonomic uncertainty

Most specimens of Xerochrysum in Australian herbaria have been determined to species or an accepted phrase-name taxon, yet limits of many of them remain unclear with consequent inconsistent application of names. Past species limits applied to Xerochrysum have drawn exclusively on morphological differences, and this approach has been unable to find disjunctions among some populations of polymorphic X. bracteatum (the X. bracteatum complex) occurring across over 8000 km² in eastern and southern Australia. For example, collections from the Barrington Tops National Park in NSW, occurring in distinct populations with white or yellow phyllaries, are treated as a separate entity by herbarium NE but have been variously determined by other Australian herbaria as either X. bracteatum sens. lat., X. sp. Glencoe (M. Gray 4401) NE Herbarium, X. sp. New England (L. M. Copeland 3731) NE Herbarium, or X. bracteatum subsp. barringtonense Paul G. Wilson MS (Australia’s Virtual Herbarium, see  http://avh.chah.org.au; New South Wales Flora Online, see  http://plantnet.rbgsyd.nsw.gov.au/floraonline.htm).

Taxonomic uncertainty is not limited to the X. bracteatum species complex. Xerochrysum boreale Paul G.Wilson is a recently described perennial from northern Australia, with a scattered distribution across the northern Pilbara and the Kimberley in Western Australia and the northern end of the Northern Territory (the ‘Top End’), occurring in a variety of habitats including coastal sands, seasonal swamps and sandstone escarpments. Not all specimens of X. boreale were considered distinguishable from Pilbara populations of X. interiore Paul G.Wilson (Wilson 2017; FloraBase – the Western Australian Flora, see  https://florabase.dpaw.wa.gov.au/, accessed 29 August 2019), and one specimen cited as X. boreale came from mulga–eucalypt woodland in southern Queensland, well beyond its stated distribution (Wilson 2017).

Morphological variation has also been reported between the mainland populations and the Tasmanian populations of X. subundulatum (Sch.Bip.) R.J.Bayer, a subalpine to alpine species with disjunctions in distribution in Tasmania, Victoria and New South Wales (Wilson 2017). Collections from wetlands in Tasmania, Victoria and New South Wales have scabridulous outer abaxial phyllary surfaces but otherwise share similar morphological and ecological characteristics with X. palustre (Flann) R.J.Bayer, a slender, erect perennial occurring in lowland wetlands (Flann 1998). The scabridulous phyllary indumentum character has seen these populations included in X. subundulatum by herbaria HO, CANB and NSW.

Putative new taxa

In the 1970s, Nicholas Lander applied informal groupings (e.g. ‘inland form’, ‘coastal ecotype’, ‘radical leaves’) on determination slips and specimen annotations, to some populations of X. bracteatum sens. lat. [as Helichrysum bracteatum] but did not proceed to publication. Currently, Australian herbaria recognise phrase names for the following six putative new taxa in Xerochrysum (CHAH 2020b ; Australia’s Virtual Herbarium, see  http://avh.chah.org.au): (1) X. bracteatum subsp. Mount Elliot (A.R.Bean 3593) Qld Herbarium; (2) X. sp. Glencoe (M.Gray 4401) NE Herbarium; (3) X. sp. Mount Merino (S.T.Blake 22869) NE Herbarium (synonym: X. bracteatum subsp. Mount Merino (S.T.Blake 22869) Qld Herbarium); (4) X. sp. New England (L.M.Copeland 3731) NE Herbarium; (5) X. sp. North Stradbroke Island (L.Durrington 675) NE Herbarium (synonym: X. bracteatum subsp. North Stradbroke Island (L.Durrington 675) Qld Herbarium); and (6) X. sp. Point Lookout (I.R.Telford 12830) NE Herbarium. Examination of specimens at NSW and CANB suggest Lander’s ‘inland form’ may represent the recently described X. interiore (Wilson 2017), whereas the ‘coastal ecotype’ corresponds to X. sp. North Stradbroke Island and possibly de Candolle’s (1838) H. macrocephalum, whereas ‘radical leaves’ corresponds to X. sp. Glencoe.

Xerochrysum has been the subject of many unpublished taxonomic concepts, such as the proposed splitting of the genus and erection of Diemenica to include the ‘X. milliganii group’ (annotated on some specimens of CANB; T. L. Collins, pers. obs., 2017). Within Xerochrysum, unpublished taxa and combinations include X. leucopsideum ined. (Wilson 2008), X. bracteatum subsp. barringtonense ined. (New South Wales Flora Online, see  http://plantnet.rbgsyd.nsw.gov.au/floraonline.htm) and X. bracteatum subsp. dromedariense ined., X. bracteatum subsp. eriophyllum ined., and X. bracteatum subsp. lanatum ined. (the last three annotated on some specimens at AD, BRI, CANB, MEL, and NSW; T. L. Collins, pers. obs., 2017–2019).

Wilson (2017) did not attempt to resolve the putative new taxa of Xerochrysum that have been under study for more than 10 years at the University of New England (Duley 2007; N.C.W. Beadle Herbarium (NE) database, see  https://ncw-beadleherbarium.une.edu.au/). Phenetic analyses using continuous and discrete characters had suggested that there were up to seven distinct entities in the X. bracteatum sens. lat. species complex from eastern Australia (Duley 2007). The discovery of the putative new entity X. sp. Mount Kaputar, not included in the phenetic analyses, suspended publication of the results.

The Western Australian endemic X. macranthum (Benth.) Paul G.Wilson has a distribution from Geraldton to Albany and occurs in diverse habitats from dry woodland to forest swamps, mountain peaks and coastal limestone heath (Wilson 2017; Australia’s Virtual Herbarium, see  http://avh.chah.org.au). Most populations of X. macranthum have white phyllaries, yet, in the north of the range, yellow-phyllaried populations occur. Populations of X. macranthum restricted to mountain tops in the Stirling and Porungurup ranges in south-western Western Australia, an area known for very high endemism (Crisp et al. 2001), have broader leaves than do those at lower altitudes and latitudes, and morphological differences have been maintained under cultivation (G. J. Keighery, pers. comm., cited in Wilson 2017).

Putative hybrids

Species delimitation in complex groups can be complicated by the presence of hybrids, apomixes and polyploidy (Depypere et al. 2009; Schilling 2011). Wilson speculated that some populations of X. bracteatum sens. lat. were intergrading or hybridising with either X. papillosum (Labill.) R.J.Bayer, Xerochrysum halmaturorum Paul G.Wilson, X. interiore or X. boreale, and were morphologically similar to X. bicolor (Lindl.) R.J.Bayer and X. macranthum, but these hypotheses were not tested with molecular data (Wilson 2017). Xerochrysum sp. Blackfellows Gap (N.T.Burbidge 6926; currently treated as a synonym of X. subundulatum; CHAH 2020a ), has been applied to specimens from the Brindabella Ranges on the Australian Capital Territory–New South Wales border. Collections assigned to this entity have unusual leaf and stem indumentum, and have been suggested to be hybrids between X. subundulatum and X. viscosum (Sieber ex DC.) R.J.Bayer (Burbidge 1970), or a putative new species (Wilson 2017).

Xerochrysum viscosum is a woodland species broadly distributed in south-eastern Queensland, central and eastern New South Wales, the Australian Capital Territory and Victoria. The presence of viscid glands and narrow leaves has been regarded as a distinctive feature of X. viscosum (Harden 1991; Wilson 2017). Some collections with leaf width intermediate between X. viscosum and X. bracteatum sens. lat. have been treated as hybrids between these two species (Wilson 2017).

Populations of X. bracteatum sens. lat. in the Barrington Tops New South Wales have been recorded with either white, white and pink, or yellow phyllaries. Intermediates with pale yellow or orange phyllaries, suspected to be hybrids, have been seen where these differently coloured populations co-occur (J. R. Hosking, pers. comm., 2018).

The final hypothesis of hybridisation that should be mentioned is that various cultivars of X. bracteatum (with slightly curved phyllaries coloured pink, orange, purple and red) are widely thought to have been developed in Germany in the 1800s and 1900s, from hybridisation with South African species of Helichrysum (Rymer 2006; Russell 2015). Evolutionary analyses have suggested that breeding compatibility between Xerochrysum and African Helichrysum is unlikely because of the large phylogenic distance between them (Galbany-Casals et al. 2014; Nie et al. 2016). A recent study of gene flow and ancestry analyses showed that some colourful cultivars are hybrids between eastern Australian X. bracteatum and Western Australian X. macranthum (Collins et al. 2021).

Resolution of the longstanding taxonomic uncertainty in Xerochrysum will facilitate study of evolutionary relationships and ecology of members of the genus, provide a sound basis for assessment of conservation status, allow accurate curation of herbarium collections and identification within the genus, and highlight taxa with particular horticultural potential. The present study applies molecular and morphological approaches to test species limits and find evidence of common ancestry or recent gene flow among populations of Xerochrysum from across Australia. Identification of corresponding molecular and morphological discontinuities would support taxon boundaries indicative of separately evolving lineages, consistent with the unified species concept (De Queiroz 2007). Specifically, this study aims to test the status of formal and informal (phrase name) taxa and putative hybrids within Xerochrysum. Taxa recognised here will be described and diagnosed using morphology, congruent with the molecular data.

Study group

The current study uses the species of Xerochrysum defined by Wilson (2017) and other formally accepted phrase name and manuscript taxa (Table 1; CHAH 2020a ), but also includes informal phrase names in use at NE (Table 2; N.C.W. Beadle Herbarium (NE) database, see  https://ncw-beadleherbarium.une.edu.au/). This approach ensured testing of the current species limits against multiple hypotheses of putative new entities. During the course of fieldwork, populations in the Sydney Basin and New South Wales South Coast bioregions were seen to have leaf indumentum and habit distinct and different from populations in the New England Tablelands Bioregion, and the former are hereafter being referred to as X. bracteatum sens. str., and the latter as X. sp. Northern Tablelands. Populations currently included in the X. bracteatum complex and of uncertain grouping are referred to as X. bracteatum sens. lat. Additional informal phrase names were used to group populations outside the Sydney Basin and New South Wales South Coast, and they were included in analyses under these informal phrase names (Table 2). Populations similar to Xerochrysum palustre but with scabridulous phyllaries were tentatively referred to as X. aff. palustre.

Table 1.

Formally accepted Australian Plant Census (CHAH 2020a ) phrase name taxa of Xerochrysum.

Table 2.

Informal phrase name taxa applied to some Xerochrysum.

Field collection

Field collection was essential to gather high-quality specimens, as well as propagules, and tissue for DNA extraction with sufficient sampling density. Many gatherings of Xerochrysum in Australian herbaria, including many type specimens, are fragments and comprise just the inflorescence and upper cauline leaves and do not have the base of the plants, lower leaves, root-system, or cypselae (T. L. Collins, pers. obs., 2017–2020). Sites were prioritised to collect topotypes, and other sites known from specimen collections <20 years old (Australia’s Virtual Herbarium, see  http://avh.chah.org.au) to increase the likelihood of relocating sites. Fieldwork was conducted between November 2017 and March 2019. Owing to record-low rainfall and extreme drought (Bureau of Meteorology 2020), no fieldwork was conducted in western NSW and western Queensland. Descriptions of habit, habitat and associated plants, topography, number of plants in the population, and soil were recorded at each collection site. Herbarium specimens, leaf material for DNA extraction, cypselae and cuttings were collected when found, and when permit conditions allowed. When available, leaf material from at least five plants spaced ~5 m apart was placed immediately in nylon bags and then in sealed containers with silica gel desiccant (Si gel). Herbarium specimens were pressed in the field, and air-dried at ~16°C and 16% relative humidity before freezing for 1 week at ~−30°C for herbarium biosecurity. A complete list of gatherings used in the present study can be found in  Supplementary Table S1 (SB21014_AC.PDF).

To broaden sampling, additional sources were accessed. Small quantities of leaf were taken from Si gel collections at the N.C.W. Beadle Herbarium (NE) or from herbarium specimens. Si gel collections of X. bracteatum sens. lat. and X. subundulatum were made available for analysis by the Terrestrial Ecosystem Research Network (TERN). Collections of cypselae were accessed from the South Australian Seed Conservation Centre, Australian PlantBank, Royal Tasmanian Botanical Gardens, and the Australian National Botanic Gardens. An extended network of colleagues, friends and volunteers collected material when available and permit conditions allowed.

Collections were made under the following permits and licences: Queensland Government permit number WITK18639817; New South Wales permit number SL100305; Northern Land Council permit number 81511; Northern Territory Government permit number 62139; South Australia permit number G25787-3; Tasmania permit number TFL17334; Western Australia permit number SW019464 and Regulation 4 number CE005748.

Plant propagation and cultivation

Fruits obtained during field collection and from seedbank collections were sown in a commercial seed-raising medium (Searles Seed Raising Mix, JC & AT Searle Pty Ltd, Kilcoy, Qld, Australia) and germinated in a refrigerated incubator (Model: RI250SG, Thermoline Scientific Equipment Pty Ltd, Sydney, NSW, Australia), set at 22°C day, 12°C night and 10-h–14-h day–night with fluorescent lighting. Germinated seedlings were transplanted to a soil-less potting medium (Searles Professional Potting Mix, JC & AT Searle Pty Ltd, Kilcoy, Qld, Australia). Seedlings and plants were grown in an air-conditioned glasshouse maintaining the maximum temperature below 25°C.

Small numbers of seedling transplants were collected when fruits were unavailable. Seedlings were removed from soil, wrapped in damp paper inside a plastic bag and kept cool. On return to the university, seedlings were potted in soil-less potting media and kept under intermittent mist with bottom heat for ~2 weeks before transferring to the air-conditioned glasshouse.

Phenetic analyses of morphology

Fourteen quantitative and two qualitative characters (Table 3) were recorded from 97 herbarium specimens representing all study group taxa (Table 4) except for the ‘X. milliganii group’. The ‘X. milliganii group’ was excluded on the basis of the distinctive phyllary morphology, thereby focussing the phenetic analysis on the X. bracteatum complex. Live plants were grown to provide fresh material for comparison with dried specimens. Use of herbarium specimens for phenetic analyses gave access to a broader range of populations and putative entities. The choice of characters was based on preliminary examinations of herbarium specimens, cultivated plants, plants in the field, and published characters applied to species of Xerochrysum (Flann 1998; Wilson 2017). Quantitative characters were used in preference over qualitative characters, to avoid imposing artificial or arbitrary boundaries on any morphological variability. Means were calculated from at least three measurements per specimen for all characters except length of cauline leaf mucro (Table 3, Character 6). Cypselae length and width, not including pappus, were measured using the eyepiece graticule in a Leica 7.5 stereomicroscope, calibrated using a ruler with a half-millimetre scale. Leaf-width dimensions on mature leaves were measured using a ruler with a half-millimetre scale. Leaf length was not measured because of the imprecision of measuring folded and curved leaf specimens. Phyllary apex angle was measured using the angle tool in ImageJ (ver. 1.52a, see  https://imagej.nih.gov/ij/download.html; Schneider et al. 2012) on images taken on an iPhone 6 camera (Apple Inc., Cupertino, CA, USA). Stereome and phyllary lamina vascular bundles were observed using a Leica 7.5 stereomicroscope with transmitted light. Scanning electron microscopy (SEM) was used to examine sections of mature leaves mounted onto 12.5-mm aluminium SEM stubs with double-sided carbon tape, and included the margin, apex and midvein for both adaxial and abaxial surfaces. Mounted samples were placed on an angled stage and gold-coated using a JEOL MP-19020NCTR NeoCoater (JEOL Ltd, Tokyo) for 6 min, rotating the stage 60° laterally every 2 min. Specimens were examined and images captured with a JEOL JSM-6010LA Analytical SEM (JEOL Ltd, Tokyo) at 10 kV. A series of images was taken at 75× and 100× magnifications. Trichome density was recorded from SEM using a stencil template representing 0.25-mm² leaf area and the cell-counter tool in ImageJ (ver. 1.52a; Schneider et al. 2012). Apical-cell diameter and length of cauline leaf-tip mucro were measured on SEM micrographs with a ruler with a half-millimetre scale calibrated against the micrograph scale bar.

Table 3.

Characters used in morphometric analyses of taxa and putative entities of Xerochrysum.

Table 4.

Geographic subsets of species and entities of Xerochrysum used in phenetic analyses of morphology.

Data were entered into PATN (ver. 3.12, see  https://patn.org/; Belbin 1993). All characters were weighted equally for cluster and ordination analysis to examine patterns of similarity and difference among individuals. Three-dimensional ordination fusing semi-strong hybrid multidimensional scaling (SSH MDS) was conducted using the Gower metric association measure (Gower 1971), a widely used method that involves range-standardisation of data for each character. SSH MDS has a demonstrated effective recovery of phenetic clusters (Faith et al. 1987; Holman et al. 2003; Plunkett et al. 2013). The ordination analyses were produced with 250 random starts and 500 iterations. The principal component correlation (PCC) analysis in PATN uses multiple linear regressions to fit each selected variable independently into the ordination space (1, 2 or 3 dimensions). The result is a set of coordinates that represents the tip of the vector of the variable. An r-squared value provides some estimate on how good the fit was. Variables with PCC values >0.7 were considered to contribute strongly. Phenograms were produced from classification analysis using the unweighted pair-group method with arithmetic mean (UPGMA) agglomerative hierarchical fusion (β = −0.1). Subsets of the morphometric data (Table 4) representing broad distribution patterns of Xerochrysum across Australia (i.e. north, south, east and west) were analysed using PATN as above, to assess the extent to which co-located species and putative entities can be distinguished by morphometric analysis. Ordinations were plotted in R (ver. 3.6.1, R Foundation for Statistical Computing, Vienna, Austria) through RStudio (ver. 1.0.153, RStudio PBC, Boston, MA, USA, see  https://rstudio.com/) with species and putative entities being designated unique colours.

Sample selection for molecular analyses

Sampling density was not applied uniformly across all collection sites. For example, the long-standing phrase name entity X. sp. Mount Merino, currently included in X. bracteatum, has a perennial life form, shrub-like habit, very large capitula, dense tomentose leaf indumentum, and is known only from cliff-edge habitats on the margins of Nothofagus moorei closed forests in northern New South Wales and south-eastern Queensland. The distinct morphology and limited distribution of X. sp. Mount Merino suggests a rare and restricted ‘narrow endemic’, and because of finite resources, only two samples were sequenced. The morphologically distinctive Tasmanian alpine endemics X. collierianum and X. milliganii were limited to three samples each. Greater sampling density was applied to test species limits, shared common ancestry and recent gene flow between populations and putative hybrids with less certain boundaries occurring sym- or parapatrically. Sampling locations for all species and putative entities is shown in Fig. 1. Details of the rationale, used to include the populations representing species and putative entities examined with molecular data, can be found in the Supplementary material under the subheading, ‘Rationale for sample selection in molecular analyses’.

Fig. 1.

Sample locations for Xerochrysum. Labelled ellipses indicate the distribution of samples included in X. bracteatum sens. lat., X. viscosum, X. macranthum, X. interiore and X. boreale. Clockwise, starting at Cape York Peninsula (the north-eastern tip of Australia): X. bracteatum sens. lat. (red circles), X. sp. North Kennedy (pale green circles), X. sp. Mount Elliot (pale green star), X. sp. North Stradbroke Island (dark blue circles), X. sp. Mount Merino (dark green circles), X. sp. Northern Tablelands (grey circles), X. sp. New England (yellow circles), X. sp. Point Lookout (pink star), X. sp. Glencoe (brown circles), X. sp. Barrington Tops (purple circles), X. aff. palustre (pink triangles), X. sp. Flinders Range (orange circles), X. subundulatum (gold triangles), X. palustre (green triangles), X. collierianum (blue triangles), X. milliganii (yellow triangle), X. alpinum (white triangle obscured by X. milliganii).

DArTseq genotyping, population genetic structure and ordination

DNA extraction and DArTseq reduced representation sequencing were conducted by Diversity Arrays Technology Ltd, using the DArTseq approach with medium marker density and proprietry DNA purification (Kilian et al. 2012). This method can be optimised for detecting gene flow in organisms lacking a reference genome (Al-Beyroutiová et al. 2016; Egea et al. 2017; Alam et al. 2018). Details of the DArTseq approach can be found in the Supplementary material under the subheading, ‘DArTseq genotyping’.

Exploratory filtering of DArTseq loci at different levels of stringency confirmed only minor effects on the clustering of samples in PCoA. Filtering loci and individual call rate using the function gl.filter.callrate (Gruber et al. 2018) excluded samples with >20 and >30% missing data respectively, ensuring minimal missing data, inclusion of most samples, and maximal computational efficiency.

Genetic divergence and diversity were estimated for each taxon in R (ver. 3.6.1). Expected heterozygosity and inbreeding estimation F _IS were estimated using the adegenet package H _S function and inbreeding function respectively (ver. 0.5-11, see  https://cran.r-project.org/package=adegenet; Jombart and Ahmed 2011). Observed heterozygosity was calculated using the dartR function gl.report.heterozygosity (ver. 2.0.3, see  https://CRAN.R-project.org/package=dartR; Gruber et al. 2018) and means were calculated. Nei’s genetic divergence coefficient G _ST is analogous to F _ST for bi-allelic loci (Nei 1973, p. 3322). F _ST for species and cultivars was calculated using the hierfstat package fstat function (ver. 0.5-11, J. Goudet and T. Jombart, see  https://CRAN.R-project.org/package=hierfstat, accessed 12 May 2022).

Underlying data structure and visualisation of genetic differences for all Xerochrysum samples was undertaken by principal coordinate analysis (PCoA) using the function gl.pcoa in the dartR package (Gruber et al. 2018). Principal coordinate analysis (Gower 1966) produces low-dimensional coordinates from a derived distance matrix that summarises as much as possible the variance in the original data (Faraway 2012). Exploratory filtering of DArTseq loci at different levels of stringency confirmed only minor effects on the clustering of samples in PCoA. Filtering loci and individual call rate using the function gl.filter.callrate (Gruber et al. 2018) excluded samples with >20 and >30% missing data respectively, ensuring minimal missing data, inclusion of most samples, and maximal computational efficiency. Subsets of the DArTseq samples (Table 5) representing large clusters in the PCoA (Fig. 2) were produced from the raw data, filtered to exclude samples with loci call rates missing >40% and individual call rates missing >40%, to allow examination of finer-scale genetic differences (Rutherford et al. 2018). Individual samples were identified in each PCoA by using the function gl.pcoa.plot, with the label argument set to ‘interactive’ (Gruber et al. 2018).

Table 5.

Subsets used to examine large groups within the ‘allXerochrysum’ PCoA of molecular data for Xerochrysum.

Fig. 2.

Principal coordinate analysis Axes 1 and 2 of 2486 single-nucleotide polymorphism loci representing all species of Xerochrysum (except X. collierianum) and putative entities. Each dot represents an individual sample, coloured by population. Groups are numbered as in Table 9.

Bayesian genetic clustering

To assess putative hybridisation and account for fine-scale variation, ‘Bracteatum’ and ‘Boreale’ subsets of the sequence data identified using PCoA (Table 5, Fig. 2) were investigated using the Bayesian Monte Carlo Markov-chain (MCMC) procedure implemented in STRUCTURE (ver. 2.3.4, see  https://web.stanford.edu/group/pritchardlab/structure_software/release_versions/v2.3.4/html/structure.html; Pritchard et al. 2000; Beaumont et al. 2001; Falush et al. 2003). The program optimises the allele frequencies that characterise K genetic clusters based on a model assuming random mating and linkage disequilibrium within ancestral populations. If a model allowing admixture is used, each individual is assigned a proportion of ancestry derived probabilistically from each ancestral population. This approach is appropriate because it does not assume ancestry a priori. We used the default setting for RECESSIVEALLELES = 0, treating all samples as diploid, as diploids comprised the majority of samples (Laport et al. 2016). STRUCTURE has previously been tested in several diploid–polyploid species complexes (D’hoop et al. 2010; Stöck et al. 2010; Moore et al. 2014), with little effect of the RECESSIVEALLELES flag observed for codominant markers (Moore et al. 2014; Meirmans 2019). Simulations have shown STRUCTURE to be robust in detecting population structure in mixed-ploidy samples (Stift et al. 2019). Estimation of ancestry clusters was performed on 10 replications using K = 1–16 for the ‘Bracteatum’ group, and 10 replications using K = 1–10 for the ‘Boreale’ group and species and putative entities associated with X. sp. Blackfellows Gap. Higher values of K were tested for the ‘Bracteatum’ group because of the greater number of putative entities. Values of K best supported by the data were identified by plotting the natural logarithm of the likelihood and were used to assess the support for each value of K following the reasoning outlined by Pritchard et al. (2000). Caution must be taken when interpreting large STRUCTURE barplots because the algorithm parsimoniously explains variation among individuals and does not provide a parametric model of divergence and admixture (Lawson et al. 2018). To address this issue, we examined a further four subsets of the data, including (1) X. sp. Barrington Tops, X. sp. Glencoe, X. sp. New England and X. sp. Point Lookout, (2) X. bicolor, X. halmaturorum and X. sp. Lofty Ranges, (3) X. boreale, X. sp. Mount Elliott, X. sp. North Kennedy, X. sp. Fly Point and X. sp. Walker Point, and (4) X. bracteatum sens. lat. (putative weedy populations), X. sp. Northern Tablelands, X. sp. North Stradbroke, and X. sp. Chinchilla. Violations of the model assumptions can occur by inclusion of samples that are close relatives, population divergence owing to isolation-by-distance, subtle subdivisions nested within diverged groups, and recent genetic bottlenecks, potentially leading to misinterpretation of the results (Lawson et al. 2018). We also applied an alternative to estimating the optimal number of K clusters, by cautiously describing the clustering results over several values of K in relation to known natural history data (Funk et al. 2020).

Field collections

Collections were made at 116 sites, with 89 vouchers bearing mature cypselae. Photographs of habit and habitat were taken, and notes on associated species and soil substrate were collected.

Phenetic analyses of morphology

Indumentum and trichome length observed on cultivated plants was consistent with that of dried herbarium specimens, although spreading trichomes on live plants became appressed on the dried specimens, an artefact that was likely due to the pressing and drying process. Indumentum on cauline leaves was observed to vary among species and entities, with differing states being described as cobwebby, hispidulous, hispid, hirsute, felted, pilose, tomentose, and woolly, composed of septate trichomes (Fig. 3), sometimes with flagelliform apices (see Fig. 4), or with sessile or stipitate glands. Phenetic analysis of all 97 specimens of Xerochrysum using 16 characters produced mixed groups loosely corresponding to named species and putative entities in most cases ( Supplementary Fig. S1 (SB21014_AC.PDF)); viz, X. halmaturorum, X. viscosum, X. sp. Glencoe, X. sp. North Stradbroke Island, X. bracteatum, X. sp. Mount Elliott, X. sp. North Kennedy, X. boreale, X. sp. Point Lookout, X. sp. New England, and X. sp. Northern Tablelands. Entities not forming clusters included X. bicolor, X. sp. Mount Kaputar, X. sp. Lofty Ranges, X. sp. Barrington Tops, X. sp. Mount Merino, X. macranthum, X. sp. Porongurup, and X. papillosum. Ordinations based on subsets of the data broadly corresponding to northern, southern, eastern and western distribution showed tighter clustering, but again groups were incomplete and somewhat mixed (Fig. 5).

Fig. 3.

Indumentum variation among species of Xerochrysum. White arrows indicate stipitate glands in a–g. Leaf surface: (a–c) adaxial; (d–g) abaxial. (a) Hispidulous and with glands (X. bracteatum sens. str., T.L.Collins 1005); (b) hispid and with glands (X. sp. Barrington Tops, T.L.Collins 1046); (c) hirsute to pilose, and with glands (X. sp. Point Lookout, T.L.Collins 958); (d) with glands (X. bracteatum sens. str., T.L.Collins 1005); (e) hirsute and with glands (X. sp. Barrington Tops, T.L.Collins 1046); (f) pilose and with glands (X. sp. Point Lookout, T.L.Collins 958); (g) stipitate glands on abaxial leaf surface (X. bracteatum sens. str., T.L.Collins 1005). Scale bars: 0.5 mm (a–f); 100 μm (g).

Fig. 4.

Flagelliform trichomes and stipitate glands found on some species of Xerochrysum. Arrow with tail indicates stipitate gland; arrow without tail indicates septate trichome with flagelliform apex (cauline leaf adaxial surface, X. macsweeneyorum, T.L.Collins 957). Scale bar: 100 μm.

Fig. 5.

Semi-strong hybrid multidimensional scaling ordinations of morphological characters on subsets of species and putative entities of Xerochrysum representing broad distribution patterns across Australia (Table 4). (a) Northern; (b) southern; (c) eastern; (d) western. Each ball represents an individual sample, coloured by species or putative entity.

Leaf trichome density, in particular the density of glands on the leaf adaxial surface, had the highest PCC values, indicating that they were the most informative characters in the phenetic analyses ( Supplementary Tables S2–S7 (SB21014_AC.PDF)). Absence or near absence of non-glandular multicellular trichomes on the leaf abaxial surface was recorded on X. bracteatum sens. str., X. sp. Barrington Tops with white phyllaries (yellow-phyllaried plants have multicellular trichomes), X. bicolor, X. halmaturorum, X. sp. Lofty Ranges, X. interiore, X. macranthum, X. sp. Walker Point and X. viscosum (Tables 6–8). Absence or near absence of glands on the leaf abaxial midvein was recorded on X. boreale, X. sp. Fly Point, X. sp. North Kennedy, and X. sp. Walker Point (Tables 6–8). A summary of the morphometric data is available as Supplementary material to this paper ( Supplementary Table S8 (SB21014_AC.PDF)).

Table 6.

Summary of morphological observations seen in species and putative entities of Xerochrysum in the X. milliganii Group based on herbarium specimens and cultivated plants.

Table 7.

Summary of morphological observations in species and putative entities of Xerochrysum included in the ‘Bracteatum’ group, based on herbarium specimens and cultivated plants.

Table 8.

Summary of morphological observations seen in species and putative entities of Xerochrysum included in the ‘Boreale’ group, based on fieldwork, herbarium specimens and cultivated plants.

Examination of 15 specimens of X. bracteatum sens. lat. collected from the eastern and western highlands of Papua New Guinea and held at CANB showed large variations in leaf and stem indumentum, but overall similarity with populations of X. sp. North Kennedy and X. sp. Mount Elliott. A densely tomentose leaf indumentum, composed of septate trichomes and stipitate glands, was seen on both abaxial and adaxial surfaces. Six collections dating from 1954 to 1968 seemingly have no glands, possibly because of use of EtOH during specimen preservation.

Scanning electron micrographs

Stipitate or sessile glands were seen on most leaves dried for SEM (Fig. 4, S2–S9). Flagelliform trichomes, with filaments extending from the apical cell, were seen on many species and putative entities (Fig. 4, S10, S11). The filament, and eventually the trichome, appeared to readily abrade away to retain the trichome base and forming a hispid indumentum. Complete removal of the trichome base was observed on some species (e.g. X. sp. North Stradbroke Island,  Supplementary Fig. S4b (SB21014_AC.PDF)) causing a ‘trichome-scar’.

Examination of fresh leaves from cultivated plants confirmed that stipitate or sessile glands occur on all Xerochrysum either on adaxial or abaxial surfaces, or on both surfaces. Presence or absence of multicellular trichomes on cauline leaf abaxial surfaces varied between species and putative entities (Tables 7, 8). White phyllary colour seen in some X. sp. Barrington Tops populations covaried with the near absence of septate trichomes on the cauline leaf abaxial surface (Fig. 6e,f), as well as the much larger cotyledon size than in X. sp. Barrington Tops populations with yellow phyllaries.

Fig. 6.

Comparative morphology of phyllary colour, cotyledon size and cauline leaf abaxial indumentum for Xerochrysum sp. Barrington Tops populations. (a, c, e) White phyllaries T.L.Collins 1043; (b, d, f) yellow phyllaries T.L.Collins 1046. Scale bars: 1 cm (d, for c and d); 100 μm (f, for e and f).

DArTseq genotyping, population genetic structure and ordination

A total of 555 Xerochrysum samples were sequenced using the DArTseq method (Kilian et al. 2012). Fourteen of these failed to sequence and provided no data, including all X. collierianum samples. The sequence data partition contained 541 samples, with 47 207 loci representing all named species of Xerochrysum (except X. collierianum) and putative entities (hereafter: ‘allXerochrysum’). Filtering ‘allXerochrysum’ on locus and individual call rate >20 and >30% missing data respectively reduced the dataset to 524 samples and 2486 loci.

Observed heterozygosity was slightly lower than expected for most taxa and populations ( Supplementary Table S9 (SB21014_AC.PDF)). All taxa had a positive F_IS indicative of reduced heterozygosity, with less densely sampled populations having both higher expected and observed heterozygosities than did the larger groups. Very high values of F_ST (>0.4) were obtained for X. bicolor, X. boreale, X. halmaturorum, X. palustre, X. aff. palustre, X. papillosum, X. sp. Lofty Ranges, and X. sp. New England ( Supplementary Table S9 (SB21014_AC.PDF)). Pairwise F_ST comparisons among X. bicolor, X. halmaturorum and X. sp. Lofty Ranges indicated a gradual increase in genetic divergence between populations as distance between populations increased ( Supplementary Table S11 (SB21014_AC.PDF)). Populations of X. halmaturorum on Kangaroo Island showed the greatest level of divergence (0.593–0.599) from Tasmanian X. bicolor (0.222–0.313). Pairwise F_ST comparisons among populations of X. sp. North Kennedy, X. sp. Mount Elliott, X. sp. weedy, and X. sp. North Stradbroke Island indicated similar levels of genetic divergence among populations of X. sp. North Kennedy on the Atherton Tablelands (0.182–0.201), and between Atherton Tablelands populations and those in the Paluma Ranges and X. sp. Mount Elliott at Mount Elliott (0.137–0.214;  Supplementary Table S13 (SB21014_AC.PDF)).

The first two axes in the PCoA of ‘allXerochrysum’ (Fig. 2, Table 9) explained 29.6% of the genetic variation and showed distinct separation of some taxa. Axis 1 clearly separates X. subundulatum (Fig. 2, Cluster 7) and the rest of X. milliganii group from all other species and putative entities of Xerochrysum. Xerochrysum aff. palustre (Cluster 6) is disjunct and separate from X. palustre sens. str. (Cluster 5), X. milliganii (Cluster 4) and X. alpinum (Cluster 3). Axis 1 also separates X. sp. Glencoe (Cluster 12) from other species and putative entities of Xerochrysum. Axis 2 of ‘allXerochrysum’ (Fig. 2) shows X. sp. Porungurup, X. sp. Forests and X. sp. Limestone as a distinct group (Cluster 1) separated from X. macranthum (Cluster 2).

Table 9.

Taxon and putative entity clusters from principal coordinate analysis of 2486 single-nucleotide polymorphism loci representing all species of Xerochrysum (except X. collierianum).

The large subset ‘Bracteatum’ PCoA Axes 1 and 2 (Fig. 7a ) showed 23.4% of the genetic variation and all species and putative entities formed distinct clusters except for X. papillosum and X. viscosum. ‘Bracteatum’ PCoA Axes 1 and 3 (Fig. 7b ) showed separation of X. papillosum from X. viscosum and also separated the X. interiore central Australian populations from X. sp. Pilbara. Unexpectedly, X. sp. New England separated into two clusters, with one representing the Henry River Falls population clustering close to populations of X. viscosum, and the other Round Waterhole Creek and Jeogla populations clustering near samples of X. sp. Glencoe and X. sp. Mount Merino. Also, X. bracteatum sens. str. forms three groups, comprising (1) introduced plants on St Helena, (2) naturally occurring populations in New South Wales, and (3) the cultivars (Fig. 7, labelled a, b, and c respectively). Tasmanian and South Australian populations of X. bicolor, X. halmaturorum, and X. sp. Lofty form a single cluster in both Axes 1 and 2, and 1 and 3.

Fig. 7.

Principal coordinate analysis of 5637 single-nucleotide polymorphism loci representing species and putative entities of Xerochrysum in the ‘Bracteatum’ group. Each dot represents an individual sample, coloured by population. (a) Axes 1 and 2; (b) Axes 1 and 3.

The smaller subset ‘Boreale’ PCoA Axes 1 and 2 (Fig. 8a) explained 30.4% of the genetic variation of these samples, and clearly separated the Gheebulum Kunungai (Moreton Island) National Park population of X. sp. North Stradbroke Island from all other samples. Other populations of this putative entity formed separate clusters; the Iluka population was nested within X. sp. Northern Tablelands as was the naturalised X. bracteatum sens. lat. from Tasmania; the Noosa NP, Town of 1770 and K’gari (Fraser Island) populations clustered very close to Gloucester Tops plants of X. sp. Northern Tablelands as well as Chinchilla and Narrabri plants of X. bracteatum sens. lat.; and the Byfield plants clustered as a distinct group nearby. Samples of X. sp. North Kennedy clustered with X. sp. Fly Point, X. sp. Walker Point and X. sp. Mount Elliott, except for the single sample from Eungella, west of Mackay, which was placed either intermediate to the Yeppoon plants (Fig. 8a), or the Byfield plants (Fig. 8b). All samples of X. boreale formed a distinct and well-separated cluster. ‘Boreale’ group PCoA Axes 1 and 3 (Fig. 8b) explained 28.5% of the genetic variation and showed distinct separation of X. sp. Fly Point, X. boreale and the Gheebulum Kunungai (Moreton Island) National Park population of X. sp. North Stradbroke Island from all other samples. Clustering of remaining samples from the ‘Boreale’ group PCoA Axes 1 and 3 was in accordance with Axes 1 and 2.

Fig. 8.

‘Boreale’ principal coordinate analysis of 4637 single-nucleotide polymorphism loci representing some species and putative entities of Xerochrysum. Each dot represents an individual sample, coloured by population. (a) Axes 1 and 2; (b) Axes 1 and 3.

PCoA of the X. sp. North Kennedy and closely associated entities, Axes 1 and 2 (Fig. 9a), contained 29.7% of the genetic variation of these samples. Axes 1 and 3 (Fig. 9b) contained 23.7% of the genetic variation. Populations of X. sp. North Kennedy formed three clusters congruent with a north–south distribution. Both Axes 1 and 2, and Axes 1 and 3 showed X. sp. Fly Point and X. sp. Walker Point as separate clusters from X. sp. North Kennedy.

Fig. 9.

Xerochrysum sp. North Kennedy and genetically similar entities principal coordinate analysis of 1342 single-nucleotide polymorphism loci. Each dot represents an individual sample, coloured by population. (a) Axes 1 and 2; (b) Axes 1 and 3.

Population genetic structure Bayesian genetic clustering

For the ‘Bracteatum’ group, the log-likelihood of the model suggested K lay in the range K = 6–9 ( Supplementary Fig. S12 (SB21014_AC.PDF)). There was very little increase in K from K = 6, and, at K = 7, large variations in mean log-likelihood made interpretation uncertain. This indicated that the single-nucleotide polymorphism data may represent between six and nine distinct entities. STRUCTURE bar plots in the range K = 6–9 suggested that there is no shared ancestry or recent gene flow between X. bracteatum sens. str. and all of the putative entities except a small proportion with X. sp. Flinders Range populations, which contained a complex mix of allele frequencies (Fig. 10, S13). Xerochrysum papillosum was distinct from all other entities K = 6–9. The putative entities Xerochrysum sp. Mount Merino and X. sp. Point Lookout were different mixtures of ancestry clusters. Bar plots between K = 6–9 also suggest that X. viscosum and X. sp. Mount Kaputar share a common ancestry, with only slight variations between populations, as do X. sp. Barrington Tops–X. sp. Glencoe, and Xerochrysum interiore–X. sp. Pilbara.

Fig. 10.

STRUCTURE bar plots for ‘Bracteatum’ samples of Xerochrysum, major clustering modes K = 6. Bar plots show each individual as a horizontal bar divided into segments on the basis of the proportion of ancestry suggested for 1–16 subpopulations across 8 of the 16 runs; n = 246. Fine black lines delineate sampling locations.

Common ancestry was also suggested among X. bicolor, X. halmaturorum and X. sp. Lofty Ranges (Fig. 10). At K = 7–8, different allele frequencies were suggested between X. bicolor and X. halmaturorum, with X. sp. Lofty Ranges sharing proportions of both ( Supplementary Fig. S13 and Table S10 (SB21014_AC.PDF)). At K = 9, X. bicolor was again similar to X. sp. Lofty Ranges, with small differences in ancestry in X. halmaturorum.

Bayesian analysis on a subset of the ‘Bracteatum’ data examining allele frequencies shared among X. sp. Barrington Tops, X. sp. Glencoe, X. sp. New England and X. sp. Point Lookout suggested K = 5 ( Supplementary Fig. S14 (SB21014_AC.PDF)). Results confirmed separate ancestry of X. sp. Barrington Tops, X. sp. Glencoe, and X. sp. Point Lookout (Fig. 11), with X. sp. New England diverged into two lineages, with the population at Round Waterhole Creek being largely distinct from those at Henry River Falls and Jeogla.

Fig. 11.

STRUCTURE bar plots for the putative species Xerochrysum sp. Barrington Tops (white, pale yellow and yellow phyllary colours), X. sp. Glencoe, X. sp. New England, and X. sp. Point Lookout, major clustering modes K = 5. Bar plots show each individual as a horizontal bar divided into segments on the basis of the proportion of ancestry suggested for 1–10 subpopulations across all of the 10 runs; n = 52. Fine black lines delineate sampling locations.

A subset containing Xerochrysum bicolor, X. halmaturorum and X. sp. Lofty Ranges suggested K = 3 ( Supplementary Fig. S15 (SB21014_AC.PDF)), with X. bicolor being distinct from both other entities (Fig. 12). This subset suggested greater genetic complexity than did the analysis of ‘Bracteatum’. Populations of X. halmaturorum on Kangaroo Island at Cape St Albans, Lesueur and Pink Bay shared ancestry distinct and separate from plants at Newland Head, which had shared ancestry with the Tothill Range populations. Plants of X. sp. Lofty Ranges at Hindmarsh Falls were suggested to have ~30% ancestry shared with Kangaroo Island populations and the remainder with plants at Newland Head and Tothill Range (Fig. 12).

Fig. 12.

STRUCTURE bar plots for Xerochrysum bicolor, X. halmaturorum, and X. sp. Lofty Ranges major clustering modes K = 3. Bar plots show each individual as a horizontal bar divided into segments on the basis of the proportion of ancestry suggested for 1–10 subpopulations across all of the 10 runs; n = 51. Fine black lines delineate sampling locations.

Bayesian analysis of a subset containing populations of X. viscosum and X. sp. Mount Kaputar was largely congruent with ‘Bracteatum’ data, suggesting X. viscosum and X. sp. Mount Kaputar to be conspecific ( Supplementary Fig. S13, S16, S17 (SB21014_AC.PDF)). Populations at the northern extent of the distribution of X. viscosum, at Torrington, Wallangara and Coomba Falls, were suggested to have different ancestry ( Supplementary Fig. S17 (SB21014_AC.PDF)). The plants at Apsley Falls, previously thought to be a putative new entity conspecific with X. sp. Mount Kaputar, share ~36% ancestry with the Torrington plants.

The log-likelihood of the model of the STRUCTURE analysis for the ‘Boreale’ group ( Supplementary Fig. S18 (SB21014_AC.PDF)), suggested K = 6. However, at K = 7, large variations in mean log probability scores made assessment of K difficult. The main differences between clusters at K = 6 and those at K = 7 ( Supplementary Fig. S19 (SB21014_AC.PDF)) were the suggested divergence of X. bracteatum sens. lat. populations from X. sp. North Stradbroke Island, and the suggested divergence of X. sp. Fly point and X. sp. Walker Point, both from each other, and from X. sp. North Kennedy. These results can also be seen in the major and minor clusters at K = 6 (Fig. 13). Ancestry of all populations of X. boreale, including X. sp. Cox Peninsula, are shared at K = 6 (Fig. 13). Most populations of X. sp. Northern Tablelands shared a common ancestry with the Iluka population of X. sp. North Stradbroke Island. Exceptions were plants in southern Queensland, at The Head and Bunya Mountains NP, which had ~12–23% of X. sp. North Stradbroke Island ancestry. At K = 6, differences between major and minor clusters suggested varying proportions of shared ancestry among X. sp. North Stradbroke Island from Byfield NP, 1770, Noosa National Park and K’gari (Fraser Island) and X. bracteatum sens. lat. from Narrabri and Chinchilla. The Gheebulum Kunungai (Moreton Island) National Park population of X. sp. North Stradbroke Island was distinct from all other samples in the analysis. Bar plots of major and minor clusters at K = 6 showed that all populations sampled of X. sp. North Kennedy clustered with X. sp. Mount Elliott and suggested similar ancestry to populations at Fly Point and Walker Point, except for differing proportions of a maroon-coloured cluster (Fig. 13).

Fig. 13.

STRUCTURE bar plots for ‘Boreale’ samples of Xerochrysum, major and minor clustering modes K = 6. Bar plots show each individual as a horizontal bar divided into segments on the basis of the proportion of ancestry suggested for 1–10 subpopulations across all of the 10 runs; n = 148. Fine black lines delineate sampling locations.

Bayesian analysis of a subset of the ‘Boreale’ data examining allele frequencies shared between X. boreale, X. sp. Fly Point, X. sp. Mount Elliott, X. sp. North Kennedy and X. sp. Walker Point suggested K = 6 ( Supplementary Fig. S20 (SB21014_AC.PDF)). Results confirmed the unique ancestry of both X. sp. Fly Point and X. sp. Walker Point, and suggested population genetic structure between eastern and western populations of X. boreale, and between northern and southern populations of X. sp. North Kennedy, with the southern populations at Paluma and Blackbraes National Park having ancestry similar to that of X. sp. Mount Elliott (Fig. 14). Plants at Wondecla were suggested to have ~56% ancestry shared with Herberton and Baldy Mountain, and ~43% with Blackbraes National Park. The Paluma Range and Mount Elliott populations were suggested to have a complex ancestry; however, examination of the raw output showed both clustering with the Blackbraes population in 8 of the 10 runs at K = 6. A subset analysing allele frequencies shared between X. sp. North Stradbroke Island, X. sp. Northern Tablelands, and X. bracteatum sens. lat. (including X. sp. Chinchilla and X. sp. weedy) suggested K = 4 ( Supplementary Fig. S21 (SB21014_AC.PDF)), and STRUCTURE bar plots ( Supplementary Fig. S22 (SB21014_AC.PDF)) were congruent with ‘Boreale’ results (Fig. 13).

Fig. 14.

STRUCTURE bar plots for Xerochrysum boreale and genetically similar putative species, major and minor clustering modes K = 6. Bar plots show each individual as a horizontal bar divided into segments on the basis of the proportion of ancestry suggested for 1–10 subpopulations across all of the 10 runs; n = 63. Fine black lines delineate sampling locations.

For the analysis of putative relatives of X. sp. Blackfellows Gap, the log-likelihood of the model suggested K = 5 ( Supplementary Fig. S23 (SB21014_AC.PDF)); however, biologically relevant clustering occurred up to K = 6. STRUCTURE bar plots at K = 4 did not distinguish between X. bracteatum sens. str., X. viscosum and X. sp. Blackfellows Gap, but did separate X. subundulatum, X. palustre and X. aff. palustre (Fig. 15). At K = 5, 9 of the 10 runs separated X. bracteatum sens. str. and X. viscosum, whereas X. sp. Blackfellows Gap appeared to share a complex mix of ancestry with both of these species and small proportion of X. subundulatum.

Fig. 15.

STRUCTURE bar plots, for species of Xerochrysum associated with X. sp. Blackfellows Gap (marked with an asterisk, *), for major clustering modes K = 4–5. Bar plots show each individual as a horizontal bar divided into segments on the basis of the proportion of ancestry suggested for four or five ancestral populations across all runs at K = 4 and 9 of the 10 runs at K = 5; n = 114. Fine black lines delineate sampling locations, numbered as in  Supplementary Table S14 (SB21014_AC.PDF). Of the two samples collected from Namadgi National Park (Location 9), morphological characters indicated that one is clearly X. subundulatum, and the other is X. sp. Blackfellows Gap (N.T.Burbidge 6926).

Xerochrysum Tzvelev, Novosti Sist. Vyssh. Rast. 27: 151 (1990)

Type: Xerochrysum bracteatum (Vent.) Tzvelev.

Bracteantha Anderb. & Haegi, Opera Bot. 104: 102 (1991), nom. illeg. Type: Bracteantha bracteata (Vent.) Anderb. & Haegi.

Annual or perennial herbs, usually taprooted, sometimes rhizomatous. Indumentum cobwebby, felted, hirsute, hispid, pilose, tomentose, villous, or woolly, with septate trichomes, often flagelliform, and with sessile or stipitate glands. Leaves alternate; lamina flat or with margin recurved. Capitula terminating branches or branchlets, homogamous or heterogamous, disciform. Phyllaries multiseriate, medial phyllaries longest; lamina rigidly chartaceous, often spreading at junction with claw when mature; claw coriaceous, broadly oblong, flat; stereome broad, that of inner phyllaries fenestrate, veins numerous and extending into lamina, veins each of equal thickness in the X. bracteatum group, or central vein thickest in the X. milliganii group. Receptacle ± flat or concave, epaleate. Outermost florets usually sterile or sometimes female; corolla very narrowly tubular, shorter than bisexual florets, 3-, 4- or 5-lobed. Inner (or all) florets bisexual; corolla narrowly tubular, 5-lobed, lobes ovate, yellow to orange; anthers with apical appendage ovate and outwardly concave, tails slender, ±equal to collar, pollen pale yellow; style arms slender, with rounded, clavate, ovate, deltoid, triangular or narrowly triangular stylar appendage, yellow. Cypsela cylindrical or oblong, ~2.5–3.5 mm long; pericarp thick, finely striated, glabrous, surface with linear idioblasts, brown or straw- or bronze-coloured; stipe hollow, carpopodium of one row of thickened cells; apex patelliform when mature. Testa free from pericarp, cells ±equilateral, without thickening; vein passing to apex. Pappus uniseriate; bristles slender, equal to or exceeding corolla, white or yellow, consistent with the colour of the medial phyllaries, barbellate with apical cells acute and occasionally coloured red, bristles very shortly united at base and eventually deciduous as a whole or in pieces in the X. bracteatum group, or persistent in the X. milliganii group.

Xerochrysum bracteatum group

Xerochrysum banksii (A.Cunn. ex DC.) T.L.Collins & I.Telford, comb. nov.

Helichrysum banksii A.Cunn. ex DC., Prodr. 6: 188 (1838); Gnaphalium banksii (A.Cunn. ex DC.) Sch.Bip., Bot. Zeit. 3: 171 (1845). Type citation: ‘in Novae-Holl. ora boreali-orient. ad flum. Endeavour in sylvaticus graminosis olim legit cl. Banks et postea A Cunningham jul. flor (v.s. comm. a cl. A. Cunn.)’. Type: Grassy forest-land, Endeavour River, N.E. Australia [Queensland], lat. 15° south, July 1819, A. Cunningham s.n. (lecto, here designated: G-DC G00328465*; isolecto: K 000899119*).

[Helichrysum bracteatum auct. non (Vent.) Willd.: G.Bentham, Fl. Austral. 3: 620 (1867), p.p.]

[Xerochrysum bracteatum auct. non (Vent.) Tzvelev: N.N. Tzvelev, Novosti Sist. Vyssh. Rast. 27: 151 (1990), p.p., populations on coastal headlands between Cooktown and Cairns, Queensland only].

Prostrate, tap-rooted, perennial herb. Stems and branches hirsute, scabrid, glabrescent and with glands; internode length 5–60 mm. Flowering stems branched or unbranched. Basal leaf rosette present at flowering in first year, later absent. Basal leaves oblanceolate to spathulate, 50–120 mm long and 10–25 mm wide, base amplexicaul, apex mucronate, margin hirsute; basal leaf abaxial indumentum with glands and occasionally hirsute with septate trichomes, midvein indumentum pilose with septate trichomes; basal leaf adaxial indumentum hirsute with septate trichomes. Cauline leaves oblanceolate, 20–50 mm long and 5–10 mm wide, base subauriculate and amplexicaul, apex mucronate, margin hirsute; abaxial indumentum with glands, midvein indumentum hirsute with septate trichomes; adaxial indumentum hirsute, scabrid and with glands. Foliaceous bracts subtending capitula 6–12 mm long, margin hispid. Capitula 30–40 mm wide, terminal, solitary. Outer phyllaries broad-ovate, brown or straw-coloured, basal margin fimbriate and hispid, abaxial surface smooth, apex apiculate. Medial phyllaries narrow ovate to lanceolate, abaxially yellow, apex cuspidate. Stylar appendages triangular. Cypsela oblong, ~2.5 mm long and 0.9 mm wide, cross-section squarish or circular; pericarp straw- or brass-coloured, idioblasts present. Pappus deciduous, ~6 mm long.

Selected specimens examined

QUEENSLAND: Cook: Endeavour River, June 1770, J. Banks & D. Solander s.n. (MEL 1591810!); Cooktown, 1877, W. Persieh s.n. (MEL 0061318A!); Endeavour River, 1882, W. Persieh s.n. (MEL 0061336A!); Annan River National Park, Walker Point, 22 Oct. 2018, A.J. Saunders 1 (BRI!, CANB!, CNS!, NE 110024!); Walker Point, S of Cooktown, 5 Dec. 2005, B.S. Wannan 4156 (BRI!, BSW, NSW!); Mossman’s [=Mossman] River, 1886, W.A. Sayer s.n. (MEL 0061192A!); Trinity Bay, 1881, G. Karsten s.n. (MEL 0061211A!); Trinity Bay, E. Fitzalan s.n. (MEL 0061314A!).

Fig. 16.

Distribution of Xerochrysum banksii.

Fig. 17.

Lectotype of Xerochrysum banksii (G-DC G00328465). Image: © Conservatoire et Jardin botaniques de la Ville de Genève.

Xerochrysum berarngutta T.L.Collins & I.Telford, sp. nov.

Type: AUSTRALIA: New South Wales: Northern Tablelands: New England National Park, Eagles Nest Lookout, below Point Lookout, 5 Feb. 2005, I.R. Telford 12830 & L.M. Copeland, (holo: NSW!; iso: BRI!, MEL!, NE 83736!, PERTH!).

Xerochrysum sp. Point Lookout (I.R.Telford 12830) NE Herbarium, CHAH, Austral. Pl. Census (2020) [accessed 20 February 2020].

[Xerochrysum bracteatum auct. non (Vent.) Tzvelev: N.N. Tzvelev, Novosti Sist. Vyssh. Rast. 27: 151 (1990), p.p., populations on the high escarpment cliffs at Point Lookout, New England National Park, New South Wales only].

Selected specimens examined

NEW SOUTH WALES: Northern Tablelands: New England National Park, Point Lookout, 12 Apr. 2017, T.L. Collins 958 & J.J. Bruhl (BRI!, NE!, NSW!); New England National Park, Eagles Nest Lookout, 11 Mar. 2006, G.P. Duley 69, J.J. Bruhl & I.R. Telford (NE!).

Fig. 18.

Distribution of Xerochrysum berarngutta.

Fig. 19.

Isotype of Xerochrysum berarngutta (I.R.Telford 12830 & L.M.Copeland, NE 83736).

Xerochrysum bicolor (Lindl.) R.J.Bayer, Kew Bulletin 56: 1014 (2001)

Helichrysum bicolor Lindl., Bot. Reg. 21: t. 1814 (1835); Gnaphalium bicolor (Lindl.) Sch.Bip. Bot. Zeit. 3: 171 (1845); Helichrysum bracteatum var. bicolor (Lindl.) L.H.Bailey, Cycl. Amer. Hort. 2: 723 (1900); Bracteantha bicolor (Lindl.) Anderb. & Haegi, Op. Bot. 104: 105 (1991). Type citation: ‘introduced by Mr. Low of the Clapton Nursery… It is a native of Van Diemen’s Land, whence our excellent correspondent Mr. Gunn has sent beautiful specimens (No. 111).’ Type: in insula van Dieman (Herb. Gunniani No. 111), s. dat., R.C. Gunn 111, (lecto: CGE; isolecto: MEL 61303!; possible isolecto: NSW 122366, fide P. G. Wilson, Nuytsia 28: 14 (2017)).

Xerochrysum halmaturorum Paul G.Wilson, Nuytsia 28: 15 (2017). Type: Cape St Albans, Kangaroo Island, South Australia, 24 Nov. 1994, B.M. Overton 2513 (holo: AD 99610190!; iso: MEL 2048046!).

Erect, perennial, taprooted herb. Stems and branches with glands, and scabrid or hispid (prominent raised ridges along stems), internode length 10–35 mm. Basal leaf rosette absent at flowering. Basal leaves obovate or spathulate, 50–150 mm long and 10–30 mm wide, base auriculate or attenuate and amplexicaul, margin hirsute, pilose or hispid with septate trichomes, apex obtuse to apiculate and mucronate; abaxial indumentum with glands, midvein indumentum hirsute to hispid with septate trichomes and with glands; adaxial indumentum scabrid or hispid with septate trichomes, and with glands. Cauline leaves obovate, 40–120 mm long and 10–35 mm wide, base auriculate and amplexicaul, margin hispid or scabrid with dense, shorter septate trichomes as well as scattered septate trichomes, 2–4 times longer, and with stipitate glands; apex acuminate to apiculate and mucronate; abaxial indumentum with glands, midvein indumentum hispid and scabrid with septate trichomes; adaxial indumentum hispid or scabrid with septate trichomes, and with glands. Foliaceous bracts subtending capitula 5–15 mm long, margin hispid with stipitate glands. Capitula 30–60 mm wide, terminal, in panicles. Outer phyllaries broad-ovate, brown or straw-coloured, basal margin fimbriate or hispid, abaxial surface smooth, apex acuminate. Medial phyllaries narrow ovate to lanceolate, abaxially brown, white or yellow, apex acuminate to cuspidate. Stylar appendages deltoid to ovate. Cypsela oblong, ~2.5 mm long and 0.75 mm wide, cross-section squarish; pericarp brown, idioblasts present. Pappus deciduous ~4–8 mm long.

Selected specimens examined

SOUTH AUSTRALIA: Goyder: Tothill Range, Mollers Gap Road, 26 Nov. 2017, T.L. Collins 988 & A.N. Schmidt-Lebuhn (AD!, CANB!, NE!). Adelaide Hills: South Australia, 10 Nov. 1879, R. Tate s.n. (AD!). Victor Harbor: South Australia, 1 Dec. 1909, E.H. Ising s.n. (AD!); Hindmarsh Falls, 23 Nov. 2017, T.L. Collins 982 & A.N. Schmidt-Lebuhn (AD!, CANB!, NE!); Newland Head Conservation Park, 23 Nov. 2017, T.L. Collins 981 & A.N. Schmidt-Lebuhn (AD!, CANB!, NE!). Yankalilla: South Australia, Jan. 1926, J.B. Cleland s.n. (AD!). Kangaroo Island: Cape St Albans, 20 Nov. 2017, T.L. Collins 973 & A.N. Schmidt-Lebuhn (AD!, CANB!, NE!). VICTORIA: Southern Grampians: Victorian Midlands, 29 Dec. 1988, R.M. King 9703 & F.E. Heinz (MEL!). Horsham: Victorian Midlands, 8 Nov. 1987, S.T.W. Parfett 134 (MEL!). TASMANIA: Little Badger Island, s. dat., J.S. Whinray 8605 (CANB, HO, MEL!); Alum Cliffs, S of Taroona, Hobart, 28 Feb. 2018, T.L. Collins 1016 & R.L. Andrew (NE!, HO!, CANB!); Arthur Pieman Conservation Reserve, 4 Mar. 2018, T.L. Collins 1033 & R.L. Andrew (NE!, HO!, CANB!); S of Temma on coastal track, 4 Mar. 2018, T.L. Collins 1034 & R.L. Andrew (NE!, HO!, CANB!).

Fig. 20.

Distribution of Xerochrysum bicolor.

Xerochrysum boreale Paul G.Wilson, Nuytsia 28: 17 (2017)

Type: Port Keats opposite Dorcherty Island, Northern Territory, 9 Aug. 1983, C.R. Dunlop 6459 & G. Wightman (holo: DNA D0021944!; iso: AD 98419226, BRI, CANB 345434*, MEL 0291510, NSW 518497!).

Xerochrysum bracteatum subsp. (Port Keats C. Dunlop + 6459), A. E. Holland in P. D. Bostock and A. E. Holland (eds), Census Queensl. Fl. 32 (2007).

Xerochrysum bracteatum subsp. Port Keats (C. Dunlop + 6459) Qld Herbarium, CHAH, Austral. Pl. Census (2020) [accessed 20 February 2020].

Erect, annual or perennial, taprooted herb. Stems and branches cobwebby or pilose, internode length 5–30 mm. Basal leaf rosette present in first year at flowering, later absent. Basal leaves oblanceolate to obovate, 30–70 mm long and 5–12 mm wide, base amplexicaul, margin cobwebby or pilose with septate trichomes, apex mucronate; abaxial indumentum hirsute with septate trichomes and with glands, midvein indumentum cobwebby or hirsute with septate trichomes; adaxial indumentum hirsute with septate trichomes. Cauline leaves oblanceolate, 20–80 mm long and 4–9 mm wide, base amplexicaul, margin cobwebby or hirsute with septate trichomes, apex mucronate; abaxial indumentum hirsute with septate trichomes, and with glands, midvein indumentum cobwebby to hirsute; adaxial indumentum cobwebby to hirsute with septate trichomes. Foliaceous bracts subtending capitula 5–8 mm long, margin cobwebby. Capitula 25–35 mm wide, terminal, in panicles. Outer phyllaries broad-ovate, brown or straw-coloured, basal margin hispid, abaxial surface smooth, apex apiculate. Medial phyllaries ovate to narrow ovate, abaxially yellow, apex cuspidate. Stylar appendages narrowly triangular. Cypsela oblong, ~2.3 mm long and 0.75 mm wide, cross-section circular; pericarp grey–brown, idioblasts present. Pappus deciduous, ~6–7 mm long.

Selected specimens examined

NORTHERN TERRITORY: Darwin and Gulf: Dundee Beach, S of Dunheved Road, 2 Oct. 2018, T.L. Collins 1088 & J.J. Bruhl (CANB!, DNA!, NE!); Dhupuwamirri Road, on road to Mirrnatja, 9 Oct. 2018, T.L. Collins 1091 & J.J. Bruhl (CANB!, DNA!, NE!); Mirrnatja, ~2.2 km N of village, 10 Oct. 2018, T.L. Collins 1092 & J.J. Bruhl (CANB!, DNA!, NE!); Central Arnhem Road, Yunupingu Cattle Farm, 10 Oct. 2018, T.L. Collins 1093 & J.J. Bruhl (CANB!, DNA!, NE!); Wadeye, Old Mission Road, 5 Oct. 2018, T.L. Collins 1089 & J.J. Bruhl (CANB!, DNA!, NE!); Wadeye, on unnamed coast track, 5 Oct. 2018, T.L. Collins 1090 & J.J. Bruhl (CANB!, DNA!, NE!). WESTERN AUSTRALIA: West Kimberley: West Kimberley, 1901, F.M. House s.n. (PERTH!). Wyndham–East Kimberley: Head of King Edward River, 7 Sep. 1921, C.A. Gardner 1565 (PERTH!).

Fig. 21.

Distribution of Xerochrysum boreale.

Xerochrysum bracteatum (Vent.) Tzvelev, Novosti Sist. Vyssh. Rast. 27: 151 (1990)

Xeranthemum bracteatum Vent., Jard. Malmaison 1: 2, t. 2 (1803); Helichrysum bracteatum (Vent.) Andrews, Bot. Repos. 6: ad t. 428 (1805); Helichrysum chrysanthum Pers., Syn. Plant. 2(2): 414 (1807), nom. illeg., nom. superfl.; Helichrysum bracteatum (Vent.) Willd., Enum. Pl. 2: 869 (1809), isonym; Xeranthemum lucidum Maund, Bot. Gard. 2: 135 (1828), nom. illeg., nom. superfl.; Helichrysum bracteatum (Vent.) Andrews var. bracteatum, A.P. de Candolle, Prodr. 6: 189 (1838); Gnaphalium chrysanthum Sch.Bip., Bot. Zeitung 3: 171 (1845); Bracteantha bracteata (Vent.) Anderb. & Haegi, Op. Bot. 104: 102 (1991). Type citation: ‘originaire de la Nouvelle Hollande’ [Port Jackson, Australia]. Type: ex H. Malmaison, s. dat., E.-P.Ventenat s.n. (holo: G-DC G00341478*).

Helichrysum bracteatum var. chrysanthum DC., A.P. de Candolle, Prodr. 6: 189 (1838), nom. inval.

Argyrocome bracteata B.D.Jacks., Index Kew. 1(1): 184 (1893) nom. inval., pro syn.

Helichrysum lucidum var. normalis F.Muell., Fragm. 11(89): 48 (1878) nom. inval.

Erect, annual or sometimes short-lived perennial (dependant on season), tap-rooted herb, 0.5–1.8 m tall. Stems and branches cobwebby, hirsute to pilose with septate trichomes, or glabrescent, and with glands; internode length 10–35 mm. Flowering stems branched, or unbranched (becoming branched with maturity, occasionally single-stemmed). Basal leaf rosette usually absent at flowering. Basal leaves elliptic to spathulate, 50–150 mm long, and 10–30 mm wide, base amplexicaul and attenuate, margin woolly to hirsute with septate trichomes, apex obtuse to apiculate; abaxial indumentum hispidulous with septate trichomes, and with glands; adaxial indumentum hispidulous with septate trichomes. Cauline leaves oblanceolate, 50–180 mm long, 5–25 mm wide, base attenuate and subamplexicaul, margin hispid with septate trichomes, apex acuminate to acute; abaxial indumentum with glands, midvein indumentum hispid with septate trichomes; adaxial indumentum hispidulous with septate trichomes and with glands. Foliaceous bracts subtending capitula ~8–10 mm long, margin hispid with septate trichomes. Capitula terminal, 30–50 mm wide, in panicles; outer phyllaries broad-ovate, yellow or brown, basal margin hispid, abaxial surface smooth, apex apiculate. Medial phyllaries oblong, narrow ovate or lanceolate, abaxially brown or yellow, apex cuspidate. Stylar appendages deltoid to acute. Cypsela oblong, ~2.2 mm long and 0.75 mm wide, cross-section squarish; pericarp grey–brown, idioblasts present. Pappus deciduous 5–6 mm long.

Selected specimens examined

NEW SOUTH WALES: Central Tablelands: Mount Tomah, Lithgow Road, 25 Jan. 1959, B.R. Paterson s.n. (CANB*). Central Coast: The Oaks, on road to Penrith (Silverdale Road), 15 Dec. 2018, T.L. Collins 1005 (CANB!, NE!, NSW!); Hopetoun Park, Panorama House Motel, Bulli Lookout, 7 Jan. 2019, T.L. Collins 1168 (CANB!, NE!, NSW!); Mount Keira Road, 7 Jan. 2019, T.L. Collins 1169 (CANB!, NE!, NSW!). South Coast: Nowra Road ~4 km E of intersection with Gretas Road, 26 Jan. 2019, T.L. Collins 1174 (CANB!, NE!, NSW!); Central Tilba, Paradise Hill, 27 Jan. 2019, T.L. Collins 1175 (CANB!, NE!, NSW!); Gulaga National Park, Mount Dromedary Trail, 27 Jan. 2019, T.L. Collins 1177 (CANB!, NE!, NSW!); Nullica State Forest, track to Nethercote Falls, 3 Feb. 2019, T.L. Collins 1181 (CANB!, NE!, NSW!). VICTORIA: East Gippsland: on track to summit of Mount Ellery, 22 Feb. 1984, D.E. Albrecht 212 (AD, MEL!); Mount Elizabeth Nature Conservation Reserve, 26 Oct. 2019, J.J. Bruhl 3643, S. Dema, & H.T. Kennedy (CANB!, MEL!, NE 109790!, NSW!).

Fig. 22.

Distribution of Xerochrysum bracteatum.

Xerochrysum copelandii J.J.Bruhl & I.Telford, sp. nov.

Type: AUSTRALIA: New South Wales: Northern Tablelands: Styx River, 50 m NW of bridge SW of Jeogla on road to Kempsey, 1 Apr. 2007, J.J. Bruhl 2649 & O.D.Q. Bruhl (holo: NSW!; iso: BRI!, CANB!, K!, MEL!, MO!, NE 90257!).

Xerochrysum sp. New England (L.M.Copeland 3731) NE Herbarium, CHAH, Austral. Pl. Census (2020) [accessed 20 February 2020].

[Xerochrysum bracteatum auct. non (Vent.) Tzvelev: N.N. Tzvelev, Novosti Sist. Vyssh. Rast. 27: 151 (1990), p.p., populations in gorge-rim habitat in the New England Tablelands Bioregion only, but excluding the population at Henry River Falls thought to be a hybrid with X. viscosum].

Selected specimens examined

NEW SOUTH WALES: Northern Tablelands: Guy Fawkes River National Park, Henry River Falls, 24 Aug. 2017, T.L. Collins 969, R.L. Andrew, J.J. Bruhl & J.K. Janes (NE!); Round Waterhole Creek, 11 Feb 2018, T.L. Collins 1013 & B. Wright (CANB!, BRI!, NE!, NSW!); Hillgrove Gorge, 28 Feb. 1999, J.J. Bruhl 1840 & I.R. Telford (NE!); Washpool National Park, S of summit of Mount Bajimba, 25 Feb. 2011, L.M. Copeland 4502 (BRI, NE!, NSW); Great Dividing Range, Washpool National Park, 25 Jan. 2014, I.R. Telford 13440 & T. Vollbon (NE!).

Fig. 23.

Distribution of Xerochrysum copelandii.

Fig. 24.

Isotype of Xerochrysum copelandii (J.J.Bruhl 2649 & O.D.Q.Bruhl, NE 90257).

Xerochrysum frutescens J.J.Bruhl & I.Telford, sp. nov.

Type: AUSTRALIA: Queensland: Moreton: Main Range, Mount Cordeaux, summit ridge, 1 Nov. 2005, I.R. Telford 12874, J.J. Bruhl & L.M. Copeland (holo: BRI!; iso: NE 85983!, CANB!, K!, NSW!).

Helichrysum sp. 1 (McPherson Range), J.D. Briggs and J.H. Leigh, Rare or Threatened Austral. Pl. 24 (1988).

Helichrysum sp. (Mt Merino S.T.Blake 21554), A.E. Holland in R.J.F. Henderson (ed.), Queensl. Vasc. Pl.: Names and Distrib. 39 (1994).

Xerochrysum bracteatum subsp. Mount Merino (S.T.Blake 22869) Qld Herbarium, A.E. Holland in P.D. Bostock and A.E. Holland (eds), Census Queensl. Fl. 32 (2007).

Xerochrysum sp. Mount Merino (S.T.Blake 22869) NE Herbarium, CHAH, Austral. Pl. Census (2020) [accessed 20 February 2020].

Xerochrysum ‘Dargan Hill Monarch’, Australian Cultivar Registration Authority 1977.

[Xerochrysum bracteatum auct. non (Vent.) Tzvelev: N.N. Tzvelev, Novosti Sist. Vyssh. Rast. 27: 151 (1990), p.p., only populations in the Main, McPherson and Tweed Ranges, Queensland and New South Wales].

Selected specimens examined

QUEENSLAND: Moreton: Main Range National Park, ~200 m S of summit of Mount Cordeaux, 11 Mar. 2005, L.M. Copeland 3904 & A.J. Lynch (NE!, PERTH); Main Range National Park, Goomburra Section, 28 Oct. 2015, P.I. Forster 43151 (BRI!); Mount Mitchell, Cunninghams Gap, 18 Aug. 1992, P.I. Forster 11105 (BRI!); Mount Lindesay, base of trachyte cliffline, 15 Nov. 1990, P.I. Forster 7562 (BRI!). NEW SOUTH WALES: North Coast: McPherson Range, Limpinwood Nature Reserve, Mount Merino, 6 Nov. 2005, I.R. Telford 12886 (NE!); Koreelah National Park, 28 Mar. 2009, L.M. Copeland 4353 (CANB, NE!, NSW); Lamington Plateau, Hunter’s Lookout, 12 Mar. 2014, P.I. Forster 40802 (BRI!).

Fig. 25.

Distribution of Xerochrysum frutescens.

Fig. 26.

Isotype of Xerochrysum frutescens (I.R.Telford 12874, J.J.Bruhl & L.M.Copeland NE 85983).

Xerochrysum gudang T.L.Collins & J.J.Bruhl, sp. nov.

Type: AUSTRALIA: Queensland: Cook: Somerset Lookout, Fly Point, ~350 m SW of lookout parking area, 50 m from rocky coast, 28 June 2018, T.L. Collins 1061 & J.J. Bruhl, (holo: BRI!; iso: CANB!, CNS!, NE 107429!).

[Xerochrysum bracteatum auct. non (Vent.) Tzvelev: N.N. Tzvelev, Novosti Sist. Vyssh. Rast. 27: 151 (1990), p.p., populations in the Torres Strait and on the northern tip of Cape York Peninsula, Queensland only].

Selected specimens examined

QUEENSLAND: Cook: Albany Island, s.dat., W. Hill 71 (K000899118*); Fly Point, near Albany Pass, Cape York Peninsula, 25 June 1973, S. Powell 9 (CANB!); Fly Point, ~11 km SE of Cape York, 30 Oct. 1965, L.S. Smith 12636 (BRI!); Newcastle Bay, Cape York Peninsula, 15 Feb. 1986, D.L. Jones s.n. (BRI!); Newcastle Bay, 2.5 miles S of Somerset, 2 May 1948, L.J. Brass 18778 (A, CANB!); Headland above Nanthau Beach, 4.5 km direct line SSW of Somerset, 30 June 1985, K.R. Thiele 905 (CANB!).

Fig. 27.

Distribution of Xerochrysum gudang.

Fig. 28.

Isotype of Xerochrysum gudang (T.L.Collins 1061 & J.J.Bruhl, NE 107429).

Xerochrysum hispidum T.L.Collins & I.Telford, sp. nov.

Type: AUSTRALIA: New South Wales: South Western Plains: Mid Western Highway, 21 km from Rankins Springs towards West Wyalong, 12 Oct. 2019, I.R. Telford 13546, J.J. Bruhl & S. Dema, (holo: NSW!; iso: BRI!, CANB!, MEL!, NE 109359!, US!).

[Xerochrysum bracteatum auct. non (Vent.) Tzvelev: N.N. Tzvelev, Novosti Sist. Vyssh. Rast. 27: 151 (1990), p.p. populations in south-western New South Wales, inland South Australia and inland Victoria with prominent, robust, hispid septate trichomes scattered on the leaf lamina adaxial surface, leaf margin and abaxial midvein only].

Selected specimens examined

SOUTH AUSTRALIA: unincorporated: Balcanoona, near Nudlamutana Well, 26 Oct. 1967, H. Eichler 19646 (AD!). Elliston: Hambidge Flora and Fauna Reserve, 18 Sep. 1966, C.R. Alcock 1023 (AD!). Cleve: Hincks National Park, summit of Verran Hill, 6 Oct. 1968, J.R. Wheeler 733 (AD!). NEW SOUTH WALES: unincorporated: Scotia Sanctuary, 22 May 2011, D. Wood 240 (CANB!). Lachlan: 2.5 miles [~4 km] E from Euabalong turn-off from Lake Cargelligo, 23 May 1969, P.N. Martensz 178 (CANB*). Cobar: 10.5 miles [~16.8 km] S of Cobar on Nymagee road, 30 Sep. 1966, C.W.E. Moore 4487 (CANB*). Coolamon: Near Ariah Park, ~40 km WNW of Temora, 28 Oct. 1978, C.J. Shepherd 870 (CANB*). VICTORIA: Mildura: Murray-Sunset National Park, 10 Oct. 2014, V. Stajsic 7611 (MEL!); Hattah Lakes National Park, 1 Oct. 1948, A.C. Beauglehole 1101 (MEL!); ~10.5 miles [~16.8 km] NW of Warooka, 25 Oct. 1967, T. Smith 774 (AD!).

Fig. 29.

Distribution of Xerochrysum hispidum.

Fig. 30.

Isotype of Xerochrysum hispidum (I.R.Telford 13546, J.J.Bruhl & S.Dema, NE 109359).

Xerochrysum interiore Paul G.Wilson, Nuytsia 28: 19 (2017)

Type: 4 miles [~6.4 km] east of Acacia Well, Undoolya, Northern Territory, 9 Nov. 1954, G. Chippendale 450 (holo: AD 95805047; iso: BRI, CANB 37993, DNA A0000450, NSW 518728, PERTH 00423815*).

Erect, annual (never biennial), taprooted herb. Stems and branches hispid with septate trichomes, or glabrescent, and with glands; internode length 15–20 mm. Basal leaf rosette often present at flowering, or absent (will flower with loose basal rosette in drier seasons). Basal leaves obovate to spathulate, 70–110 mm long and 15–35 mm wide, base auriculate and attenuate, apex apiculate; abaxial indumentum with glands, midvein indumentum pilose with septate trichomes; adaxial indumentum with scattered septate trichomes. Cauline leaves spathulate to obovate, 50–200 mm long and 10–30 mm wide, leaf base attenuate and auriculate, margin hirsute with septate trichomes, apex mucronate; abaxial indumentum with glands, midvein indumentum hispid with septate trichomes, and with glands; adaxial indumentum hirsute with septate trichomes, and with glands. Foliaceous bracts subtending capitula ~2–4 mm long or absent, margin fimbriate or hispid. Capitula 25–40 mm wide, terminal, in panicles. Outer phyllaries broad-ovate, straw-coloured, basal margin fimbriate, abaxial surface smooth, apex obtuse or apiculate. Medial phyllaries ovate to narrow ovate, abaxially yellow, apex cuspidate. Stylar appendages narrowly triangular or rounded. Cypsela ~3.5 mm long and 0.9 mm wide, cross-section squarish or circular; pericarp grey–brown, idioblasts present. Pappus deciduous, ~10–11 mm long.

Selected specimens examined

NORTHERN TERRITORY: MacDonnell: 1.4 km N of Erldunda Roadhouse, ~50 m E of Stuart Highway, 25 Sep. 2016, J.J. Bruhl 3446 (NE!, NT!); Alice Springs, 500 m NE of the end of Baldissera Drive, 19 Oct. 2014, T.L. Collins 713 (NT!, NE!); S of Alice Springs, 17 km along Maryvale Road, 2 Jul. 2014, T.L. Collins 706 (NT!, NE!). SOUTH AUSTRALIA: unincorporated: De Rose Hill Station ~9 km NE of Homestead, 31 Aug. 1989, H.P. Vonow 1288 (AD!). WESTERN AUSTRALIA: Fortescue: Wanna Munna Road, Pilbara, 22 Aug. 2018, T.L. Collins 1073 & J.J. Bruhl (CANB!, NE!, NT!, PERTH!). Ngaanyatjarraku: ~49 km N of Mount Fanny on Giles–Mount Davies road, 11 May 1977, M. Lazarides 8341 (CANB, NSW, PERTH!). Dundas: 87.7 km E of Norseman on Eyre Highway, 16 Aug. 1995, R.J. Cranfield 10058 (PERTH!).

Fig. 31.

Distribution of Xerochrysum interiore.

Xerochrysum macranthum (Benth.) Paul G.Wilson, Taxon 64(1): 105 (2015)

Helichrysum macranthum Benth. in S.L. Endlicher et al., Enum. Pl. 65 (1837); Gnaphalium macranthum (Benth.) Sch.Bip., Bot. Zeit. 3: 171 (1845); Aphelexis macrantha (Benth.) Hereman Paxton’s Bot. Dict. 41 (1868). Type citation: ‘Swan River (Hügel).’ Type: Freemant. [Freemantle, Western Australia], s. dat., K.A. Huegel s.n. (holo: W 0047162*).

Helichrysum bracteatum var. albidum DC., A.P. de Candolle, Prodr. 6: 189 (1838). Type citation: ‘Rarius in hortis colitur.’ Type: Hort. Genev., 15 Oct. 1834, leg. ign. s.n. (syn: G-DC G 00470178; G-DC G 00470552, n.v., fide P. G. Wilson, Nuytsia 28: 23 (2017)).

Helichrysum glabratum DC., A.P. de Candolle, Prodr. 6: 189 (1838); Gnaphalium glabratum (DC.) Sch.Bip., Bot. Zeit. 3: 171 (1845). Type citation: ‘in Nova Hollandia merid. et orientali.’ Type: Nouvelle Hollande, cȏte oriente, s. dat., leg. ign., s.n. (syn: G-DC G00470680*); Nouvelle Hollande, cȏte merid., s. dat., leg. ign., s.n. (syn: G-DC G00470565*).

Helichrysum robustum Paxton, Paxton’s Mag. Bot. 7: 188 (1840). Type citation: ‘Among the plants raised from the Swan River seeds… It has been raised both in the Clapton and Epsom nurseries.’ Type: n.v., fide P.G. Wilson, Nuytsia 28: 23 (2017).

Helichrysum niveum Graham, Bot. Mag. 67: t. 3857 (1841), nom. illeg., non (L.) Less. (1832); Helichrysum nervosum Don, Hort. Cantab. 13th edn, 567 (1845), nom. nov. Type citation: ‘raised by Mr. Low of Clapton, from seed sent from Swan River by Mr. Drummond, late of Cork, and seedlings, sent to the garden of the Caledonian Horticultural Society in October, 1839.’ Type: Gard. of Caledon. Hort Soc, 1840, leg. ign. (syn: FI 006313*); Hort. Rollison, 1838, Botanist T (syn: K 000899127*).

Erect, taprooted, annual to short-lived perennial herb up to ~70 cm. Stems and branches cobwebby to hirsute and hispid with septate trichomes, or glabrescent, and with glands; internode length 20–40 mm. Basal leaf rosette usually absent at flowering. Basal leaves spathulate, 70–150 mm long and 15–25 mm wide, base amplexicaul, margin cobwebby to hirsute with septate trichomes, apex apiculate; abaxial indumentum with glands, midvein indumentum pilose with septate trichomes and with glands; adaxial indumentum with scattered septate trichomes. Cauline leaves oblanceolate to elliptic, 30–100 mm long and 5–12 mm wide, base subauriculate and amplexicaul, margin hispid with septate trichomes, apex acute; abaxial indumentum with glands, midvein indumentum hirsute with septate trichomes and with glands; adaxial indumentum hispid with septate trichomes, and with glands. Foliaceous bracts subtending capitula 5–7 mm long, margin hispid. Capitula 30–50 mm wide, terminal, in panicles. Outer phyllaries broad-ovate, straw-coloured, pink, white, or occasionally yellow or brown; basal margin fimbriate and hispid, abaxial surface smooth, apex apiculate. Medial phyllaries narrow ovate to lanceolate, abaxially white or yellow, apex cuspidate. Stylar appendages deltoid. Cypsela oblong, ~2.6 mm long and 0.8 mm wide, cross-section squarish; pericarp brown, idioblasts present. Pappus deciduous, ~7–8 mm long.

Selected specimens examined

WESTERN AUSTRALIA: Coorow: north heading track 7.0 km E of intersection of Coastal Road [Indian Ocean Drive] and Eneabba–Coolimba road, 20 Sep. 1994, E.D. Kabay 655 (PERTH!). Chittering: Wannamal (127 km N of Perth), 13 Dec. 2018, T.L. Collins 1148 (CANB!, K!, NE!, PERTH!). Mundaring: Government Road (Chidlow Road), ~1.9 km S of Wooroloo, 13 Dec. 2018, T.L. Collins 1150 (CANB!, NE!, PERTH!, US!); junction Turkey Farm track and York–Chidlow road, 2 Nov. 1996, B.J. Lepschi 3164 & T.R. Lally (AD, CANB, MEL, PERTH!); Wandoo National Park, Talbot West Road, 13 Dec. 2018, T.L. Collins 1153 (CANB!, NE!, PERTH!). Kalamunda: Kalamunda National Park, 1 Nov. 2000, K. Macey 258 (PERTH!); Lesmurdie Falls National Park, 14 Sep. 1992, S. Patrick 1213 (PERTH!). West Arthur: ~23.5 km E of Collie, 19 Dec. 2018, T.L. Collins 1164 (CANB!, NE!, NSW!, PERTH!). Boyup Brook: Donnybrook–Boyup Brook road and intersection with Camballan Road, 19 Dec. 2018, T.L. Collins 1163 (CANB!, MO!, NE!, PERTH!).

Fig. 32.

Distribution of Xerochrysum macranthum.

Xerochrysum macsweeneyorum T.L.Collins, sp. nov.

Type: AUSTRALIA: New South Wales: Northern Tablelands: Roadside reserve, Old Gostwyck Road, ~180 m S of intersection with Bellandean Road, 11 Apr. 2017, T.L. Collins 957 & J.J. Bruhl, (holo: NSW!; iso: BRI!, CANB!, NE 104743!, K!).

[Xerochrysum bracteatum auct. non (Vent.) Tzvelev: N.N. Tzvelev, Novosti Sist. Vyssh. Rast. 27: 151 (1990), p.p., populations of annual or occasionally biennial plants with very small septate flagelliform trichomes on leaf abaxial surface naturally occurring on the Northern Tablelands, New South Wales, and in southern Queensland only].

Selected specimens examined

QUEENSLAND: Darling Downs: Bunya Mountains National Park, track to Barker Creek Lookout from Paradise, 21 Nov. 2018, T.L. Collins 1141 (BRI!, CANB!, NE!); Spring Creek Road, W of Condamine River, 20 Mar. 2018, T.L. Collins 1039 & B. Wright (BRI!, CANB!, NE!); Eukey, Anderson Lane, 21 Nov. 2018, I.R. Telford 13531 (BRI!, CANB!, NE!, NSW!); Stanthorpe, 5 Nov. 1963, W.T. Jones s.n. (CANB 266087.1*). NEW SOUTH WALES: Northern Tablelands: E of Glencoe, Costello Road, 8 Dec. 2018, T.L. Collins 1147 (CANB!, NE!, NSW!); Ben Lomond Range, N of Guyra, 24 Feb. 1970, I.R. Telford 1415 (CANB*); ~20 miles [~32 km] from Guyra towards Glen Innes on New England Highway, 23 Feb. 1961, M.E. Phillips s.n. (CANB 14159.1*, NSW 518529!); junction to New England National Park, 4 Feb. 1996, M. Ito 96011, T. Nishino & Y. Kita (AD, CANB*, NSW, TI); Waterfall Way, ~1.5 km E of Ebor, 22 Apr. 2018, T.L. Collins 1049 & D.T. Collins (AD!, CANB!, NE!, NSW!); near Meldrum between Dorrigo and Ebor, 16 May 1978, B. Barnsley 191 (CANB*); Oxley Wild Rivers National Park, Apsley Falls, 17 Feb. 2018, T.L. Collins 1015 (BRI!, CANB!, HO!, NE!, NSW!); Thunderbolts Way, ~4.96 km S of Nowendoc Road intersection, 22 Dec. 2017, T.L. Collins 1009 & P.L. Collins (BRI!, CANB!, E!, NE!, NSW!); Barrington Tops National Park, Gloucester Tops, 9 Apr. 2018, T.L. Collins 1042 (CANB!, MO!, NE!, NSW!, PERTH!). TASMANIA: Mount Jukes Road, 4.9 km from King River crossing, 20 Feb. 2005, M.L. Baker 1539 (CANB!, HO!, PERTH!); Mount Jukes Road, 21.4 km SSE of Queenstown, 23 Jan. 2018, J.R. Nevin 154 (NE!); Queenstown area, Mount Jukes Road, 4.85 km after the King River bridge, 1 Mar. 2018, T.L. Collins 1023 & R.L. Andrew (CANB!, HO!, NE!).

Fig. 33.

Distribution of Xerochrysum macsweeneyorum.

Fig. 34.

Isotype of Xerochrysum macsweeneyorum (T.L.Collins 957 & J.J.Bruhl, NE 104743).

Xerochrysum murapan T.L.Collins & I.Telford, sp. nov.

Type: AUSTRALIA: New South Wales: Northern Tablelands: Barrington Trail 0.6 km S of the Barrington Tops Forest Road, Barrington Tops State Conservation Area, 27 Feb. 2009, J. R. Hosking 3201 (holo: NSW!; iso: CANB, MEL, NE 95474!, PERTH).

Xerochrysum bracteatum subsp. barringtonense MS, G.J. Harden, New South Wales Fl. Online (see  http://plantnet.rbgsyd.nsw.gov.au/floraonline.htm, accessed 21 May 2018).

[Xerochrysum bracteatum auct. non (Vent.) Tzvelev: N.N. Tzvelev, Novosti Sist. Vyssh. Rast. 27: 151 (1990), p.p., populations of perennial, shortly rhizomatous plants with branching habit restricted to Barrington Tops National Park, New South Wales only].

Selected specimens examined

NEW SOUTH WALES: Northern Tablelands: Moonan State Park [Barrington Tops State Forest], Cobark Lookout, 5 Feb. 1996, M. Ito 96029, T. Nishino & Y. Kita (CANB, MEL!, NSW, TI); Barrington Trail, 0.6 km south of the Barrington Tops Forest Road, 27 Feb. 2009, J.R. Hosking 3204 (CANB, MEL, NE!, NSW, PERTH); Barrington Tops National Park, Gloucester Tops, 9 Apr. 2018, T.L. Collins 1041 (CANB!, BRI!, NE!, NSW!); Barrington Tops National Park, Polblue Swamp, 10 Apr. 2018, T.L. Collins 1044 (CANB!, BRI!, NE!, NSW!); Barrington Tops National Park, Bull Ridge Road, 10 Apr. 2018, T.L. Collins 1046 (CANB!, BRI!, NE!, NSW!); Careys Peak, Barrington Tops, 12 Feb. 1971, I.R. Telford 2729 (CANB!).

Fig. 35.

Distribution of Xerochrysum murapan.

Fig. 36.

Isotype of Xerochrysum murapan (J.R.Hosking 3201, NE 95474).

Xerochrysum neoanglicum J.J.Bruhl & I.Telford, sp. nov.

Type: AUSTRALIA: New South Wales: Northern Tablelands: 400 m N of Glencoe along New England Highway, E side of road, 8 Nov. 2002, L.M. Copeland 3468, J.J. Bruhl & I.R. Telford, (holo: NSW!; iso: BRI!, CANB!, K!, MEL!, NE 80118!, PERTH!, US!).

Xerochrysum bracteatum subsp. barringtonense MS, G.J. Harden, New South Wales Fl. Online (see  http://plantnet.rbgsyd.nsw.gov.au/floraonline.htm, accessed 21 May 2018).

Xerochrysum sp. Glencoe (M.Gray 4401) NE Herbarium, CHAH, Austral. Pl. Census (2020) [accessed 20 February 2020].

[Xerochrysum bracteatum auct. non (Vent.) Tzvelev: N.N. Tzvelev, Novosti Sist. Vyssh. Rast. 27: 151 (1990), p.p., populations with a solitary inflorescence, annually arising from a perennial crown and restricted to the New England Tablelands Bioregion and Barrington Tops, New South Wales only].

Selected specimens examined

QUEENSLAND: Darling Downs: Mount Norman, Wallangarra, 3 Oct. 1998, D. Hockings s.n. (BRI-AQ 663705!); Racecourse Creek Swamp, 25 km E of Mount Norman picnic area, 24 Dec. 1999, F.D. Hockings 1003 (BRI!). NEW SOUTH WALES: Northern Tablelands: Boonoo Boonoo, Resurrection Creek, at Mount Lindesay Road crossing, 8 Nov. 2010, I.R. Telford 13334 & T. Vollbon (BRI!, CANB!, K!, MEL!, MO!, NE!, NSW!, NY!, US!); E of Glencoe, Costello Road, 8 Dec. 2018, T.L. Collins 1146 (CANB!, NE!, NSW); 5.4 km N of Llangothlin along road to Ben Lomond, 12 Nov. 2005, L.M. Copeland 4006 (CANB, NE!, NSW, US); Little Llangothlin Nature Reserve, Billy Bung Lagoon, 20 Nov. 2005, I.R. Telford 12914 (CANB!, CHR!, MEL!, NE!, NSW!, US!); NE of Ebor along Waterfall Way, 17 Dec. 2016, J.J. Bruhl 3511 & I.R. Telford (NE!); Werrikimbe National Park, SW side of Racecourse Swamp, 13 Feb. 2003, L.M. Copeland 3561, J. Hodgon & I.R. Telford (CANB!, MEL!, NE!, NSW!, PERTH!); alongside Edwards Swamp Trail, north of Barrington River, 23 Feb. 2005, J.R. Hosking 2586 (CANB, MEL, NE!, NSW).

Fig. 37.

Distribution of Xerochrysum neoanglicum.

Fig. 38.

Isotype of Xerochrysum neoanglicum (L.M. Copeland 3468, J.J. Bruhl & I.R. Telford, NE 80118).

Xerochrysum papillosum (Labill.) R.J.Bayer, Kew Bull. 56(4): 1015 (2001)

Helichrysum papillosum Labill., Nov. Holl. pl. 2: 46 t. 192 (1806); Bracteantha papillosa (Labill.) Anderb. & Haegi, Opera Bot. 104: 105 (1991). Type citation: ‘in capite Van-Diemen.’ Type: In capite Van-Diemen [Tasmania], s. dat., J.J.H. de Labillardière s.n. (lecto, here designated: FI 006315*; probable isolecto: FI 006314*, MEL 61392*, G-DC G00470570*).

Erect, taprooted, perennial herb. Stems and branches cobwebby, hirsute, hispid, or glabrescent, and with glands; internode length 1–40 mm. Basal leaf rosette absent at flowering. Basal leaves spathulate, 50–120 mm long and 10–20 mm wide, base amplexicaul, margin cobwebby or hispid, apex apiculate and mucronate; basal leaf abaxial indumentum with glands, midvein glabrous (occasionally with scattered septate trichomes); adaxial indumentum hispid and with glands. Cauline leaves oblanceolate to lanceolate, 35–150 mm long and 3–10 mm wide, base subauriculate, margin cobwebby, hispid, scabrid, and with glands, apex apiculate and mucronate; abaxial indumentum with scattered septate trichomes and glands, midvein indumentum cobwebby, hispid, and with glands; adaxial indumentum hispid and with glands. Foliaceous bracts subtending capitula 10–35 mm long, margin cobwebby, hispid and with glands. Capitula 35–55 mm wide, terminal, in panicles or solitary. Outer phyllaries broad-ovate, pink, brown, or straw-coloured, basal margin fimbriate and hispid, abaxial surface smooth, apex acuminate to apiculate. Medial phyllaries narrow ovate to lanceolate, abaxially white or yellow, apex cuspidate or apiculate. Stylar appendages clavate to ovate. Cypsela ~2.8 mm long and 1 mm wide, cross-section squarish or circular; pericarp brown, idioblasts present. Pappus deciduous, ~7 mm long.

Selected specimens examined

VICTORIA: South Gippsland: Wilsons Promontory National Park, 10 Nov. 1983, A.C. Beauglehole 75352 (MEL!); South Cape Bay, 6 Apr. 1930, H.F. Comber 2278 (E 00231983!, HO). TASMANIA: Little Dog Island, Furneaux Group, 28 Aug. 1973, J.S. Whinray 186 (CANB!); Mount Chappell Island, Furneaux Group, 8 Feb. 1972, J.S. Whinray 222 (CANB!); Sea Lion Island, near its centre, 29 Aug. 1985, J.S. Whinray 8758 (CANB!); Flinders Island, slopes of Strzelecki Peaks, 28 Feb. 1977, B.C. Crisp 460 (CANB!); Mount Chappell Island, S end, 1 Nov. 1992, R. Burns 444 (CANB!); Mount Chappell Island, Mount Chappell, N face, 1 Nov. 1992, R. Burns 436 (CANB!); St Patricks Head State Reserve, upper slopes and summit, 6 Mar. 2018, T.L. Collins 1037 & R.L. Andrew (CANB!, HO!, NE!); Eaglehawk Neck, Tessellated Pavement, 28 Feb. 2018, T.L. Collins 1018 & R.L. Andrew (CANB!, HO!, NE!).

Fig. 39.

Distribution of Xerochrysum papillosum.

Xerochrysum strictum T.L.Collins & J.J.Bruhl, sp. nov.

Type: AUSTRALIA: Queensland: Atherton Tableland: Herberton – Irvinebank Road, ~6.2 km W of Atherton – Herberton road, 27 June 2018, T.L. Collins 1058 & J.J. Bruhl, (holo: BRI!; iso: CANB!, CNS!, NE 107426!).

Xerochrysum bracteatum subsp. (Mount Elliot A.R. Bean 3593), A.E. Holland in P.D. Bostock and A.E. Holland (eds), Census Queensl. Fl. 32 (2007); CHAH, Austral. Pl. Census (2020) [accessed 20 February 2020].

Xerochrysum sp. ‘Cockatoo Creek’, P.G. Wilson, Nuytsia 28: 13 (2017).

[Xerochrysum bracteatum auct. non (Vent.) Tzvelev: N.N. Tzvelev, Novosti Sist. Vyssh. Rast. 27: 151 (1990), p.p., populations of erect, perennial plants with hirsute cauline leaves with septate trichomes and stipitate glands on both abaxial and adaxial surfaces, in central and northern Queensland only].

Selected specimens examined

QUEENSLAND: Cook: McIlwraith Range, edge of scrub, north-west of campsite, 25 May 2003, D.L. Jones 18897 (CANB!); Herberton Range Ridge Road, 27 June 2018, T.L. Collins 1051 & J.J. Bruhl (BRI!, CANB!, CNS!, NE!); Herberton–Irvinebank road, 27 June 2018, T.L. Collins 1058 & J.J. Bruhl (BRI!, CANB!, CNS!, NE!); SSW of Wondecla, 1 July 2018, T.L. Collins 1063 & J.J. Bruhl (BRI!, CANB!, CNS!, NE!); Blackbraes National Park, 2 July 2018, T.L. Collins 1067 & J.J. Bruhl (BRI!, CANB!, CNS!, NE!). North Kennedy: ~17 km W of Paluma along road to Hidden Valley, 11 Nov. 2006, J.J. Bruhl 2473 (BRI!, NE!); ~700 m SSE of Mount Zero along high-tension power-line access track, 11 Nov. 2006, J.J. Bruhl 2477 & I.R. Telford (BRI!, NE!, NSW!); base of Roma Peak, ~40 km S of Bowen, 30 June 1991, A.R. Bean 3347 (BRI!); 21 km NW of Pentland on road to Lolworth Station, Hughenden, 24 July 1975, A.D. Chapman 1355 (BRI!, CANB). South Kennedy: Clarke Range, ~8 km NW of Eungella, 24 June 2014, I.R. Telford 13489, J.J. Bruhl & C.J. Prychid (BRI!, CANB!, NE!, US!). Leichardt: W lower slopes of Wolgang [Wolfgang] Peak, 17 Oct. 1983, R.J. Henderson H2912 & G.P. Guymer (CANB!).

Fig. 40.

Distribution of Xerochrysum strictum.

Fig. 41.

Isotype of Xerochrysum strictum (T.L. Collins 1058 & J.J. Bruhl, NE 107426).

Xerochrysum viscosum (Sieber ex DC.) R.J.Bayer, Kew Bull. 56(4): 1015 (2001)

Helichrysum viscosum Sieber ex Spreng., Syst. Veg. 3: 484 (1826); Helichrysum bracteatum var. viscosum Sieber ex DC., Prodr. 6: 189 (1838); Bracteantha viscosa (Sieber ex DC.) Anderb. & Haegi, Op. Bot. 104: 105 (1991). Type: Novae Holl. [New South Wales], Sieber 345 (lecto, fide P.G. Wilson, Nuytsia 28: 29 (2017): G-DC G00470540*, isolecto: HAL 0111515, MEL 604820, NY 00179176*, W 18890232748).

Erect, taprooted, perennial herb, up to ~60 cm tall. Stems and branches scabrid and with glands, internode length 5–20 mm. Basal leaf rosette absent at flowering. Basal leaves oblanceolate to spathulate, 50–120 mm long and 3–15 mm wide, base amplexicaul, margin hispid and with glands, apex apiculate; abaxial indumentum with glands, midvein glabrous (occasionally with scattered septate trichomes); adaxial indumentum pilose. Cauline leaves linear to oblanceolate, 20–80 mm long and 1–5 mm wide, base truncate, apex acute or apiculate and mucronate, margin hispid and with glands; abaxial indumentum with glands, midvein indumentum with glands (occasionally with scattered septate trichomes); adaxial indumentum hispid and with glands. Foliaceous bracts subtending capitula 4–8 mm long, margin with glands. Capitula 20–30 mm wide, terminal, in panicles or solitary. Outer phyllaries broad-ovate, brown or straw-coloured, basal margin fimbriate and hispid, abaxial surface smooth, apex acuminate or apiculate. Medial phyllaries oblong, ovate or narrow ovate, abaxially yellow, apex cuspidate or apiculate. Stylar appendages narrowly triangular or deltoid. Cypsela ~2.2 mm long and 0.7 mm wide, cross-section squarish or circular; pericarp brown, idioblasts present. Pappus deciduous, ~7–8 mm long.

Selected specimens examined

QUEENSLAND: Burnett: Coomba Falls, near Maidenwell, 25 Mar. 1997, P.I. Forster 20583 (BRI!). Darling Downs: 5 km from Wallangarra along New England Highway towards Stanthorpe, 21 Jan. 2009, I.R. Telford 13281 & J.J. Bruhl (BRI, CANB, NE!). NEW SOUTH WALES: Northern Tablelands: Torrington SRA, 16 Jan. 1997, C.E. Nano 48 (NE!); Oxley Wild Rivers National Park, Apsley Falls, 17 Feb. 2018, T.L. Collins 1014 (CANB!, NE!, NSW!). Central Western Slopes: Mudgee–Muswellbrook road, 16 Dec. 2017, T.L. Collins 1008 (CANB!, NE!, NSW!); Wellington, 2 km NE from summit of Mount Arthur, 10 May 2017, M.R. Thomas 28 (NE!). Central Tablelands: Western Highway, W of Lithgow, 16 Dec. 2017, T.L. Collins 1007 (CANB!, NE!, NSW!, US!). AUSTRALIAN CAPITAL TERRITORY: Black Mountain ACT, lower slope, 6 Dec. 2017, T.L. Collins 991 (CANB!, NE!, NSW!). VICTORIA: St Arnaud, 2 km SW of T-junction of Wimmera Highway with Dundas Street, 22 Oct. 2018, J.R. Nevin 164 (BRI!, CANB!, CHR!, MEL!, NE!, NSW!, US!); Warby-Ovens National Park, below road to Pine Gully Walk, 20 Dec. 2018, J.R. Hosking 4060 (AD!, CANB!, MEL!, NE!, NSW!).

Fig. 42.

Distribution of Xerochrysum viscosum.

Xerochrysum wilsonii T.L.Collins, sp. nov.

Type: AUSTRALIA: Western Australia: Darling: Porongurup National Park, upper slopes and summit of Devils Slide, 17 Dec. 2018, T.L. Collins 1160 (holo: PERTH!; iso: CANB!, NSW!, NE 108019!).

[Xerochrysum macranthum auct. non (Benth.) Paul G.Wilson: A.N. Schmidt-Lebuhn et al., Taxon 64(1): 105 (2015), p.p., populations of perennial plants in the Esperance, Jarrah Forest and Warren bioregions with mid-cauline leaves ≥12 mm wide only].

Selected specimens examined

WESTERN AUSTRALIA: Darling: Stirling Range National Park, summit of Bluff Knoll, 16 Dec. 2018, T.L. Collins 1157 (CANB!, K!, NE!, PERTH!, US!); Stirling Range National Park, summit of Toolbrunup, 16 Dec. 2018, T.L. Collins 1158 (CANB!, NE!, PERTH!); Walpole–Nornalup National Park, Conspicuous Cliffs, 18 Dec. 2018, T.L. Collins 1161 (CANB!, K!, NE!, NSW!, PERTH!, US!); Walpole–Nornalup National Park, Delta Road, 18 Dec. 2018, T.L. Collins 1162 (CANB!, NE!, PERTH!); Collier Peak, Porongurup Range, 20 Nov. 1987, G.J. Keighery 8722 (PERTH!); Yallerungup Peak, Porongurup Range, 15 Dec. 1986, G.J. Keighery 8419 (PERTH!); Mount Many Peaks, 4 Oct. 1994, S. Barrett 24 (PERTH!).

Fig. 43.

Distribution of Xerochrysum wilsonii.

Fig. 44.

Isotype of Xerochrysum wilsonii (T.L.Collins 1160, NE 108019).

Xerochrysum milliganii group

Xerochrysum alpinum Paul G.Wilson, Nuytsia 28: 36 (2017)

Type: Lake Lea Road, Tasmania, 17 Feb. 1998, A.M. Buchanan 15101 (holo: HO 324393).

Erect, perennial, rhizomatous herb up to 20 cm. Stems and branches cobwebby and with glands, internode length 10–35 mm. Basal leaf rosette present at flowering. Basal leaves obovate, 20–60 mm long and 10–25 mm wide, base attenuate, margin cottony and with glands, apex apiculate; abaxial indumentum with glands, midvein glabrous; adaxial indumentum hispid and with glands (hispid indumentum on midvein basally). Cauline leaves obovate, 20–50 mm long and 1–3 mm wide, base attenuate, margin cobwebby or cottony, apex apiculate; abaxial indumentum with glands, midvein indumentum with glands; adaxial indumentum with glands. Foliaceous bracts subtending capitula 10–12 mm long (with fimbriate apical hairs), margin cobwebby and with glands. Capitula 30–45 mm wide, terminal, solitary. Outer phyllaries ovate, straw-coloured, basal margin fimbriate, extending to apex, abaxial surface scabridulous towards apex, apex fimbriate. Medial phyllaries lanceolate, abaxially yellow, apex cuspidate. Stylar appendages clavate. Cypsela 2.3 mm long and 0.75–1 mm wide, cross-section with oblique angles; pericarp grey–brown, idioblasts absent. Pappus persistent, ~5–6 mm long.

Selected specimens examined

TASMANIA: Vale of Belvoir Conservation Reserve, Lake Lee Road, 2 Mar. 2018, T.L.ttp://anpsa.org.au/APOL2006/ju Collins 1024 & R.L. Andrew (CANB!, HO!, NE!); Cradle Mountain National Park, Face Track, 3 Mar. 2018, T.L. Collins 1030 & R.L. Andrew (CANB!, HO!, NE!), summit of Blue Tier, 23 Feb. 1878, A. Simson 1101 (MEL 0061148A).

Fig. 45.

Distribution of Xerochrysum alpinum.

Xerochrysum andrewiae T.L.Collins & J.J.Bruhl, sp. nov.

Type: AUSTRALIA: Tasmania: Ansons Bay Road, ~4.5 km N of Reids Road, SW side of road, ~70 m from road edge, 6 Mar. 2018, T.L. Collins 1036 & R.L. Andrew, (holo: HO!; iso: CANB!, NE 106812!).

[Xerochrysum subundulatum auct. non (Sch.Bip.) R.J.Bayer: R.J. Bayer, Kew Bull. 56(4): 1015 (2001) p.p., only populations with stipitate glands on cauline leaves adaxially].

[Bracteantha palustris auct. non Flann: C. Flann, Muelleria 11: 97 (1998), p.p., populations with smooth outer phyllaries only; Xerochrysum palustre auct. non (Flann) R.J.Bayer: R.J. Bayer, Kew Bulletin 56(4): 1014 (2001), p.p., populations with smooth outer phyllaries only].

Selected specimens examined

NEW SOUTH WALES: Central Tablelands: Kanangra Walls, 22 Mar. 2011, R. Johnstone 2906 (BRI, CANB, MEL!, NSW!); Kanangra Boyd National Park, 19 Apr. 2015, J. Miles 15–50 (NSW!); Kanangra Walls Road, 12 Jan. 2001, D.L. Jones 17798 (CANB*, MEL, NSW); Jensens Swamp, 1 Mar. 1985, D.H. Benson 2330 (NSW!). South Coast: Coolumbooka Nature Reserve, 30 Apr. 2002, I. Crawford 7018 (CANB!); on Outskirt Creek tributary arm in NW corner of Bondi or Mountain Top Travelling Stock Reserve, 16 Feb. 2015, J. Miles 15–27 (NSW!); Bega Swamp at the head of Brogo River, 6 May 1976, R. Pullen 10268 (CANB!, NSW); ~9.8 km E of Cathcart towards Pambula, 8 Feb. 2000, D.L. Jones 17157 (MEL!); Badja State Forest, 12 Feb. 2004, N.G. Walsh 6006 (MEL!); 17.8 km E of Braidwood–Clyde Mountain, 19 Mar. 2006, D.L. Jones 19352 (CANB, MEL!). VICTORIA: East Gippsland: Alpine National Park, Playgrounds, 10 Feb. 2005, N.G. Walsh 6260 (MEL!); Alpine National Park, Cowombat Flat Track, 10 Feb. 2005, N.G. Walsh 6258 (MEL!); Snowy River National Park, 11 Jan. 1993, I.R. Telford 11782 (CANB*, MEL); Bidwell, Upper Delegate River, 19 Jan. 1953, R. Melville 2959 (MEL!, NSW). TASMANIA: North East: Break O’Day: Bells Marsh, 13 Apr. 2009, M. Wapstra 714 (HO!); Powers Rivulet Marsh, 12 May 2009, M. Wapstra 717 (HO!); unnamed marsh, W of Ansons Bay Road, 13 Apr. 2009, M. Wapstra 715 (HO!).

Fig. 46.

Distribution of Xerochrysum andrewiae.

Fig. 47.

Isotype of Xerochrysum andrewiae (T.L.Collins 1036 & R.L.Andrew, NE 106812).

Xerochrysum collierianum A.M.Buchanan, Muelleria 20: 49 (2004)

Type: St Valentines Peak, Tasmania, 13 Jan. 1986, P. Collier 1206 (holo: HO 116970).

Erect, perennial, fibrous-rooted herb up to ~25 cm. Stems and branches hirsute or glabrescent, and with glands; internode length 10–35 mm. Basal leaf rosette present or absent at flowering. Basal leaves obovate to spathulate, 20–80 mm long and 5–10 mm wide, base amplexicaul, margin cobwebby or hirsute, apex mucronate or apiculate; abaxial indumentum with glands, midvein indumentum with glands; adaxial indumentum hirsute and with glands. Cauline leaves oblanceolate, 20–40 mm long and 3–7 mm wide, leaf base attenuate, margin cobwebby or woolly, and hispid; apex mucronate; abaxial indumentum with glands, midvein indumentum with glands; adaxial indumentum hirsute and with glands. Foliaceous bracts subtending capitula 7–12 mm long, margin cobwebby or hispid. Capitula 30–40 mm wide, terminal, solitary. Outer phyllaries ovate, white, basal margin fimbriate or hispid, abaxial surface smooth, apex acute. Medial phyllaries narrow ovate to lanceolate, abaxially white, apex apiculate. Stylar appendages ovate. Cypsela ~2.5 mm long and 0.75 mm wide, cross-section with oblique angles; pericarp brown, idioblasts indistinct. Pappus persistent, ~6 mm long.

Selected specimens examined

TASMANIA: Central Highlands: Mount Claude Lookout track from Olivers Road, 2 Mar. 2018, T.L. Collins 1026 & R.L. Andrew (CANB!, HO!, NE!); on rocky outcrop at intersection of Mount Claude Lookout track and Olivers Road, 2 Mar. 2018, T.L. Collins 1027 & R.L. Andrew (CANB!, HO!, NE!); Cradle Mountain National Park, 3 Mar. 2018, T.L. Collins 1032 & R.L. Andrew (CANB!, HO!, NE!).

Fig. 48.

Distribution of Xerochrysum collierianum.

Xerochrysum milliganii (Hook.f.) Paul G.Wilson, in A.N.Schmidt-Lebuhn et al., Taxon 64: 106 (2015)

Helichrysum milliganii Hook.f., Fl. Tasman. 1: 214 t. LX. B. (1856). Type: Mount Sorell [sic], Macquarie Harbour [Tasmania], 15 Jan. 1847, J. Milligan 755 (lecto, designated by A.N. Schmidt-Lebuhn et al., Taxon 64: 106 (2015): K 000928522*; isolecto: K 000928518, K 000928519, K 000928520, MEL 1585997; residual syntype: Mount Pearse, Surrey Hills, Tasmania, s. dat., R.C. Gunn 1169 (K)).

Erect, fibrous-rooted, perennial herb, up to 20 cm. Stems and branches cobwebby, or woolly, or glabrescent; internode length 5–20 mm. Flowering stems unbranched. Basal leaf rosette present at flowering. Basal leaves obovate, 10–15 mm long and 3–6 mm wide, base amplexicaul, apex acute, margin cobwebby and with glands; abaxial leaf surface glabrous, midvein glabrous; adaxial indumentum with scattered glands. Leaf arrangement cauline or radical. Cauline leaves oblanceolate or lanceolate, 15–25 mm long and 3–5 mm wide, base truncate, apex acute, margin cobwebby, or glabrous, or woolly; abaxial indumentum cobwebby, midvein indumentum cobwebby; adaxial indumentum with scattered glands. Foliaceous bracts subtending capitula 5–7 mm long, margin cobwebby or fimbriate. Capitula 30–40 mm wide, terminal, solitary. Outer phyllaries white, basal margin cobwebby or fimbriate, abaxial surface smooth, apex acute. Medial phyllaries abaxially white, apex cuspidate or apiculate. Stylar appendages clavate. Cypsela ~3 mm long and ~0.75 mm wide, cross-section squarish; pericarp grey–brown, idioblasts absent. Pappus persistent, ~6 mm long.

Selected specimens examined

TASMANIA: Central Highlands: Cradle Mountain National Park, upper slope of Marions Lookout, 3 Mar. 2018, T.L. Collins 1028 & R.L. Andrew (CANB!, HO!, NE!); Cradle Mountain National Park, Face Track, 3 Mar. 2018, T.L. Collins 1029 & R.L. Andrew (CANB!, HO!, NE!); Mount Rufus, 25 Jan. 1949, N.T. Burbidge 3341 (CANB*). Huon Valley: Moonlight Ridge, hill one, 31 Jan. 1983, P.S. Short 1873 (CANB*, MEL); Adamsons Peak, 7 Feb. 1969, I.R. Telford EMC2480 (CANB!, PERTH).

Fig. 49.

Distribution of Xerochrysum milliganii.

Xerochrysum palustre (Flann) R.J.Bayer, Kew Bull. 56(4): 1014 (2001)

Bracteantha palustris Flann, Muelleria 11: 97 (1998). Type: Saplings Morass Flora and Fauna Reserve, Victoria, 11 Dec. 1996, C. Flann 1 & N.G. Walsh (holo: MEL 2036150*; iso: CANB 528907*, NSW 458152).

Helichrysum acuminatum var. angustifolium DC., Prodr. 6: 188 (1838). Type citation: ‘in terra Van-Diemen legit cl. Gunn.’ Type: van Diemen, s. dat., Gunn 247 (syn: G-DC G00470645*); In insula Van Diemen, s. dat., ?Gunn s.n. (possible syn: MEL 61301*).

Erect, rhizomatous, perennial herb, ~30–60 cm tall. Stems and branches cobwebby or woolly to glabrescent, and with glands; internode length 15–35 mm. Basal leaf rosette absent at flowering. Seedling and basal leaves not seen. Cauline leaves lanceolate, 20–120 mm long and 2–10 mm wide, base attenuate, margin cobwebby, hispid, and scabrid, apex acute and apiculate; abaxial indumentum with glands, midvein glabrous (occasionally with scattered septate trichomes and glands); adaxial indumentum cobwebby or glabrous, and with glands. Foliaceous bracts subtending capitula 5–10 mm long, margin cobwebby and fimbriate. Capitula 35–45 mm wide, terminal, solitary. Outer phyllaries ovate, brown or straw-coloured, basal margin fimbriate and hispid, abaxial surface smooth, apex acute to apiculate. Medial phyllaries lanceolate, abaxially brown or yellow, apex apiculate to acute. Stylar appendages clavate to ovate. Cypsela oblong, ~3 mm long and ~0.75 mm wide, in cross-section with oblique angles to circular; pericarp brass-coloured, idioblasts present. Pappus persistent, ~8 mm long.

Selected specimens examined

NEW SOUTH WALES: South Coast: corner Tin Mine Road and Tantawangalo Mountain Road, 17 Jan. 2000, D.L. Jones 17111 (CANB, NE!); ~9.8 km E of Cathcart towards Pambula, 8 Feb. 2000, D.L. Jones 17157 (CANB, MEL!). VICTORIA: East Gippsland: Gisborne Racecourse Marshlands Reserve, 12 Dec. 1996, C. Flann 5 & N.G. Walsh (MEL!). Western Plains: Lower Glenelg River area, Red Gum Flat, 25 Jan. 1970, A.C. Beauglehole 33395 (MEL!). TASMANIA: Central Highlands: Bronte Lagoon, 1 Mar. 2018, T.L. Collins 1019 & R.L. Andrew (CANB!, HO!, NE!). Northern Midlands: Smiths Lagoon, 7 Mar. 2018, T.L. Collins 1038 & R.L. Andrew (CANB!, HO!, NE!).

Fig. 50.

Distribution of Xerochrysum palustre.

Xerochrysum subundulatum (Sch.Bip.) R.J.Bayer, Kew Bull. 56(4): 1015 (2001)

Helichrysum acuminatum DC., Prodr. 6: 188 (1838), nom. illeg., non (Link) Sweet (1826); Gnaphalium subundulatum Sch.Bip., Bot. Zeitung 3: 171 (1845), nom. nov.; Bracteantha acuminata Anderb. & Haegi, Op. Bot. 104: 105 (1991), nom. illeg., nom. superfl.; Bracteantha subundulata (Sch.Bip.) Paul G.Wilson, Muelleria 7(4): 519 (1992). Type citation: ‘ad terram Van-Diemen legit cl. Gunn’. Type: Van-diemen [Tasmania], R.C. Gunn 244 (syn: G-DC G00470677*); Van Diemensland, leg. ign., s. dat. (possible syn: MEL 61149*).

Procumbent or erect, rhizomatous, perennial herb. Stems and branches cobwebby, woolly, or glabrescent, and with glands; internode length 10–30 mm. Basal leaf rosette present or absent at flowering. Basal leaves obovate to spathulate, 20–60 mm long and 6–20 mm wide, base amplexicaul, margin cobwebby or villous, apex apiculate; abaxial indumentum with glands, midvein indumentum cobwebby or villous; adaxial indumentum cobwebby, hispid, and with glands. Cauline leaves oblanceolate to obovate, 25–90 mm long and 5–20 mm wide, base attenuate and amplexicaul, margin cobwebby or hispid, apex apiculate and mucronate; abaxial indumentum hirsute, glabrescent and with glands; abaxial midvein indumentum cobwebby, hispid, and with glands; adaxial indumentum hispid, scabrid, and with glands. Foliaceous bracts subtending capitula 12–15 mm long, margin cobwebby, hispid and with glands. Capitula 35–50 mm wide, terminal, solitary. Outer phyllaries ovate to broad-ovate, orange, brown, or straw-coloured; basal margin hispid, abaxial surface scabridulous, apex acute. Medial phyllaries narrow ovate to lanceolate, abaxially yellow, apex acute. Stylar appendages ovate. Cypsela ~3 mm long and 1 mm wide, cross-section with oblique angles; pericarp brown, idioblasts present. Pappus persistent, ~7.5 mm long.

Selected specimens examined

AUSTRALIAN CAPITAL TERRITORY: Namadgi National Park, Cotter Hut Road, 3 Jan. 2007, J.J. Bruhl 2595 & I.L. Crawford (CANB!, NE!, NSW!). NEW SOUTH WALES: Southern Tablelands: Kosciuszko National Park, alongside Tooma Road, 25 Mar. 2014, J.R. Hosking 3746 (CANB, MEL, NE!, NSW, US). VICTORIA: unincorporated: Panorama Hill, Falls Creek, near the top of the Panorama Poma, 11 Mar. 1984, D.E. Albrecht 263 (MEL!). Alpine: Mount Buffalo National Park, 19 Jan. 1988, A.C. Beauglehole 92582 (MEL!). East Gippsland: Bogong High Plains, Buckety Plain, 20 Jan. 1988, N.G. Walsh 2021 (MEL!). TASMANIA: Ben Lomond: Ben Lomond National Park, 5 Mar. 2018, T.L. Collins 1035 & R.L. Andrew (CANB!, HO!, NE!). Central Highlands: Central Highlands Highway, Little Pine Lagoon, 1 Mar. 2018, T.L. Collins 1020 & R.L. Andrew (CANB!, HO!, NE!); Liaweeni, 1 Mar. 2018, T.L. Collins 1021 & R.L. Andrew (CANB!, HO!, NE!); Lake Augusta, 1 Mar. 2018, T.L. Collins 1022 & R.L. Andrew (CANB!, HO!, NE!); Cradle Mountain National Park, Face Track, 3 Mar. 2018, T.L. Collins 1031 & R.L. Andrew (CANB!, HO!, NE!).

Fig. 51.

Distribution of Xerochrysum subundulatum.

Entities of the Xerochrysum bracteatum group requiring further study

Xerochrysum sp. Blackfellows Gap (N.T.Burbidge 6926) Qld Herbarium

Low-growing, rhizomatous, perennial herb. Cauline leaves lanceolate, margin revolute and hispid with stipitate glands, apex acuminate to acute, and mucronate. Abaxial lamina indumentum with sessile glands, midvein indumentum hispid; adaxial lamina indumentum hispid and with glands. Outer phyllaries smooth, medial phyllaries oblong to ovate, abaxially yellow. Cypsela ~3 mm long and 1 mm wide; pericarp brown, idioblasts absent. Pappus deciduous, ~9 mm long.

Xerochrysum sp. Chinchilla (A.N.Schmidt-Lebuhn 1745) NE Herbarium

Erect, annual or biennial, taprooted herb. Cauline leaves oblanceolate, margin cobwebby and hispid, apex acute and mucronate. Abaxial indumentum with glands, midvein indumentum hispid and with glands; adaxial indumentum cobwebby, hispidulous and with glands. Medial phyllaries oblong to ovate, abaxially yellow.

Xerochrysum sp. North Stradbroke Island (L.Durrington 675) Qld Herbarium

Helichrysum macrocephalum A.Cunn ex DC., Prodr. 6: 188 (1838). Gnaphalium macrocephalum (A.Cunn. ex DC.) Sch.Bip., Bot. Zeit. 3: 17 (1845). Type: Sandy shores of Moreton Bay, N.S. Wales [Queensland] lat. 27.5 S, Oct. 1824, A. Cunningham 121 (holo: G-DC G00328540*).

Xerochrysum bracteatum subsp. (North Stradbroke Island L.Durrington 675), A. E. Holland in P.D. Bostock and A.E. Holland (eds), Census Queensl. Fl. 32 (2007).

Erect, perennial, tap-rooted herb. Cauline leaves obovate, margin cobwebby, hispid and scabrid, apex obtuse and mucronate. Abaxial indumentum with glands, midvein indumentum hispid with scattered glands; adaxial indumentum hispid and scabrid. Medial phyllaries ovate to narrow ovate, abaxially yellow.

Xerochrysum sp. Tin Can Bay (T.L.Collins 1116) NE Herbarium

Erect, perennial, tap-rooted herb. Cauline leaves oblanceolate to lanceolate, margin cobwebby and hispid, apex acuminate to acute, and mucronate. Abaxial indumentum with glands, midvein indumentum hispid with scattered glands; adaxial indumentum cobwebby, hispid, and with glands. Medial phyllaries ovate to narrow ovate, abaxially orange, brown, or yellow.