Recent molecular phylogenetic analyses prompted recircumscription of Pandanales into five families—Cyclanthaceae, Pandanaceae, Stemonaceae, and Velloziaceae, plus the mycoheterotrophic Triuridaceae—that were not hitherto regarded as closely related and so have not previously been compared in detail. Some species exhibit anomalous floral features, including apparently secondary apocarpy, loss of trimery, and an imprecise boundary between inflorescence and flower. Most noteworthy are the female reproductive structures of Triuridaceae, especially the “inside-out” flowers of Lacandonia. A phylogenetic cladistic analysis using 39 morphological characters of 23 genera spanning all five families of Pandanales yielded three fairly well-resolved and moderately supported most-parsimonious trees. Velloziaceae were sister to all other Pandanales. Cyclanthaceae and Pandanaceae formed a sister pair that was sister to Stemonaceae plus Triuridaceae. Triuridaceae were embedded within a paraphyletic Stemonaceae. Pentastemona was sister to all other Stemonaceae plus Triuridaceae, supporting earlier suggestions that this highly divergent genus should be recognized as a separate family, Pentastemonaceae. Kupea was robustly placed as the basally-divergent node of Triuridaceae, upholding an earlier hypothesis that the biovulate condition in Kupea could represent the ancestral condition for Triuridaceae. Contrasting models are outlined for interpretation of the unusual apocarpous female floral units of Triuridaceae, either as (1) highly reduced partial inflorescences (pseudanthia), (2) inflorescence-like flowers derived by carpel multiplication (delayed determinacy) from an ancestor with a single free carpel (with flowers similar to those of Croomia, but unisexual), or (3) flowers derived from a tricarpellate syncarpous ancestor (with flowers similar to those of Pentastemona, but unisexual) by loss of carpel fusion and carpel multiplication. The formerly unsuspected close relationship between Stemonaceae and Triuridaceae supports the second model. The indistinct inflorescence—flower boundary in Triuridaceae could be attributable to an overlap in genetic programs, resulting either from a partial loss of integrity in regulation of flower development or from extreme axial condensation associated with the mycoheterotrophic habit.

The role of flowering phenology in ecological diversification is poorly understood, even though this variable may be an important determinant of fitness. While flowering schedules are readily evolvable, they also seem to be under phylogenetic constraint. I ask whether phenological change is a partner to adaptive radiation. Using examples from island and continental lineages, I show that habitat diversifications are not necessarily coupled with phenological change, whereas shifts in pollinator typically are so coupled. It all depends on whether alteration in flowering time is required to invade new habitats or exploit new pollinators. The coupling of ecological and temporal shifts is most evident in the evolution of autopolyploids. Stasis in the flowering times of some lineages more likely is due to stabilizing selection than to genetic constraints.

The moss genus Pohlia is most diverse in the Northern Hemisphere, but ten species occur in Australia, mostly in New South Wales and Tasmania. One species, P. clavaeformis, is endemic to Australia; P. tenuifolia is disjunct between Australia and South America; P. flexousa is widespread in southern Asia, and P. inflexa is high-latitude, circum-Antarctic. The remaining six species are more or less widespread in the Northern Hemisphere. Keys, descriptions, synonomy, and illustrations are provided. Pohlia mielichoferia and P. turgens are newly synonymized with P. clavaeformis; P. flexuosa and P. inflexa are newly reported from Australia.

The ancient divergence between the lycopsid genus Isoëtes and its closest living relative (Selaginella) has resulted in considerable morphological and genetic disparity, yet within Isoëtes there is remarkable morphological and genetic uniformity. This has made it difficult to identify the phylogenetic root of the genus. In this study, we addressed this problem and characterized the early branching patterns within Isoëtes using an expanded set of taxa and three molecular markers. We assessed the saturation in the molecular data sets, tested for differences in evolutionary rate, determined the stability of the ingroup topology, and evaluated the applicability of the molecular clock. We then explored three alternative rooting approaches: outgroup, midpoint, and maximum likelihood under the assumption of a molecular clock. Attempts to infer the root of Isoëtes using the outgroup approach were severely hindered by the effects of saturation, but the results from midpoint rooting and the enforcement of the molecular clock were highly consistent among the data sets. We identify the root of Isoëtes to be located among three major, highly supported clades.

With more than 100 species, Mecodium is the largest infrageneric taxon of Hymenophyllum s.l. It was long considered a natural and homogeneous group, but recent phylogenetic studies have questioned this assertion. Using rbcL, rbcL-accD, and rps4-trnS sequences, we demonstrate that Mecodium is highly polyphyletic. Several species of Mecodium form the derived clade “H. polyanthos”; one species is nested within a second derived clade; and the remaining species are assigned to five basal clades including taxa regarded as distantly related. These clades are strongly supported both by parsimony and Bayesian analyses, but the relative placement of the basalmost clades lacks support. We show that the members of “basal Mecodium” are characterized by features that are plesiomorphic for Hymenophyllum s.l.—a reduced or dorsi-ventral stele, a lamina generally at least partially thickened, and a chromosome number based on x = 36, whereas taxa in the “H. polyanthos” clade have a subcollateral stele, the one-cell thick lamina typical of the family, and x = 28. There is a high level of variation among the basal species, and, notably, the rhizome indumentum is shown to be an interesting character for distinguishing among the basal clades. These new findings stress the need for further studies on Hymenophyllum s.l., and reassessment of its classification.

A comprehensive taxonomic revision of the Philippine representatives of the genus Cyathocalyx (Annonaceae) is presented for the first time. Five species are recognized, including two endemics that are newly described (C. crassipetalus and C. samarensis). The utility of specific taxonomic characters is also evaluated, with particular emphasis on leaf indument and occurrence of crystals; sepal and petal shape; carpel number; monocarp size and shape; pericarp thickness; presence of stipes; seed size and shape; and prominence of the raphe. The conservation status of each species is evaluated according to current IUCN Red List categories and criteria.

A new species, Clara gracilis (Herreriaceae), endemic to the Rio Grande do Sul State, Brazil, is described and compared to the closely related C. ophiopogonoides. A key for separating the three species of the genus is presented, with a map of their geographic distribution, as well as detailed illustrations of the new species.

Five character construction methods were compared for a data set of 25 quantitative morphological characters sampled from the Govenia superba complex. The methods were simple-gap, gap coding, gap-weighting, analysis of variance followed by a multiple range test, and an “arbitrary” coding method. Three indices, data decisiveness, consistency index, and skewness (g₁), were used as estimators of phylogenetic signal. Performance of coding methods was evaluated by the following criteria: (1) number of informative characters, (2) number of equally parsimonious trees, (3) clade support measured by bootstrapping, and (4) phylogenetic signal, compared using randomization tests that established critical values for the three indices and allowed them to be compared between coding methods. This study demonstrates that a large number of characters are accessible for phylogenetic analysis when continuous characters are included. The quantitative character data for the Govenia complex contain significant phylogenetic information when the gap-weighting method is used to construct character states. This indicates that methods that divide variation into small segments and allow overlapping of measurements recover a strong phylogenetic signal, and yield small number of well-resolved trees with strong bootstrap support and statistically significant phylogenetic signal. In contrast, methods such as gap coding or analysis of variance-multiple range test lead to data matrices with few informative characters and many equally parsimonious trees and weak phylogenetic signal. Moreover, the simple-gap coding method data matrix failed to recover significant phylogenetic signal.

The taxonomic position of Hectorella caespitosa and Lyallia kergelensis, caespitose plants endemic to New Zealand and to the Kerguélen Archipelago of Antarctica, respectively, remains controversial. Some authors place them within Portulacaceae, but a slight majority of recent authorities treat them as a separate family, Hectorellaceae. Sequences of the chloroplast genes rbcL, ndhF, and matK were obtained from H. caespitosa and added to previously published sequences from Portulacaceae and related families. These data strongly supported the derived position of Hectorella within a clade consisting of western American members of Portulacaceae; the sister group of Hectorella was a clade including Montia, Claytonia, and Lewisia. Implications for taxonomy are discussed. In order to accomodate monophyly in tribal-level classification while preserving current tribes Montieae and Lewiseae, the new tribe Hectorelleae is proposed for the family Portulacaceae.

The monotypic genus Algrizea is described from the Chapada Diamantina highlands, in Bahia, Brazil, and a new combination, Algrizea macrochlamys, is proposed. This species was well-known from flowering material but fruits and seeds, essential for accurate generic placement, were unknown until 2000. Treated successively as Myrcia, Myrtus, and more recently as Psidium, it combines characters usually considered primitive in the Myrtaceae with an unusual embryo unlike any hitherto described in the Myrtaceae. Morphological and preliminary molecular data suggest that it is best accommodated in the Myrciinae sensu stricto. Algrizea is distinguished by the combination of 3-flowered dichasia, persistent bracteoles, 5 well-developed calyx lobes, bilocular ovaries with 3–6(-8) ovules per locule, seeds 2–3 with membranous, shiny testa, and an embryo in which the hypocotyl assumes an internal position to the unequal, sheathing cotyledons.

While most Begonia species have a similar fruit morphology that shows adaptations to wind dispersal, a few species have atypical fruits and are adapted to either animal or rain dispersal. Such differences in fruit morphology have traditionally been emphasized in sectional classifications of Begonia and some of the currently recognized sections can only be distinguished using ovary and fruit characteristics. We evaluated the monophyly and evolution of three Asian sections with atypical fruit morphologies: Platycentrum, Sphenanthera, and Leprosae, along with members of nine other Asian sections with fruit morphologies typical of wind dispersed Begonia. A parsimony analysis of nrDNA ITS/ 5.8S sequence data of 46 Asian Begonia species suggests that the members of section Platycentrum, which have fruit morphologies indicative of rain dispersal, evolved from wind dispersed Asian taxa following the colonization of wetter habitats. From within this rain dispersed group, species of section Sphenanthera with fleshy, animal dispersed fruits subsequently evolved on multiple occasions. Members of section Leprosae, which have fleshy fruit, evolved on two separate occasions, in one case independently of the members of the sections Platycentrum and Sphenanthera. As currently recognized, sections Platycentrum, Sphenanthera and Leprosae are polyphyletic.

Poupartiopsis spondiocarpus, a modest-sized tree of littoral forests of eastern Madagascar, is recognized as a distinct genus and described. Emended descriptions and circumscriptions of the recognized subfamilies Spondioideae and Anacardioideae are provided, as are separate keys to the genera of Spondioideae based on flowering and fruiting material and a table of diagnostic characters for distinguishing the genera. Molecular phylogenetic analysis and structural data including leaf architecture, floral morphology, and endocarp structure place Poupartiopsis in the Spondioideae, one of two subfamilies in Anacardiaceae.

Under the criterion of limited homogenizing gene flow as evidenced through specimen aggregation analysis, and genetic evidence of a barrier to gene exchange with its closest relatives, we describe a new species in Polemoniaceae, Collomia wilkenii. Collomia wilkenii superficially resembles Collomia tinctoria and Collomia linearis in some features, but, upon examination, has consistent, unique character combinations that distinguish it from both species, as well as from sympatric Collomia renacta and Collomia tenella. These features include particulars of calyx morphology, corolla morphology, stamen insertion and exertion, numbers of flowers in inflorescence clusters, and the kinds and distribution of glandular and eglandular trichomes. Comparative DNA sequencing of chloroplast genes indicates Collomia wilkenii has the chloroplast genome of Collomia tenella. Nuclear ITS sequences show additivity in Collomia wilkenii between Collomia linearis and Collomia tenella, a pattern confirmed by cloning this region. Two low copy nuclear loci, idh-A and idh-B, indicate an allopolyploid origin of this previously undescribed species. Collomia wilkenii is endemic to northern Nevada, occurring in several locations across the breadth of the state.

Auxemma, Patagonula, and Saccellium (Cordiaceae, Boraginales) were all described as distinct from Cordia because of highly specialized fruit morphologies, and subsequent authors have almost universally continued to maintain them. However, both molecular and morphological data indicate that they are nested within Cordia, and the nomenclatural changes necessary to accommodate them in Cordia are proposed here. Complete synonomy, a key to all species formerly belonging to Auxemma, Patagonula, and Saccellium, and notes on their distributions as inferred from modern collections are provided.

Centaurium bianoris (Gentianaceae) is restricted to Majorca, the main island of the Balearic Archipelago. This tetraploid species is characterised by salmon-coloured corollas (var. bianoris), but pink (var. roseum) and yellow (var. sulfureum) varieties have also been described. An allopolyploid origin has been proposed between the diploids C. maritimum (yellow flowers) and C. tenuiflorum var. acutiflorum (pink flowers), both occurring on Majorca and in other places of the Mediterranean basin. In this study, we tested the proposed hybrid origin of C. bianoris by using RAPD fingerprinting, and both direct and cloned sequences of the nuclear ribosomal ITS, and the chloroplast trnLF regions. Our molecular data confirmed the hypothesis of an allotetraploid origin of C. bianoris via hybridisation between C. tenuiflorum and C. maritimum, the latter being the maternal parent. The so-called varieties roseum and sulfureum appeared to be only floral morphs that may have arisen via genomic processes such as gene silencing. Hybridisation is probably the cause of the ITS sequence polymorphism observed in C. bianoris, whereas backcrosses with either parent may be responsible for the apparent bidirectional homogenisation observed in ITS clones. Finally, the polyphyletic behaviour of C. bianoris on the ITS cladogram, combined with the differential rates of homogenisation observed in ITS sequences, may denote a recurrent origin for that taxon. This result contrasts with the narrow distribution of C. bianoris, compared to that of its diploid parents, suggesting instead a single origin for this hybrid.

The Mimulus moschatus alliance consists of 13 morphologically similar species, the majority of which have been considered for conservation protection. Phylogenetic analyses of four rapidly evolving molecular DNA regions (ITS, ETS, trnL-F, and rpl16) and a morphological data set under several optimality criteria reveal that the M. moschatus alliance is composed of three geographically defined clades: the Sierra Nevada Clade (M. floribundus, M. norrisii, and M. dudleyi), the Snake River Clade (M. hymenophyllus, M. ampliatus, and M. patulus), and the Columbia River Clade (M. washingtonensis and M. jungermannioides). The relationships within and among the clades are well resolved. Numerous instances of morphological homoplasy among the clades are inferred, including three independent origins of the autogamous mating system. Although nearly half of the morphological characters are highly homoplasious, the inclusion of morphological data in the combined maximum parsimony and Bayesian analyses improves topological resolution and branch support. The phylogenetic results support the specific recognition of three rare taxa (M. ampliatus, M. patulus, and M. dudleyi), previously synonymized with more widespread species. A key to the species within the M. moschatus alliance is provided.

Collinsonia (Lamiaceae) is a small genus restricted to eastern North America with four species commonly recognized: C. canadensis, C. serotina, C. tuberosa, and C. verticillata. Considerable taxonomic confusion exists within subgenus Collinsonia (all taxa except C. verticillata). Principal components and canonical variates analysis were performed on a macromorphological dataset of 23 variables scored for 118 specimens of subgenus Collinsonia. Results from field and herbarium observations and from the phenetic analyses indicate that specimens of C. serotina with four stamens (hereafter referred to as C. anisata) represent a distinct species. Specimens of C. serotina with two stamens are intermediate between C. canadensis and C. anisata and are tentatively recognized as C. punctata; further study is needed to determine their origin and evolutionary status. Collinsonia tuberosa and C. canadensis show considerable phenetic overlap and are here merged under C. canadensis. Four species of Collinsonia are now recognized: C. anisata, C. canadensis, C. punctata, and C. verticillata.

This is the first extensive molecular phylogeny for any group of Solanum in Australia. A total of 64 specimens representing 29 taxa were sampled, including 18 endemic Australian members of subgenus Leptostemonum (the “spiny solanums”) section Melongena sensu Symon. Data from the rDNA ITS region were analyzed using parsimony, maximum likelihood, and Bayesian methods to test the hypothesis that the dioecious and andromonoecious Australian species of section Melongena constitute a monophyletic group. Analyses showed support for the recognition of five clades among the Australian species of the section, but little support for the monophyly of the section itself. Australian dioecious Solanum species form two distinct clades and a number of enigmatic and previously unplaced dioecious taxa are here placed within a single clade. Three groups of andromonoecious species are also each monophyletic and are nested in a polytomy with three clusters of species from outside section Melongena. Furthermore, the phylogeny indicates that dioecy has evolved either once or twice in Australian Solanum, possibly from andromonoecious ancestry.

Studies of the genus Dicoma (Asteraceae, tribe Mutisieae s. 1.) indicate that this taxon as currently defined is paraphyletic, and in fact comprises at least three groups showing marked morphological and anatomical differences. One of these groups is differentiated from Dicoma s. str. by a large number of characters relating to the morphology and anatomy of the phyllaries, corolla, anthers, style, cypsela, and testa. This paper proposes that this group should be considered as a separate genus, for which the name Cloiselia S. Moore has nomenclatural priority. The article presents a systematic study of Cloiselia, which comprises four species: two are new (C. madagascariensis and C. humbertii) and one is a new combination (C. oleifolia).