DNA sequence data of hydromedusae and hydroids collected in the fjords near Bergen, Norway, permitted to connect three leptomedusae to three thecate hydroids with hitherto unknown life cycles. For all three species pairs, identical 16S and 18S sequences could be found. For comparisons, estimates of intraspecific variation of 16S sequences of other leptomedusa species were determined by comparing specimens collected at different localities. The sequence comparisons allowed us to conclude that Ptychogena croceaKramp & Dumas, 1925 is the medusa stage of the hydroid Stegopoma plicatile (M. Sars, 1863), Earleria quadrata (Hosia & Pages, 2007) the medusa of Racemoramus panicula (G.O. Sars, 1874), and Cyclocanna welshiBigelow, 1918 the medusa of Egmundella producta (G.O. Sars, 1874). Due to non-matching geographic distribution patterns of the medusa and hydroid phases, as well as the possibility that other related medusa species may have morphologically identical hydroids, the identities of Stegopoma plicatile and Racemoramus panicula are considered ambiguous. These nominal species likely refer to species complexes. Their names are therefore considered as partial synonyms of the medusa-based names and the latter should remain in use despite being more recent. Cyclocanna welshi and Egmundella producta are recognised as synonyms, and the species should from now on be referred to as Cyclocanna producta (G.O. Sars, 1874) n. comb.
INTRODUCTION
The life cycles of many hydromedusae and hydroids remain unknown because they are rare or difficult to cultivate. DNA barcodes, namely mitochondrial 16S and COI sequences, have recently emerged as a useful tool to unravel hydrozoan life cycles through matching sequences obtained from medusae and hydroids. Two recent papers have thus identified the polyp stage of Oceania armata Kölliker, 1853 (Schuchert, 2016b) and connected the polyp Boreohydra simplex Westblad, 1937 with the medusa Plotocnide borealis Wagner, 1885 (Pyataeva et al., 2016).
During the last decade, the authors have sampled hydroids and medusae in Norway, mostly in the fjords near Bergen. The specimens were used for various taxonomic and systematic research, including DNA based phylogenetics and constructing barcode databases for the molecular identification of hydrozoans. A recent sampling in the deep waters of Korsfjord and Raunefjord yielded three leptomedusa species whose 16S and 18S sequences matched those of polyp stages collected in the same region.
Here we present a synthesis of these results with a reevaluation of the life cycle and taxonomy of the three Leptothecata species.
MATERIAL AND METHODS
Thecate hydroids were collected on various substrates by dredging. Leptomedusae were collected from various depths and locations using plankton nets of different sizes (details on the new material are given in Appendix 1). For depths below 70 m, a modified WP3 plankton net with a non-filtering cod-end and 750 μm mesh size was used. For species identification we used Kramp (1959), Cornelius (1995) and other works mentioned in the Taxonomy part.
DNA extracts and 16S sequences were obtained as given in Schuchert (2005, 2016b). Most 18S sequences were determined as described in Leclère et al. (2009), except for three (marked with § in Appendix 1) which were retrieved by BlastN from transcriptome assemblies (L. Leclère, C. Dunn, and C. Munro, unpublished data). Alignments and phylogenetic analyses were performed as given in Schuchert (2005, 2016b). The aligned 16S sequences were trimmed to the position of the 3′ ends of the primers SHA/SHB which were used for this study (Cunningham & Buss, 1993). The aligned 18S sequences were trimmed to the shortest available sequence. Differences between sequence pairs were quantified using p-distances (uncorrected base-pair differences in %, Collins et al., 2012) using the software Bioedit (Hall, 1999).
In order to have a wider spectrum of species for comparisons, all suitable 16S sequences of leptomedusae (excluding Campanulariidae) found in the GenBank database were also included in the analyses (GenBank accession numbers can be taken from Figs 1–2). The Campanulariidae form a distinct, separate clade (Leclère et al., 2009; Maronna et al., 2016) and were excluded from our analysis as they do not contribute additional information. Additional sequencing of COI and 16S was carried out at the CCDB ( http://ccdb.ca/resources/) for some medusa specimens, with the sequences deposited in the BOLD database (Appendix 2). As these 16S sequences represented the same haplotypes as given in Appendix 1, they were not included in the final analysis in order to avoid dense, unreadable phylogenetic trees.
Abbreviations
BOLD
The Barcode of Life Data System (see Ratnasingham & Hebert, 2007), http://boldsystems.org
CCDB
Canadian Centre for DNA Barcoding
GenBank
Genetic sequence database of the National Institute of Health, USA, http://www.ncbi.nlm.nih.gov/genbank
MHNG
Muséum d'histoire naturelle de Genève, Switzerland
RESULTS AND DISCUSSION
Maximum likelihood analyses
16S and 18S sequence data were used to obtain Maximum Likelihood trees (Figs 1–2) which graphically visualise inter- and intraspecific sequence divergences. Comparing the length of the branches separating the samples allows rapid identification of identical or highly similar sequences found for polyp and medusa stages (Figs 1–2, highlighted in red), as well as the visualisation of the intraspecific distances seen in a few other species (highlighted in blue).
The mitochondrial 16S gene sequence tends to be a reliable marker for Hydrozoa (Miglietta et al., 2007, 2009, 2015; Schuchert, 2005, 2016b; Zhang et al., 2015), but for species-level relationships it is advisable to include also a nuclear marker in order to exclude misleading effects of past introgressions or hybridisations on the mitochondrial markers (e. g. like in Miller et al., 2012). We used the nuclear 18S gene sequence to complement the results obtained using the 16S data, as they were available from other studies for a good number of the species and samples used here. Although 18S is not an ideal barcoding marker due its relatively low interspecific variability, in the present data set the species were sufficiently well separated and the polyp-medusa matches were also seen in with the 18S sequences (Fig. 2, Table 2), thus adequately complementing the 16S results. Neither 16S nor 18S resolves satisfactorily the phylogenetic relationships at the family level. However, this was not the aim of this study and will be the subject of a forthcoming publication using more markers and taxa (L. Leclère, unpublished data).
16S and 18S intraspecific variation
The substitution rate of the mitochondrial 16S gene varies considerably within the Leptothecata subclades (Leclère et al., 2009; compare also Cunha et al., 2016 for COI). To quantify the extent of intraspecific variation within the leptomedusae, we calculated maximum p-distances for available pairs of conspecific specimens from different localities (Table 1). The observed values ranged from 0.34 to 1.18% and are lower than values observed for other hydrozoans [up to 4.4 % in Oceaniidae (Schuchert, 2016b); 5.5% in Corynidae (Schuchert, 2005); 19.6% in Plumularia setacea (Schuchert, 2014), but the Plumulariidae have a higher substitution rate (Leclère et al., 2009) and P. setacea could be a species complex]. For the 18S sequence only four preliminary estimates for the intraspecific divergences could be obtained (Table 2). These values allow evaluating sequence divergences other than perfect matches between polyp and medusa samples (Table 3).
Ptychogena crocea and Stegopoma plicatile
16S sequences obtained from three P. crocea medusae (Fig. 3) and two samples of the hydroid Stegopoma plicatile (Fig. 4), all collected in the vicinity of Bergen (Appendix 1), were identical. Likewise, also 18S and COI sequences were identical (COI: GenBank JN109191, BOLD specimens HYPNO_314 & HYPNO_286). These results indicate that the hydroid identified as Stegopoma plicatile is the polyp stage of P. crocea. In the 16S tree, its congener Ptychogena lactea appeared as a sister-species, although well separated from P. crocea. Other members of the Laodiceida clade (Maronna et al., 2016), such as Modeeria rotunda, clustered nearby.
Ptychogena crocea is a distinct and conspicuous medusa and easily identifiable. Its intensively orange-yellow manubrium and gonad pouches makes it very visible in plankton samples, even young stages (Fig. 3D). In addition to its yellow-orange colour, the characteristic lateral perradial stomach diverticula (gonad pouches, Fig. 3B) are very large and not attached to the subumbrella. Preserved material can nevertheless be confused with Modeeria rotunda (Quoy & Gaimard, 1827) and Chromatonema rubrum Fewkes, 1882, which also occur in deep waters of the North Atlantic (see Kramp, 1919, 1920, 1959; Russell, 1953; Edwards, 1973; Bleeker & van der Spoel, 1988; Cornelius, 1995; Schuchert, 2001; Pagès et al., 2006).
Fig. 1.
16S maximum likelihood phylogenetic tree of leptomedusan species obtained with PhyML (GTR+G+I model) and based on 605 bp positions of the mitochondrial 16S gene. Node-support values are bootstrap values of 100 pseudoreplicates (shown only if > 70%). For more details see text and Appendix 1.
Samples based on the polyp stage are indicated, all others are medusa samples. Highlighted in red are matching medusa and polyp stage samples. Highlighted in blue are samples used to estimate intraspecific variability (Table 1).
Fig. 2.
18S maximum likelihood phylogenetic tree of leptomedusan species obtained with PhyML (GTR+G+I model) and based on 1665 bp positions of the nuclear 18S gene. Node-support values are bootstrap values of 100 pseudoreplicates (shown only if > 70%). For more details see text and Appendix 1.
Samples based on the polyp stage are indicated, all others are medusa samples. Highlighted in red are matching medusa and polyp stage samples. Highlighted in blue are samples used to estimate intraspecific variability (Table 2).
Table 1.
Maximal observed intraspecific p-distance values (%) of 16S sequences of Leptothecata with a medusa stage.
Table 2.
Selected examples of maximal observed intraspecific p-distance values (%) of the 18S marker.
Table 3.
Observed minimal and maximal p-distances in %, for details of the used species and samples see Appendix 1.
Modeeria rotunda has a reddish-brown manubrium and characteristic interradial subumbrellar pockets giving the impression that the manubrium is partly sunken into the mesogloea.
Chromatonema rubrum has relatively small, white lateral gonad pouches and an orange to brown-reddish manubrium (Kramp, 1919, 1920). In addition, the cnidomes of the species differ: while P. crocea has 14–15 μm long microbasic mastigophores, C. rubrum and Modeeria rotunda have microbasic euryteles (19–20 μm and 25 μm; Russell, 1940).
The congener Ptychogena lactea A. Agassiz, 1865, which also occurs in the NE Atlantic, has gonads on thinner and more numerous lateral diverticula that are attached to the subumbrella. Their colour differs also from P. crocea, being white, or with a peachy or greenish tint. More details and illustrations of these two Ptychogena species will be presented in a forthcoming publication (P. Schuchert, unpublished data).
Fig. 3.
Ptychogena crocea Kramp & Dumas, 1925, living medusae, except C, from Korsfjord, Norway. (A) MHNG-INVE-94101, lateral view, bell diameter 23 mm height 14 mm. (B) Same specimen as in A, close up of gonads. (C) Same specimen as in A, nematocysts. (D) Younger individual, used to obtain DNA isolate 1163. (E) Same as D, close up of bell margin seen from oral side, showing tentacles, tentacle stumps and several cordyli.
Fig. 4.
Stegopoma plicatile (M. Sars, 1863), preserved sample MHNG-INVE-69614 (yielding DNA isolate 803) from Korsfjord, Norway, 650 m. (A) Whole colony. (B) Hydrotheca. (C) Branch with gonotheca (arrow).
Ptychogena crocea is a deep-water medusa with a rather restricted distribution and has so far been reported mostly along the Norwegian coast (Kramp & Dumas, 1925; Kramp, 1933, 1961; Rees, 1952; Hosia & Båmstedt, 2007), but there are also records of single specimens from the Cape Verde Islands and from the Gulf of Maine (Léon et al., 2007). However, these two records need to be confirmed by new samples as at least the one from the Cape Verde had an atypical colour and could have been Chromatonema rubrum.
In contrast, the hydroid Stegopoma plicatile has a very wide, circumglobal distribution (Vervoort, 1972; Edwards, 1973; Cornelius, 1995; Calder, 2012). It is widespread in the Arctic and reaches as far south as Sweden and into deep waters off Brittany. It has also been reported in Boreal and Arctic regions of the Pacific and scattered points in the Southern Hemisphere and Antarctica. The type material came from Norway. Although the species has been described repeatedly, the reproduction of S. plicatile remained unknown for a long time until Schuchert (2001) reported for the first time that it releases a medusa. This was also observed for one of the current samples (MHNG-INVE-69614) which produced medusae of about 2 mm in diameter with four perradial tentacles, small interradial bulbs and 1–3 cordyli per quadrant. There were no ocelli or statocysts present. The stomach was distinctly cruciform in cross-section and lacked the yellow colour. Unfortunately, it was not possible to cultivate the medusae for more than two days.
We can conclude from our sequence analyses that the hydroid from the vicinity of Bergen identified as Stegopoma plicatile is the polyp stage of Ptychogena crocea. The taxonomic consequences, however, are more difficult to assess. The markedly different distribution patterns of the endemic, medusa-based species Ptychogena crocea and the widely distributed polyp-based Stegopoma plicatile strongly suggest that the latter is most probably a complex of cryptic species. The morphology of the Stegopoma hydroids is rather simple and poor in diagnostic features (see Cornelius 1995; Schuchert, 2001), and it is likely that other medusae related to Ptychogena crocea might have nearly identical hydroids. Several Leptothecata are known to have indistinguishable or very similar hydroid stages, but distinct medusae [e. g. “Cuspidella”-type hydroids producing medusae of the genera Cosmetira Forbes, 1848 or Mitrocomella Haeckel, 1879, “Campanulina”type hydroids giving rise to medusae of the genera Eucheilota McCrady, 1859 and Eutonina Hartlaub, 1897 (Cornelius, 1995)].
The related medusa Modeeria rotunda has polyps with hydrothecae identical to those of Stegopoma plicatile, but with a colony that remains stolonal according to our current knowledge (Edwards, 1973; Cornelius, 1995; Schuchert, 2001). In the northern Atlantic Ocean, there are two further related medusa species with unknown polyp stages that potentially have a Stegopoma-like polyp stage: Ptychogena lactea and Chromatonema rubrum. Naumov (1969) attributed a “Cuspidella”-like hydroid (Bouillon et al., 2006) to Ptychogena lactea because he found them to have a similar distribution in the Arctic Sea. This is, however, not a convincing argument and the polyp of P. lactea must be considered unknown. Ptychogena lactea is primarily an Arctic species and the distribution of Stegopoma plicatile (Schuchert, 2001) also matches its occurrence. The morphologically similar Chromatonema rubrum is a rare oceanic medusa, but has a much wider distribution (Kramp, 1919, 1959; Bleeker & van der Spoel, 1988). It occurs in deep waters (406–1750 m; Bleeker & van der Spoel, 1988). To our knowledge, the medusa has not been found in coastal waters of Norway, but only far off the continent (Kramp, 1919; Fraser, 1974; Bleeker & van der Spoel, 1988; Licandro et al., 2015). Even if the discussed two medusae do not occur in coastal waters of Norway, they remain candidates for having a Stegopoma-like hydroid. So do the other Ptychogena medusae known from outside the region of the NE Atlantic: P. antarctica Browne, 1907, P. californica Torrey, 1909, and P. hyperborea Kramp, 1942.
When describing Stegopoma plicatile, Sars (1863) had material from four localities reaching from near Bergen, through Tromsø, to the northern tip of Norway in the Barents Sea. To our knowledge, no lectotype has been selected, and thus a more precise type locality cannot be given. Stegopoma plicatile was also designated by Totton (1930) as the type species of the genus.
While it is clear that Ptychogena crocea medusae are produced by hydroids referable to Stegopoma plicatile, it is still possible that even the type material of the latter was composed of several species. We therefore refrain from fully synonymising the two names and applying the senior name Stegopoma plicatile to the medusa Ptychogena crocea or suggesting a new combination of the two names. Synonymising the two names would lead to a confusing situation in which an endemic medusa has the name of a circumglobally distributed hydroid and which is likely a species complex. In the synonymy given below, Stegopoma plicatile is thus taxonomically only considered as a partial synonym. A similar situation was found for the medusa treated in the following.
Earleria quadrata and Racemoramus panicula
Earleria quadrata medusae (Fig. 5, GenBank number KY363957) and a Racemoramus panicula hydroid (GenBank FJ550511) from the same region proved to have identical 16S (Fig. 1) and 18S sequences (Fig. 2; KY363982, KY3639731). Several medusae of Earleria quadrata could be examined and they showed low 16S sequence variation of up to 2 bp differences per about 590 bp total length (Fig. 1, Table 3). This is compatible with intraspecific variation observed in other leptomedusan species (Table 1). Interestingly, three 16S sequences derived from Racemoramus panicula from the Gulf of Cadiz and the Alboran Sea (identified by C. Moura, JN714648 through JN714650) were very similar to the Norwegian samples, one of them (JN714648) even identical to both the medusa Earleria quadrata (KY363957) and the hydroid derived sequence (FJ550511).
Earleria quadrata is unmistakable among Norwegian leptomedusae due to its intensively deep-purple pigmented manubrium with white lips (Fig. 5). The numerous open statocysts (1–3 between each of the up to 40 tentacles) with 6 or more concretions in a single row are also rather characteristic. Earleria quadrata is endemic to the coastal waters of Norway and the genus currently comprises six species (Schuchert, 2017). The polyp stage was hitherto only known for the Californian Earleria corachloeae Widmer, Cailliet & Geller, 2010.
Fig. 5.
Earleria quadrata (Hosia & Pages, 2007), living medusa from Korsfjord, one individual in a catch of four used to obtain DNA isolate 1162.
While Earleria quadrata is only known very locally from deep waters of the Korsfjord south of Bergen (Hosia & Pages, 2007), the hydroid Racemoramus panicula has a very wide distribution. It occurs circumglobally in temperate to tropical regions, at depths of 20–5200 m (Schuchert, 2001; Calder, 2012). This extensive range made Calder (2012) doubt whether the observations represent a single species, prompting him to exclude records from the Pacific Ocean and attribute them to R. denticulata (Clarke, 1907), a species which so far had often been regarded as conspecific with R. panicula. The type locality of R. panicula is the Oslofjord (Norway) in a depth of 91–110 m (G. Sars, 1874).
Among the Campanulinidae, Racemoramus has a quite unique colony structure, consisting of an unbranched stem from which groups of “Campanulina”-like hydrothecae originate at intervals (Fig. 6 and Cornelius, 1995; Schuchert, 2001; Calder, 2012). Calder (2012) therefore proposed to keep it distinct from the genera Campanulina van Beneden, 1847 and Opercularella Hincks, 1868. No life cycle of any Racemoramus species is known so far, although Rees & Rowe (1969) found that Racemoramus panicula from Sweden releases a medusa. Earleria corachloeae, the only hitherto known hydroid of the genus Earleria, has branched colonies that correspond with the traditional diagnosis of the genus Campanulina van Beneden, 1847 as proposed by Bouillon et al. (2006).
Fig. 6.
Racemoramus panicula (G. O. Sars, 1874), sample MHNG-INVE-48748 from Korsfjord after DNA extraction, schematic drawing of part of main stem and some side-branches (some broken off).
While it is very probable that Sars' material of Racemoramus panicula is the polyp stage of Earleria quadrata and the latter is thus a junior synonym, the hydroid Racemoramus panicula as used today - even in the restricted sense of Calder (2012) - is most likely a species complex. The disparate distributions of the medusa and the hydroid stage support this hypothesis. Therefore, we prefer to conclude more precisely that the medusa of Earleria quadrata has a polyp stage that corresponds to the morphology of Racemoramus panicula, but that both names are better not fully synonymised until a world-wide molecular genetic study of Racemoramus permits delimiting the different populations and their distributions. We should thus continue to use the name of the medusa for this species for the time being.
As mentioned above, polyps of Racemoramus panicula from the Gulf of Cadiz and the Mediterranean had 16S sequences which were identical or very similar to the Norwegian medusa E. quadrata. This extends the likely distributional range of this medusa close to that of the morphologically similar Mediterranean medusa Earleria antoniae (Gili et al., 1998). It is therefore advisable to molecularly assess the species status of these two Earleria species to exclude the possibility of them representing morphologically divergent populations of the same species.
The taxonomic consequences at the family level are discussed in the next section.
Cyclocanna welshi and Egmundella producta
The two available samples of the medusa Cyclocanna welshi yielded 16S haplotypes differing only in one bp position. One of them was identical to the 16S obtained from the sample of Egmundella producta polyp described and figured by Schuchert (2016a). Likewise, the two 18S sequences were identical for polyp and medusa.
Cyclocanna welshi is a highly distinctive medusa. Its four radial canals and the gonads along them make a sharp bend shortly before reaching the circular canal and continue running along the circular canal before giving into it, resulting in a pattern reminiscent of a swastika (Fig. 7). Moreover, there are two types of tentacles: four large perradial tentacles with large bulbs situated at the marginal ends of the radial canals, and many short, papilliform tentacles between these. There are eight open statocysts, each with a linear array of concretions. The genus is monospecific. The collected samples were all reliably identifiable, but deteriorated rapidly so that no satisfactory photos could be made. The specimens appeared to be less pigmented than otherwise described (Bigelow, 1918; Kramp, 1926), but this is likely due to them being smaller (younger) stages.
Cyclocanna welshi is a rare medusa known from a few specimens only (Kramp, 1926, 1961; Cornelius, 1995). It occurs in cool, deep waters of the North Atlantic. The type locality is off Virginia, USA, in 0–140 m depth. The polyp Egmundella producta, formerly known as Lovenella producta, has been redescribed and revised recently (Schuchert, 2016a). It is also rather rare, but its known distribution in the Atlantic matches that of C. welshi. Records from the Pacific Ocean (Fraser, 1937) must either be referred to Egmundella gracilis Stechow, 1921 or another, as of yet unnamed species (Schuchert, 2016a).
Fig 7.
Cyclocanna welshi, lateral view, width about 10 mm, living medusa one day after capture, the bell is inverted and has shrunken considerably as it is usual for sensitive hydromedusae. Details: go = gonad, ma = manubrium, rt = short type of tentacle, st = statocyst, tb = bulb of large tentacle type.
The matching distributions of both medusa and hydroid permit synonymizing the names. The new name must thus be Cyclocanna producta (G.O. Sars, 1874) n. comb., as Sars' species name is older. The genus Egmundella Stechow, 1921 cannot be synonymised with Cyclocanna Bigelow, 1918, as the type species of Egmundella is Egmundella gracilis Stechow, 1921 and its life cycle – as well as that of any other congener – remains unknown. All the other Egmundella species must thus remain in this genus until more is known about their medusae or gonophores.
Kramp (1933) placed Cyclocanna welshi in the family Mitrocomidae Haeckel, 1879 and subsequent authors continued to do so, primarily on account of the open statocysts and the absence of ocelli or cirri. According to the diagnosis given in Bouillon et al. (2006), the hydroids of this family are of the “Cuspidella”-type. With the identification of the hydroid of Cyclocanna as an “Egmundella”-type, the family diagnosis clearly needs a revision. The genus Earleria is also currently placed in the Mitrocomidae (Arai & Brinckmann-Voss, 1980; Bouillon et al., 2006; as Foersteria Arai & Brinckmann-Voss, 1980). The “Campanulina”-like hydrothecae of Earleria corachloeae and the “Racemoramus”-like polyp in Earleria quadrata add a further argument for the need of a comprehensive revision of the Mitrocomidae and many other related families of Statocysta (Leclère et al., 2009). Such a revision is, however, beyond the scope of the present paper and must be based on a solid, comprehensive molecular phylogeny.
TAXONOMY
Order Leptothecata
Family Laodiceidae Agassiz, 1862
Genus
Ptychogena
A. Agassiz, 1865
Ptychogena A. Agassiz, 1865: 137, type species Ptychogena lactea A. Agassiz, 1865 by monotypy.
in part Stegopoma Levinsen, 1893: 177, type species Lafoea plicatilis M. Sars, 1863 (Totton, 1930).
Ptychogena crocea
Kramp & Dumas, 1925
Figs 3–4
Ptychogona crocea Kramp & Dumas, 1925: 290, pl. 1 figs 1–7. - Kramp, 1933: 558, fig. 21. - Russell, 1940: 519, figs 18–19, nematocysts. – Rees, 1952: 8, record Bergen, Norway. – Kramp, 1959: 137, fig. 158. – Kramp, 1961: 146. - Hosia & Båmstedt, 2007: 116, records Norway, Kors- and Fanafjord.
? Ptychogona crocea. - Léon et al., 2007: 57, record Cape Verde Islands.
in part Lafoea plicatilis M. Sars, 1863: 31.
? in part Stegopoma plicatile. – Kramp, 1913: 15, figs 1–2. – Broch, 1918: 26, fig. 8. – Edwards, 1973: 590. – Cornelius, 1995: 114, fig. 25. – Schuchert, 2001: 51, fig. 37A-E.
Type locality: Norway, Romsdal, deep waters of Moldefjord.
References: For the medusa Kramp & Dumas (1925), for the hydroid Cornelius (1995) and Schuchert (2001).
Family Mitrocomidae Haeckel, 1879
Genus
Earleria
Collins
et al.
, 2006
Foersteria Arai & Brinckmann-Voss, 1980: 88, type species Halistaura bruuni Navas, 1969 by original designation, invalid junior homonym of Foersteria Szépligeti [Insecta] (Collins et al., 2006).
Earleria Collins et al., 2006: 125, replacement name.
References: Arai & Brinckmann-Voss (1980); Bouillon et al. (2006); Collins et al. (2006).
Earleria quadrata
(Hosia & Pages, 2007)
Figs 5-6
Foersteria quadrata Hosia & Pages, 2007: 180, fig. 5.
in part Campanulina panicula G. O. Sars, 1874: 121, pl. 5 figs 9–13.
? Campanulina panicula. - Kramp, 1941: 1, figs 1–5. – Cornelius, 1995: 190, fig. 43. – Schuchert, 2001: 56, fig. 41, Iceland.
? not Opercularella panicula. – Vervoort, 1966: 104, figs 4–5. – Vervoort, 1972: 40, fig. 11a, Nicaragua (Pacific), Peru. – Leloup, 1974: 4, fig. 3
? Racemoramus panicula. – Calder, 2012: 26, fig. 24.
not Campanulina panicula. – Schuchert, 2003: 150, fig. 10, Indonesia.
Type locality: Korsfjorden, 25 km south of Bergen, Norway, > 500 m deep.
References: For the medusa see Hosia & Pages (2007), for the hydroid see Cornelius (1995), Schuchert (2001), or Calder (2012).
Genus Cyclocanna Bigelow, 1918
Cyclocanna Bigelow, 1918: 383, type species Cyclocanna welshi Bigelow, 1918 by monotypy.
Cyclocanna producta
(G.O. Sars, 1874) n. comb.
Fig. 7
Cyclocanna welshi Bigelow, 1918: 384, pl. 3 figs 2–5. - Kramp, 1926: 245, fig. 1. – Kramp, 1933: 571, fig. 35. – Kramp, 1959: 144, fig. 177. – Kramp, 1961: 152. – Cornelius, 1995: 134, fig. 29.
Calycella producta G.O. Sars, 1874: 118, pl. 5 figs 6–8. - Hincks, 1874: 134. - Verrill, 1879: 17. - Storm, 1879: 26. - Broch, 1907: 7.
Lovenella producta. - Segerstedt, 1889: 12. - Jäderholm, 1909: 79. - Kramp, 1935: 140, fig. 57E. - Fraser, 1944: 175, pl. 31 fig. 149. - Schuchert, 2000: 423. - Schuchert, 2001: 54, fig. 39.
Campanulina producta. - Bonnevie, 1899: 73. - Bonnevie, 1901: 10. - Broch, 1903: table. - Stechow, 1922: 146.
not Lovenella producta. - Fraser, 1911: 44, pl. 3 figs 7–10. - Fraser, 1914: 159, pl. 18 fig. 64. [in part Egmundella gracilis Stechow, 1921]
not Lovenella producta. - Fraser, 1937: 96, pl. 19 fig. 102.
? Opercularella producta. - Vervoort, 1966: 111, fig. 12a. - Vervoort, 1985: 279.
Egmundella producta. - Schuchert, 2016a: 219, figs 1A-D, 2A-C, 3A-F.
Type localities: The syntypes of Egmundella producta came from Bodø and the Lofoten (Norway). The type locality of Cyclocanna welshi is in the North-West Atlantic, off Viriginia, USA, 37.4705°N 74.4214°W, 0–140 m.
References: For the medusa see Cornelius (1995), for the hydroid see Schuchert (2016).
ACKNOWLEDGMENTS
The authors thank the sailors of the Observatoire Océanologique de Villefranche-sur-mer, the Station Biologique de Roscoff, the crew of RV Hans Brattström for their help in collecting polyps and medusae, and the staff at the Espegrend Marine Biological Station for providing facilities. We are grateful to Casey Dunn and Catriona Munro for providing the RNAseq data, which were used to retrieve some of the 18S sequences. Mrs J. Pralong kindly helped us with the sequencing of the samples. LL was supported by a grant from the Agence National de la Recherche (MEDUSEVO ANR-13PDOC-0016); AH by the Norwegian Taxonony Initiative (NTI, project no. 70184233/HYPNO) and ForBio Research School funding from the Research Council of Norway (project no. 248799) and the NTI (project no. 70184215).
REFERENCES
Michael Sars“ in den Jahren 1900–1902 in dem Nordmeer gesammelten Hydroiden.
Bergens Museum Aarbog (1903) 9(3): 1–14, pls 1–4, table. Google Scholar
Appendices
Appendix 1:
Specimens and Genbank accession numbers of new sequences (numbers starting with KY) used in this study. Details of the other sequences taken from GenBank and used in Figures 1 and 2 can be found by a GenBank search using the respective accession number. The 18S sequences marked with § were obtained from transcriptome assemblies.
