Host specificity versus plasticity: testing the morphology-based taxonomy of the endoparasitic copepod family Splanchnotrophidae with COI barcoding

The Splanchnotrophidae is a family of highly modified endoparasitic copepods known to infest nudibranch or sacoglossan sea slug hosts. Most splanchnotrophid species appear to be specific to a single host, but some were reported from up to nine different host species. However, splanchnotrophid taxonomy thus far is based on external morphology, and taxonomic descriptions are, mostly, old and lack detail. They are usually based on few specimens, with intraspecific variability rarely reported. The present study used molecular data for the first time to test (1) the current taxonomic hypotheses, (2) the apparently strict host specificity of the genus Ismaila and (3) the low host specificity of the genus Splanchnotrophus with regard to the potential presence of cryptic species. Phylogenetic analyses herein used sequences of the barcoding region of the cytochrome oxidase I (COI) gene from 40 specimens representing 13 species of five genera. Species delimitation approaches include distance and barcoding gap analyses, haplotype networks and diagnostic nucleotides. Molecular results are largely compatible with the commonly accepted, morphology-based taxonomy of the Splanchnotrophidae. Strict host specificity could be confirmed for two Ismaila species. COI analyses also supported the idea that Splanchnotrophus angulatus is host-promiscuous. In Ismaila, morphology seems more suitable than barcoding to display speciation events via host switches in a recent Chilean radiation. In Splanchnotrophus, some genetic structure suggests ongoing diversification, which should be investigated further given the inadequate morphology-based taxonomy. The present study thus supports the presence of two different life history strategies in splanchnotrophids, which should be explored integratively

Geographic ranges of ascidians from Antarctica and the southeastern Pacific

Historical and novel data on the geographic and bathymetric distribution of ascidians from Antarctic, Magellan and Chilean waters are compiled, and an inventory of taxa comprising 162 species reported over a 150 year period from the Antarctic region South Polar Province (SPP) compiled. The ascidian fauna from the South Shetland Islands (SSI) is compared with that of the Magellan region, Patagonia and the Chilean coast. We collected 46 ascidian species along the Chilean coast, and during four expeditions to King George Island (SSI) by SCUBA between 2003–2012. About 15% of King George Island (SSI) species are observed to occur also in shallow waters of southern Chile (SCL). Few species known from warm temperate southeastern Pacific (Northern Chile, NCL) waters are absent from the Chilean part of the Magellan Province (SCL). With most data contributed from the Chilean coast coming from the SCL, and with limited sampling having been undertaken at depths exceeding 100 m in the NCL, apparent differences in species richness along the Chilean coast could be attributed to differential sampling effort. We detail 12 species from our Antarctic and Chilean collections in detail, including one, Diplosoma listerianum, not previously reported from Chilean waters, and the genus Botryllus, previously known from them on the basis of a single record

ReSurveyEurope : A database of resurveyed vegetation plots in Europe

Aims: We introduce ReSurveyEurope — a new data source of resurveyed vegetation plots in Europe, compiled by a collaborative network of vegetation scientists. We de- scribe the scope of this initiative, provide an overview of currently available data, governance, data contribution rules, and accessibility. In addition, we outline further steps, including potential research questions. Results: ReSurveyEurope includes resurveyed vegetation plots from all habitats. Version 1.0 of ReSurveyEurope contains 283,135 observations (i.e., individual sur- veys of each plot) from 79,190 plots sampled in 449 independent resurvey projects. Of these, 62,139 (78%) are permanent plots, that is, marked in situ, or located with GPS, which allow for high spatial accuracy in resurvey. The remaining 17,051 (22%) plots are from studies in which plots from the initial survey could not be exactly relocated. Four data sets, which together account for 28,470 (36%) plots, provide only presence/absence information on plant species, while the remaining 50,720 (64%) plots contain abundance information (e.g., percentage cover or cover–abun- dance classes such as variants of the Braun- Blanquet scale). The oldest plots were sampled in 1911 in the Swiss Alps, while most plots were sampled between 1950 and 2020. Conclusions: ReSurveyEurope is a new resource to address a wide range of re- search questions on fine-scale changes in European vegetation. The initiative is de- voted to an inclusive and transparent governance and data usage approach, based on slightly adapted rules of the well-established European Vegetation Archive (EVA). ReSurveyEurope data are ready for use, and proposals for analyses of the data set can be submitted at any time to the coordinators. Still, further data contributions are highly welcom

ReSurveyEurope: A database of resurveyed vegetation plots in Europe

Abstract Aims We introduce ReSurveyEurope — a new data source of resurveyed vegetation plots in Europe, compiled by a collaborative network of vegetation scientists. We describe the scope of this initiative, provide an overview of currently available data, governance, data contribution rules, and accessibility. In addition, we outline further steps, including potential research questions. Results ReSurveyEurope includes resurveyed vegetation plots from all habitats. Version 1.0 of ReSurveyEurope contains 283,135 observations (i.e., individual surveys of each plot) from 79,190 plots sampled in 449 independent resurvey projects. Of these, 62,139 (78%) are permanent plots, that is, marked in situ, or located with GPS, which allow for high spatial accuracy in resurvey. The remaining 17,051 (22%) plots are from studies in which plots from the initial survey could not be exactly relocated. Four data sets, which together account for 28,470 (36%) plots, provide only presence/absence information on plant species, while the remaining 50,720 (64%) plots contain abundance information (e.g., percentage cover or cover–abundance classes such as variants of the Braun‐Blanquet scale). The oldest plots were sampled in 1911 in the Swiss Alps, while most plots were sampled between 1950 and 2020. Conclusions ReSurveyEurope is a new resource to address a wide range of research questions on fine‐scale changes in European vegetation. The initiative is devoted to an inclusive and transparent governance and data usage approach, based on slightly adapted rules of the well‐established European Vegetation Archive (EVA). ReSurveyEurope data are ready for use, and proposals for analyses of the data set can be submitted at any time to the coordinators. Still, further data contributions are highly welcome

<scp>ReSurveyEurope</scp>: A database of resurveyed vegetation plots in Europe

AbstractAimsWe introduce ReSurveyEurope — a new data source of resurveyed vegetation plots in Europe, compiled by a collaborative network of vegetation scientists. We describe the scope of this initiative, provide an overview of currently available data, governance, data contribution rules, and accessibility. In addition, we outline further steps, including potential research questions.ResultsReSurveyEurope includes resurveyed vegetation plots from all habitats. Version 1.0 of ReSurveyEurope contains 283,135 observations (i.e., individual surveys of each plot) from 79,190 plots sampled in 449 independent resurvey projects. Of these, 62,139 (78%) are permanent plots, that is, marked in situ, or located with GPS, which allow for high spatial accuracy in resurvey. The remaining 17,051 (22%) plots are from studies in which plots from the initial survey could not be exactly relocated. Four data sets, which together account for 28,470 (36%) plots, provide only presence/absence information on plant species, while the remaining 50,720 (64%) plots contain abundance information (e.g., percentage cover or cover–abundance classes such as variants of the Braun‐Blanquet scale). The oldest plots were sampled in 1911 in the Swiss Alps, while most plots were sampled between 1950 and 2020.ConclusionsReSurveyEurope is a new resource to address a wide range of research questions on fine‐scale changes in European vegetation. The initiative is devoted to an inclusive and transparent governance and data usage approach, based on slightly adapted rules of the well‐established European Vegetation Archive (EVA). ReSurveyEurope data are ready for use, and proposals for analyses of the data set can be submitted at any time to the coordinators. Still, further data contributions are highly welcome.</jats:sec

Opercularella

&lt;i&gt;Opercularella&lt;/i&gt; sp. &lt;p&gt;(Fig. 2 D)&lt;/p&gt; &lt;p&gt; &lt;b&gt;Material examined&lt;/b&gt;. &lt;b&gt;Stn. RAS&lt;/b&gt; &mdash; 19.ii.2010, Ant.04/2010 (43 m): sterile colonies epizoic on &lt;i&gt;Antarctoscyphus spiralis&lt;/i&gt; (MHNG-INVE-79793); Ant.14/2010 (43 m): sterile colony on plumose bryozoan (MHNG-INVE-79789).&lt;/p&gt; &lt;p&gt; &lt;b&gt;Description&lt;/b&gt;. Hydrorhiza reptant, giving off pedicellate hydrothecae at irregular intervals. Pedicels slender (50&ndash;70 &micro;m wide) and of varied length (155&ndash;730 &micro;m), either unbranched or sparingly and irregularly branched once or twice; perisarc spirally grooved, slightly widening distally and merging smoothly into hydrotheca; pedicel and hydrotheca delimited by delicate &quot;diaphragm&quot;. Hydrothecae 360&ndash;560 &micro;m long, lateral walls slightly divergent, widest (110&ndash;160 &micro;m) at opercular base; operculum membranous, conical, pleated, not delimited basally by crease line. Gonothecae absent.&lt;/p&gt; &lt;p&gt; &lt;b&gt;Remarks&lt;/b&gt;. The sterile condition of the present material prevent us from providing a reliable identification for this species. It may belong to &lt;i&gt;Opercularella belgicae&lt;/i&gt; (Hartlaub, 1904), but hydrothecal pedicels of this species appear to be smooth, except for the presence of 2&ndash;3 basal, spiral annulations (see Galea 2007).&lt;/p&gt;Published as part of &lt;i&gt;Galea, Horia R. &amp; Schories, Dirk, 2012, Some hydrozoans (Cnidaria) from King George Island, Antarctica, pp. 1-21 in Zootaxa 3321&lt;/i&gt; on page 7, DOI: &lt;a href="http://zenodo.org/record/213236"&gt;10.5281/zenodo.213236&lt;/a&gt

Sertularella

&lt;i&gt;Sertularella&lt;/i&gt; sp. &lt;p&gt;(fig. 5K&ndash;P, table 5)&lt;/p&gt; &lt;p&gt; &lt;i&gt;Sertularella ellisi&lt;/i&gt; f. &lt;i&gt;lagenoides&lt;/i&gt; &mdash; Leloup, 1974: 28, fig. 22. [not &lt;i&gt;S. ellisii&lt;/i&gt; (Deshayes &amp; Milne-Edwards, 1836)]. &lt;i&gt;Sertularella peregrina&lt;/i&gt; &mdash; Leloup, 1974: 31, fig. 25 (not &lt;i&gt;S. peregrina&lt;/i&gt; Bale, 1926).&lt;/p&gt; &lt;p&gt; &lt;b&gt;Material examined&lt;/b&gt;. &lt;b&gt;Stn. RHO&lt;/b&gt; &mdash; 01.xi.2009, DS264 (15 m): several sterile stems, up to 1.4 cm high, on sponge substrate. &lt;b&gt;Stn. TIB&lt;/b&gt; &mdash; 01.xi.2009, DS166 (15 m): numerous sterile stems, up to 1.4 cm high, epizoic on sponge (MHNG-INVE-79629); DS207 (17 m): a single, sterile stem, 0.9 cm high, on sponge. &lt;b&gt;Stn. GNZ&lt;/b&gt; &mdash; 25.v.2007, S08 (10 m): several infertile stems, up to 1.4 cm high, on sponge. &lt;b&gt;Stn. CHN&lt;/b&gt; &mdash; 25.iv.2011, S10 (2 m): six infertile stems, 4&ndash;7 mm high.&lt;/p&gt; &lt;p&gt; &lt;b&gt;Description&lt;/b&gt;. Creeping, ramified, anastomosing stolon, giving rise to erect shoots up to 1.4 cm high; these unbranched or irregularly branched; divided into internodes of variable length by means of weak, oblique constrictions of perisarc; internodes collinear (fig.5L) or slightly zigzagging (fig. 5M). Each internode gradually widening from base to tip, bearing a hydrotheca distally. Side branches, when present, arising in front or rear side of stem, occasionally given off from within a stem hydrotheca (fig. 5N); structure similar to that of stem, though internode length may be comparatively short. Hydrothecae alternate, flask-shaped, slightly swollen basally, constricted below aperture; adcauline wall 2/5th adnate, free surface smooth or slightly wrinkled, abcauline wall slightly longer than free adcauline part; generally three internal perisarc cusps below the aperture: one abcauline and two latero-adcauline; hydrothecal margin with four triangular plates separated by rather shallow embayments. Gonothecae absent.&lt;/p&gt; &lt;p&gt; &lt;b&gt;Remarks&lt;/b&gt;. In sample DS166 (Stn. TIB), this species co-occurs with &lt;i&gt;Sertularella mixta&lt;/i&gt; sp. nov. (see above) on the same substrate, a sponge, and their size difference is striking, allowing rapid separation.&lt;/p&gt; &lt;p&gt;The pattern of branch formation in this species is peculiar for the genus: branches are given off not laterally, but in front or from rear side of the stem, perpendicular to it. The morphological variation within the available sample is illustrated in table 5. The development of intrathecal, submarginal cusps is variable, from absent, to slightly marked, to conspicuous, nearly reaching the center of hydrotheca. Hydrothecae in specimens from Stn. GNZ, S08 exhibit either 3 or 5 internal cusps (2 latero-adcauline, one abcauline, and, sometimes, 2 additional latero-abcauline), showing varied degrees of hypertrophy (fig. 5P).&lt;/p&gt; &lt;p&gt; Leloup's (1974) material assigned to both &lt;i&gt;S. ellisi&lt;/i&gt; f. &lt;i&gt;lagenoides&lt;/i&gt; and &lt;i&gt;S. peregrina&lt;/i&gt; may belong to either this species or &lt;i&gt;S. mixta&lt;/i&gt;, since no measurements allowing a reliable comparison were provided by this author. &lt;i&gt;Sertularella ellisii&lt;/i&gt; is an essentially Mediterranean-eastern Atlantic species (Ramil &lt;i&gt;et al&lt;/i&gt;. 1992), while &lt;i&gt;S. peregrina&lt;/i&gt; occurs in Australia (Bale 1926); it is unlikely that their occurrence extends to the southwestern Pacific. Additionally, both &lt;i&gt;S. ellisi&lt;/i&gt; and &lt;i&gt;S. peregrina&lt;/i&gt; have more fusiform hydrothecae, thus different from the more tubular ones of the Chilean species.&lt;/p&gt; &lt;p&gt; &lt;b&gt;Distribution in Chile&lt;/b&gt;. Recorded from Punta de Choros to Corral (present study).&lt;/p&gt; &lt;p&gt; &lt;b&gt;World records&lt;/b&gt;. Impossible to evaluate based on current knowledge.&lt;/p&gt;Published as part of &lt;i&gt;Galea, Horia R. &amp; Schories, Dirk, 2012, Some hydrozoans (Cnidaria) from Central Chile and the Strait of Magellan, pp. 19-67 in Zootaxa 3296&lt;/i&gt; on pages 45-46, DOI: &lt;a href="http://zenodo.org/record/280882"&gt;10.5281/zenodo.280882&lt;/a&gt

Oswaldella shetlandica Stepanjants 1979

&lt;i&gt;Oswaldella shetlandica&lt;/i&gt; Stepanjants, 1979 &lt;p&gt;(Fig. 3A&ndash;C)&lt;/p&gt; &lt;p&gt; &lt;i&gt;Oswaldella shetlandica&lt;/i&gt; &mdash; Pe&ntilde;a Cantero, Garc&iacute;a Carrascosa &amp; Vervoort, 1995: 342, fig. 1.&lt;/p&gt; &lt;p&gt; &lt;b&gt;Material examined&lt;/b&gt;. &lt;b&gt;Stn. ARD&lt;/b&gt; &mdash; 14.ii.2010, Ant.05/2010 (25 m): a bunch of sterile stems, &lt;i&gt;ca&lt;/i&gt;. 15 cm high; Ant.33/2011 (25 m): a profuse colony with stems up to 19 cm high, some bearing male gonothecae (MHNG-INVE- 79795). &lt;b&gt;Stn. RAS&lt;/b&gt; &mdash; 24.i.2011, Ant.25/2011 (30 m): a single, badly preserved, sterile stem, &lt;i&gt;ca&lt;/i&gt;. 4 cm high; Ant.28/ 2011 (30 m): a single, sterile cormoid, &lt;i&gt;ca&lt;/i&gt;. 6.5 cm high; 02.ii.2011, Ant.26/2011 (40 m): fragmentary colony, coming as three broken parts totaling &lt;i&gt;ca&lt;/i&gt;. 6 cm high; 11.ii.2010, Ant.01/2010 (30 m): colony composed of a bunch of stems, up to 12 cm high, with numerous male gonothecae (MHNG-INVE-79794).&lt;/p&gt; &lt;p&gt; &lt;b&gt;Remarks&lt;/b&gt;. For a description of this species and synonymy, see Pe&ntilde;a Cantero, Garc&iacute;a Carrascosa &amp; Vervoort (1995).&lt;/p&gt; &lt;p&gt; &lt;b&gt;Geographical distribution&lt;/b&gt;. Possibly endemic to West Antarctica (Pe&ntilde;a Cantero &amp; Vervoort 2004).&lt;/p&gt;Published as part of &lt;i&gt;Galea, Horia R. &amp; Schories, Dirk, 2012, Some hydrozoans (Cnidaria) from King George Island, Antarctica, pp. 1-21 in Zootaxa 3321&lt;/i&gt; on page 13, DOI: &lt;a href="http://zenodo.org/record/213236"&gt;10.5281/zenodo.213236&lt;/a&gt