Antarctic and Sub-Antarctic Asteroidea database

Abstract The present dataset is a compilation of georeferenced occurrences of asteroids (Echinodermata: Asteroidea) in the Southern Ocean. Occurrence data south of 45°S latitude were mined from various sources together with information regarding the taxonomy, the sampling source and sampling sites when available. Records from 1872 to 2016 were thoroughly checked to ensure the quality of a dataset that reaches a total of 13,840 occurrences from 4,580 unique sampling events. Information regarding the reproductive strategy (brooders vs. broadcasters) of 63 species is also made available. This dataset represents the most exhaustive occurrence database on Antarctic and Sub-Antarctic asteroids.


Introduction
Mapping and understanding life diversity are major issues for the community of biologists and ecologists who focus on the Southern Ocean (SO). For several years, many initiatives such as the International Polar Year, the Census of Antarctic Marine Life (CAML 2005(CAML -2010, the Scientific Committee on Antarctic Research: Marine Biodiversity Information Network (SCAR MarBIN, www.biodiversity.aq) or the Biogeographic Atlas of the Southern Ocean ) have also gathered information from distinct and transversal scientific domains to provide new multidisciplinary insights in the study of the SO marine ecosystems, linking biogeographic, phylogeographic, physiological, oceanographic, and biogeochemistry data. Such programs have established the most exhaustive and accurate inventories of scientific data ever, since the first historical researches of James Cook in 1772-1775 in the region, and have provided open source information systems (e.g., Register of Antarctic Marine Species, De Broyer and Danis 2010; Global Biodiversity Information Facility, http:// www.gbif.org; Ocean Biogeographic Information System http://www.iobis.org/; Van de Putte et al. 2015, http://www.biodiversity.aq).
This extensive assessment was pursued by major improvements in methodologies and data analyses. Improvement of dataset completeness and resolution facilitates modelling approaches (Gutt et al. 2012) that provide interesting tools to better understand distribution patterns in this poorly documented part of the world.
Among benthic taxonomic groups, Asteroidea (Echinodermata) are well represented in the SO with 12% of the global species richness present in the region (Mah and Blake 2012). Around 300 species (Moreau et al. 2015) were reported at all depths including some potential keystone species in benthic communities (McClintock et al. 1988. As for many taxonomic groups, adaptations of invertebrates to the polar conditions of the SO environments have been widely reported (Peck 2002(Peck , 2016 and have led to unique biological traits and life-strategies as well as high levels of endemism in the region (Chown et al. 2015). In particular, reproductive strategies are diversified in the SO with a distinction between brooding and broadcasting species (Poulin et al. 2002;Pearse et al. 2009). In asteroids, the two distinct reproductive strategies strongly drive species distribution patterns and the biogeography of the class in the SO (Moreau et al. 2017).
The present dataset is a compilation of georeferenced occurrences, at species level, for the whole class Asteroidea in the SO. Records from 1872 to 2016 have been gathered from various open source databases. Data collected during recent and unpublished campaigns were also added including records from literature, reaching a total of 13,840 occurrences from 4,580 unique sampling events. This dataset represents the most exhaustive database on Antarctic and Sub-Antarctic asteroids. ence of gyres or the geographic distance among locations has also been emphasised. This dataset helped to better describe the different biogeographic patterns within asteroids, which are overall congruent with other taxa and differs according to species reproductive strategy. This suggests a differential influence of dispersal capabilities on species distribution patterns. Analyses at genus levels also revealed the underlying legacy of past oceanographic and geodynamic processes in present-day patterns such as the existence of a trans-Antarctic pathway that split the Antarctic continent into two entities in the past. The detailed results are available from Moreau et al. (2017).
Data description: Asteroids are common invertebrates of Antarctic benthic communities considering the relative high species richness of the group in the region with regards to the world total diversity ). They play a significant ecological role in Antarctic ecosystems, including in trophic networks (most species being predators) (Dayton 1972;Lawrence 2013). The present dataset, that focuses on regions located at latitudes higher than 45°S, compiles 28 families out of the 39 known worldwide (Mah 2017) with 13,840 occurrences gathered from various sources. The time coverage of the collection starts in 1872 with the HMS Challenger expedition and ends in 2016 with sampled collected during the RRS James Clark Ross JR15005 SO-AntEco cruise.
Associated to occurrence data, depth, relative position to the PF, taxonomic information and bioregion were implemented when available. Depth data were extracted from www.gebco.net. Information regarding the reproductive strategy (brooding or broadcasting) of 63 species out of the 299 described was included in the database. Corresponding bioregions of the observed occurrences were specified following Moreau et al. 2017 Quality control description: Data are available at species level. Nomenclature was thoroughly checked using the Taxon Match Tool implemented in the World Register of Marine Species (WoRMS Editorial Board 2016), to delete all potential discrepancies and update the taxonomy determination. All replicates originating from overlapping origins as well as errors regarding the georeferencing, species synonymy, or misspelling were removed. Most of the occurrences additions originating from recent campaigns were identified by Christopher Mah and Camille Moreau.

General taxonomic coverage description
The present dataset is the most exhaustive and up-to-date list of available occurrences for the class Asteroidea (Echinodermata), in the entire Southern Ocean. This collection provides information about the occurrence of 28 asteroid families, 118 genera, and 299 species. Occurrence distribution is illustrated on Figure 1.

Acknowledgements
This work was supported by a "Fonds pour la formation à la Recherche dans l'Industrie et l'Agriculture" (FRIA) grants to C. Moreau. C. Mah was funded by MNHN invited researcher grants (2013,2014,2015,2016). This is contribution no. 16 to the vERSO project (www.versoproject.be), funded by the Belgian Science Policy Office (BELSPO, contract n°BR/132/A1/vERSO). This is contribution to the IPEV programs n°1124 RE-VOLTA and n°1044 PROTEKER and to team SAMBA of the Biogeosciences laboratory. We are grateful to the crew and participants of all the cruises and research programs involved in the capture of the samples included in this dataset: POKER 2, REVOLTA 1 & 2, CEAMARC, JR144, JR179, JR230, JR262, JR275, JR287, JR15005. We also thank the following institutions: