One Antarctic slug to confuse them all: the underestimated diversity of Doris kerguelenensis.

• Published in: Invertebrate Systematics
• Main Authors: Maroni, Paige J., Baker, Bill J., Moran, Amy L., Woods, H. Arthur, Avila, Conxita, Johnstone, Glenn J., Stark, Jonathan S., Kocot, Kevin M., Lockhart, Susanne, Saucède, Thomas, Rouse, Greg W., Wilson, Nerida G.
• Other Authors: School of Biological Sciences Crawley, The University of Western Australia (UWA), Western Australian Museum (WAM), Department of Chemistry, University of South Florida, Tampa, FL, USA., University of South Florida Tampa (USF), University of Hawai'i Honolulu (UH), Division of Biological Sciences Missoula, MT, University of Montana, Department of Animal Biology (Institute for Research on Biodiversity (IRBio)), University of Barcelona, Australian Antarctic Division (AAD), Australian Government, Department of the Environment and Energy, Department of Biological Sciences, University of Alabama Tuscaloosa (UA), Department of Invertebrate Zoology and Geology, California Academy of Sciences, Biogéosciences UMR 6282 (BGS), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), Scripps Institution of Oceanography (SIO - UC San Diego), University of California San Diego (UC San Diego), University of California (UC)-University of California (UC), The work was supported by the Antarctic Circumnavigation Expedition (carried out by the Swiss Polar Institute, supported by the ACE Foundation and Ferring Pharmaceuticals), the French Polar Institute and LTSER ZATA (#1044), the US National Science Foundation (PLR-1341485, ANT-0551969 to A. L. Moran, ANT-0440577 to H. A. Woods, and DEB-1846174 to K. M. Kocot), BLUEBIO (CTM2016-78901/ANT), the Society of Australian Systematic Biologists (SASB), the University of Western Australia Oceans Institute (UWA-OI) Robson and Robertson award, the Malacological Society of Australasia (MSA) and the Antarctic Science Foundation (ASF). This work was also supported by ARC SRIEAS Grant SR200100005 Securing Antarctica's Environmental Future.
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2022
• Subjects: allopatry; Antarctica; Antarctic marine biodiversity; cryptic species; cytochrome oxidase I; direct development; mtDNA; nudibranch mollusc; phylogeny; refugia; species delimitation; [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics; Phylogenetics and taxonomy; Antarctic; Southern Ocean; The Antarctic; Antarc*
• Online Access: https://hal.science/hal-03718383; https://doi.org/10.1071/IS21073

17 pages International audience The Antarctic marine environment, although rich in life, is predicted to experience rapid and significant effects from climate change. Despite a revolution in the approaches used to document biodiversity, less than one percent of Antarctic marine invertebrates are represented by DNA barcodes and we are at risk of losing biodiversity before discovery. The ease of sequencing mitochondrial DNA barcodes has promoted this relatively ‘universal’ species identification system across most metazoan phyla and barcode datasets are currently readily used for exploring questions of species-level taxonomy. Here we present the most well-sampled phylogeny of the direct-developing, Southern Ocean nudibranch mollusc, Doris kerguelenensis to date. This study sampled over 1000 new Doris kerguelenensis specimens spanning the Southern Ocean and sequenced the mitochondrial COI gene. Results of a maximum likelihood phylogeny and multiple subsequent species delimitation analyses identified 27 new species in this complex (now 59 in total). Using rarefaction techniques, we infer more species are yet to be discovered. Some species were only collected from southern South America or the sub-Antarctic islands, while at least four species were found spanning the Polar Front. This is contrary to dispersal predictions for species without a larval stage such as Doris kerguelenensis. Our work demonstrates the value of increasing geographic scope in sampling and highlights what could be lost given the current global biodiversity crisis.