Systematics, phylogeography and historical biogeography of Eusiroidea (Crustacea, Amphipoda) from the Southern Ocean, with a special focus on the families Epimeriidae and Iphimediidae

The physical isolation of the Antarctic shelf and extreme life conditions contribute to its high degree of endemism. The shelf fauna would, however, be composed of Gondwanan descendants, but also of more recent colonizers. Extreme temperature changes along the climatic history of this region led to the extinction of some lineages, while others flourished. Using molecular phylogenetic methods, this thesis aims to contribute to the general understanding of the evolutionary processes — extinctions, dispersals and in situ diversifications — shaping the biodiversity and geographical distributions of Antarctic amphipods of the families Epimeriidae (genus Epimeria) and Iphimediidae. The systematics of the superfamily presumably including the latter two model families, Eusiroidea, is first revised. Secondly, species boundaries within Epimeria are investigated by using a combination of DNA-based species delimitation methods and morphological descriptions, to ultimately reassess the geographical distribution of species. Finally, the origin of Antarctic lineages, dispersals in/out of the Antarctic shelf and in situ diversification patterns of both Epimeria and iphimediids are explored, using time-calibrated phylogenies. The systematic study of Eusiroidea indicates that at least species belonging to 14 families, including Epimeriidae and Iphimediidae, should be included in a phylogenetically meaningful delimitation of the superfamily. The species richness within Epimeria is greatly underestimated as most nominal species appear to be complexes of geographically-restricted pseudocryptic species. The monophyly of Antarctic Epimeria and (sub-)Antarctic iphimediids suggests that both lineages evolved in isolation since their origin. Both latter clades likely arose from late Gondwanan ancestors and diversified in a cooling environment.En raison de l’isolement physique et des conditions environnementales extrêmes du plateau continental antarctique, la faune marine benthique de cette région présente de hauts degrés d’endémisme. Elle serait composée à la fois de descendants d’ancêtres gondwaniens, mais également de colonisateurs plus récents. Les changements extrêmes de température tout au long de l’histoire climatique de la région antarctique ont mené à l’extinction de certaines lignées, tandis que d’autres ont pu s’adapter aux nouvelles conditions et se diversifier. Par l’utilisation de méthodes de phylogénie moléculaire, cette thèse de doctorat vise à contribuer à la compréhension globale des processus évolutifs — extinctions, dispersions et diversifications in situ — qui ont façonné la biodiversité et les distributions géographiques actuelles de deux familles d’amphipodes, les Epimeriidae (genre Epimeria) et Iphimediidae. Dans un premier temps, la systématique de la superfamille incluant potentiellement ces deux familles modèles, Eusiroidea, est révisée. Ensuite, la diversité spécifique au sein du genre Epimeria est réévaluée par une combinaison de méthodes de délimitation d’espèces basées sur l’ADN et de descriptions morphologiques, pour ensuite redéfinir les distributions géographique des espèces. Finalement, l’origine des lignées antarctiques, d’éventuelles dispersions dans et en dehors d’Antarctique et les patterns de diversifications in situ au sein des deux familles modèles sont inférés sur base de phylogénies calibrées dans le temps. L’étude systématique des Eusiroidea démontre que des espèces appartenant à au moins 14 familles différentes, y compris les Epimeriidae et Iphimediidae, devraient être inclues dans une superfamille monophylétique. Cette étude démontre que la richesse spécifique au sein d’Epimeria est largement sous-estimée. En effet, la plupart des espèces nominales seraient en réalité des complexes d’espèces pseudocryptiques à distribution géographique restreinte. La monophylie des Epimeria antarctiques d’une part, et des Iphimediidae (sub-)antarctiques d’autre part, suggère que ces deux lignées ont évolué en isolement depuis leur origine. Elles descendraient directement d’ancêtres gondwaniens et n’auraient donc pas colonisé la région antarctique après sa séparation des autres fragments du Gondwana. De plus, la diversification initiale de ces deux clades serait liée au refroidissement progressif de la région antarctique

Systematics, phylogeography and historical biogeography of Eusiroidea (Crustacea, Amphipoda) from the Southern Ocean, with a special focus on the families Epimeriidae and Iphimediidae

The physical isolation of the Antarctic shelf and extreme life conditions contribute to its high degree of endemism. The shelf fauna would, however, be composed of Gondwanan descendants, but also of more recent colonizers. Extreme temperature changes along the climatic history of this region led to the extinction of some lineages, while others flourished. Using molecular phylogenetic methods, this thesis aims to contribute to the general understanding of the evolutionary processes — extinctions, dispersals and in situ diversifications — shaping the biodiversity and geographical distributions of Antarctic amphipods of the families Epimeriidae (genus Epimeria) and Iphimediidae. The systematics of the superfamily presumably including the latter two model families, Eusiroidea, is first revised. Secondly, species boundaries within Epimeria are investigated by using a combination of DNA-based species delimitation methods and morphological descriptions, to ultimately reassess the geographical distribution of species. Finally, the origin of Antarctic lineages, dispersals in/out of the Antarctic shelf and in situ diversification patterns of both Epimeria and iphimediids are explored, using time-calibrated phylogenies. The systematic study of Eusiroidea indicates that at least species belonging to 14 families, including Epimeriidae and Iphimediidae, should be included in a phylogenetically meaningful delimitation of the superfamily. The species richness within Epimeria is greatly underestimated as most nominal species appear to be complexes of geographically-restricted pseudocryptic species. The monophyly of Antarctic Epimeria and (sub-)Antarctic iphimediids suggests that both lineages evolved in isolation since their origin. Both latter clades likely arose from late Gondwanan ancestors and diversified in a cooling environment.(SC - Sciences) -- UCL, 201

<i>Epimeria</i> of the Southern Ocean with notes on their relatives (Crustacea, Amphipoda, Eusiroidea)

The present monograph includes general systematic considerations on the family Epimeriidae, a revision of the genus Epimeria Costa in Hope, 1851 in the Southern Ocean, and a shorter account on putatively related eusiroid taxa occurring in Antarctic and sub-Antarctic seas. The former epimeriid genera Actinacanthus Stebbing, 1888 and Paramphithoe Bruzelius, 1859 are transferred to other families, respectively to the Acanthonotozomellidae Coleman &amp; J.L. Barnard, 1991 and the herein re-established Paramphithoidae G.O. Sars, 1883, so that only Epimeria and Uschakoviella Gurjanova, 1955 are retained within the Epimeriidae Boeck, 1871. The genera Apherusa Walker, 1891 and Halirages Boeck, 1891, which are phylogenetically close to Paramphithoe, are also transferred to the Paramphithoidae. The validity of the suborder Senticaudata Lowry &amp; Myers, 2013, which conflicts with traditional and recent concepts of Eusiroidea Stebbing, 1888, is questioned. Eight subgenera are recognized for Antarctic and sub-Antarctic species of the genus Epimeria: Drakepimeria subgen. nov., Epimeriella K.H. Barnard, 1930, Hoplepimeria subgen. nov., Laevepimeria subgen. nov., Metepimeria Schellenberg, 1931, Pseudepimeria Chevreux, 1912, Subepimeria Bellan-Santini, 1972 and Urepimeria subgen. nov. The type subgenus Epimeria, as currently defined, does not occur in the Southern Ocean. Drakepimeria species are superficially similar to the type species of the genus Epimeria: E. cornigera (Fabricius, 1779), but they are phylogenetically unrelated and substantial morphological differences are obvious at a finer level. Twenty-seven new Antarctic Epimeria species are described herein: Epimeria (Drakepimeria) acanthochelon subgen. et sp. nov., E. (D.) anguloce subgen. et sp. nov., E. (D.) colemani subgen. et sp. nov., E. (D.) corbariae subgen. et sp. nov., E. (D.)  cyrano subgen. et sp. nov., E. (D.) havermansiana subgen. et sp. nov., E. (D.) leukhoplites subgen. et sp. nov., E. (D.) loerzae subgen. et sp. nov., E. (D.) pandora subgen. et sp. nov., E. (D.) pyrodrakon subgen. et sp. nov., E. (D.) robertiana subgen. et sp. nov., Epimeria (Epimeriella) atalanta sp. nov., Epimeria (Hoplepimeria) cyphorachis subgen. et sp. nov., E. (H.) gargantua subgen. et sp. nov., E. (H.) linseae subgen. et sp. nov., E. (H.) quasimodo subgen. et sp. nov., E. (H.) xesta subgen. et sp. nov., Epimeria (Laevepimeria) anodon subgen. et sp. nov., E. (L.) cinderella subgen. et sp. nov., Epimeria (Pseudepimeria) amoenitas sp. nov., E. (P.) callista sp. nov., E. (P.) debroyeri sp. nov., E. (P.) kharieis sp. nov., Epimeria (Subepimeria) adeliae sp. nov., E. (S.) iota sp. nov., E. (S.) teres sp. nov. and E. (S.) urvillei sp. nov. The type specimens of E. (D.) macrodonta Walker, 1906, E. (D.) similis Chevreux, 1912, E. (H.) georgiana Schellenberg, 1931 and E. (H.) inermis Walker, 1903 are re-described and illustrated. Besides the monographic treatment of Epimeriidae from the Southern Ocean, a brief overview and identification keys are given for their putative and potential relatives from the same ocean, i.e., the Antarctic and sub-Antarctic members of the following eusiroid families: Acanthonotozomellidae Coleman &amp; J.L. Barnard, 1991, Dikwidae Coleman &amp; J.L. Barnard, 1991, Stilipedidae Holmes, 1908 and Vicmusiidae Just, 1990. This overview revealed the existence of a new large and characteristic species of Alexandrella Chevreux, 1911, A. chione sp. nov. but also shows that the taxonomy of that genus remains poorly known and that several ‘variable widespread eurybathic species’ probably are species complexes. Furthermore, the genera Bathypanoploea Schellenberg, 1939 and Astyroides Birstein &amp; Vinogradova, 1960 are considered to be junior synonyms of Alexandrella. Alexandrella mixta Nicholls, 1938 and A. pulchra Ren in Ren &amp; Huang, 1991 are re-established herein, as valid species. It is pointed out that this insufficient taxonomic knowledge of Antarctic amphipods impedes ecological and biogeographical studies requiring precise identifications. Stacking photography was used for the first time to provide iconographic support in amphipod taxonomy, and proves to be a rapid and efficient illustration method for large tridimensionally geometric species. A combined morphological and molecular approach was used whenever possible for distinguishing Epimeria species, which were often very similar (albeit never truly cryptic) and sometimes exhibited allometric and individual variations. However in several cases, taxa were characterized by morphology only, whenever the specimens available for study were inappropriately fixed or when no sequences could be obtained. A large number of Epimeria species, formerly considered as eurybathic and widely distributed, proved to be complexes of species, with a narrower (overlapping or not) distribution. The distributional range of Antarctic Epimeria is very variable from species to species. Current knowledge indicates that some species from the Scotia Arc and the tip of the Antarctic Peninsula are narrow range endemics, sometimes confined to one island, archipelago, or ridge (South Georgia, South Orkney Islands, Elephant Island or Bruce Ridge); other species have a distribution encompassing a broader region, such as the eastern shelf of the Weddell Sea, or extending from the eastern shelf of the Weddell Sea to Adélie Coast. The most widely distributed species are E. (D.) colemani subgen. et sp. nov., E. (E.) macronyx (Walker, 1906), E. (H.) inermis Walker, 1903 and E. (L.) walkeri (K.H. Barnard, 1930), which have been recorded from the Antarctic Peninsula/South Shetland Islands area to the western Ross Sea. Since restricted distributions are common among Antarctic and sub-Antarctic Epimeria, additional new species might be expected in areas such as the Kerguelen Plateau, eastern Ross Sea, Amundsen Sea and the Bellingshausen Sea or isolated seamounts and ridges, where there are currently no Epimeria recorded. The limited distribution of many Epimeria species of the Southern Ocean is presumably related to the poor dispersal capacity in most species of the genus. Indeed with the exception of the pelagic and semi-pelagic species of the subgenus Epimeriella, they are heavy strictly benthic organisms without larval stages, and they have no exceptional level of eurybathy for Antarctic amphipods. Therefore, stretches deeper than 1000 m seem to be efficient geographical barriers for many Epimeria species, but other isolating factors (e.g., large stretches poor in epifauna) might also be at play. The existence of endemic shelf species with limited dispersal capacities in the Southern Ocean (like many Epimeria) suggests the existence of multiple ice-free shelf or upper slope refugia during the Pleistocene glaciations within the distributional and bathymetric range of these species. Genera with narrow range endemics like Epimeria would be excellent model taxa for locating hotspots of Antarctic endemism, and thus potentially play a role in proposing meaningful Marine Protected Areas (MPAs) in the Southern Ocean.The present monograph includes general systematic considerations on the family Epimeriidae, a revision of the genus Epimeria Costa in Hope, 1851 in the Southern Ocean, and a shorter account on putatively related eusiroid taxa occurring in Antarctic and sub-Antarctic seas. The former epimeriid genera Actinacanthus Stebbing, 1888 and Paramphithoe Bruzelius, 1859 are transferred to other families, respectively to the Acanthonotozomellidae Coleman &amp; J.L. Barnard, 1991 and the herein re-established Paramphithoidae G.O. Sars, 1883, so that only Epimeria and Uschakoviella Gurjanova, 1955 are retained within the Epimeriidae Boeck, 1871. The genera Apherusa Walker, 1891 and Halirages Boeck, 1891, which are phylogenetically close to Paramphithoe, are also transferred to the Paramphithoidae. The validity of the suborder Senticaudata Lowry &amp; Myers, 2013, which conflicts with traditional and recent concepts of Eusiroidea Stebbing, 1888, is questioned. Eight subgenera are recognized for Antarctic and sub-Antarctic species of the genus Epimeria: Drakepimeria subgen. nov., Epimeriella K.H. Barnard, 1930, Hoplepimeria subgen. nov., Laevepimeria subgen. nov., Metepimeria Schellenberg, 1931, Pseudepimeria Chevreux, 1912, Subepimeria Bellan-Santini, 1972 and Urepimeria subgen. nov. The type subgenus Epimeria, as currently defined, does not occur in the Southern Ocean. Drakepimeria species are superficially similar to the type species of the genus Epimeria: E. cornigera (Fabricius, 1779), but they are phylogenetically unrelated and substantial morphological differences are obvious at a finer level. Twenty-seven new Antarctic Epimeria species are described herein: Epimeria (Drakepimeria) acanthochelon subgen. et sp. nov., E. (D.) anguloce subgen. et sp. nov., E. (D.) colemani subgen. et sp. nov., E. (D.) corbariae subgen. et sp. nov., E. (D.) cyrano subgen. et sp. nov., E. (D.) havermansiana subgen. et sp. nov., E. (D.) leukhoplites subgen. et sp. nov., E. (D.) loerzae subgen. et sp. nov., E. (D.) pandora subgen. et sp. nov., E. (D.) pyrodrakon subgen. et sp. nov., E. (D.) robertiana subgen. et sp. nov., Epimeria (Epimeriella) atalanta sp. nov., Epimeria (Hoplepimeria) cyphorachis subgen. et sp. nov., E. (H.) gargantua subgen. et sp. nov., E. (H.) linseae subgen. et sp. nov., E. (H.) quasimodo subgen. et sp. nov., E. (H.) xesta subgen. et sp. nov., Epimeria (Laevepimeria) anodon subgen. et sp. nov., E. (L.) cinderella subgen. et sp. nov., Epimeria (Pseudepimeria) amoenitas sp. nov., E. (P.) callista sp. nov., E. (P.) debroyeri sp. nov., E. (P.) kharieis sp. nov., Epimeria (Subepimeria) adeliae sp. nov., E. (S.) iota sp. nov., E. (S.) teres sp. nov. and E. (S.) urvillei sp. nov. The type specimens of E. (D.) macrodonta Walker, 1906, E. (D.) similis Chevreux, 1912, E. (H.) georgiana Schellenberg, 1931 and E. (H.) inermis Walker, 1903 are re-described and illustrated. Besides the monographic treatment of Epimeriidae from the Southern Ocean, a brief overview and identification keys are given for their putative and potential relatives from the same ocean, i.e., the Antarctic and sub-Antarctic members of the following eusiroid families: Acanthonotozomellidae Coleman &amp; J.L. Barnard, 1991, Dikwidae Coleman &amp; J.L. Barnard, 1991, Stilipedidae Holmes, 1908 and Vicmusiidae Just, 1990. This overview revealed the existence of a new large and characteristic species of Alexandrella Chevreux, 1911, A. chione sp. nov. but also shows that the taxonomy of that genus remains poorly known and that several ‘variable widespread eurybathic species’ probably are species complexes. Furthermore, the genera Bathypanoploea Schellenberg, 1939 and Astyroides Birstein &amp; Vinogradova, 1960 are considered to be junior synonyms of Alexandrella. Alexandrella mixta Nicholls, 1938 and A. pulchra Ren in Ren &amp; Huang, 1991 are re-established herein, as valid species. It is pointed out that this insufficient taxonomic knowledge of Antarctic amphipods impedes ecological and biogeographical studies requiring precise identifications. Stacking photography was used for the first time to provide iconographic support in amphipod taxonomy, and proves to be a rapid and efficient illustration method for large tridimensionally geometric species. A combined morphological and molecular approach was used whenever possible for distinguishing Epimeria species, which were often very similar (albeit never truly cryptic) and sometimes exhibited allometric and individual variations. However in several cases, taxa were characterized by morphology only, whenever the specimens available for study were inappropriately fixed or when no sequences could be obtained. A large number of Epimeria species, formerly considered as eurybathic and widely distributed, proved to be complexes of species, with a narrower (overlapping or not) distribution. The distributional range of Antarctic Epimeria is very variable from species to species. Current knowledge indicates that some species from the Scotia Arc and the tip of the Antarctic Peninsula are narrow range endemics, sometimes confined to one island, archipelago, or ridge (South Georgia, South Orkney Islands, Elephant Island or Bruce Ridge); other species have a distribution encompassing a broader region, such as the eastern shelf of the Weddell Sea, or extending from the eastern shelf of the Weddell Sea to Adélie Coast. The most widely distributed species are E. (D.) colemani subgen. et sp. nov., E. (E.) macronyx (Walker, 1906), E. (H.) inermis Walker, 1903 and E. (L.) walkeri (K.H. Barnard, 1930), which have been recorded from the Antarctic Peninsula/South Shetland Islands area to the western Ross Sea. Since restricted distributions are common among Antarctic and sub-Antarctic Epimeria, additional new species might be expected in areas such as the Kerguelen Plateau, eastern Ross Sea, Amundsen Sea and the Bellingshausen Sea or isolated seamounts and ridges, where there are currently no Epimeria recorded. The limited distribution of many Epimeria species of the Southern Ocean is presumably related to the poor dispersal capacity in most species of the genus. Indeed with the exception of the pelagic and semi-pelagic species of the subgenus Epimeriella, they are heavy strictly benthic organisms without larval stages, and they have no exceptional level of eurybathy for Antarctic amphipods. Therefore, stretches deeper than 1000 m seem to be efficient geographical barriers for many Epimeria species, but other isolating factors (e.g., large stretches poor in epifauna) might also be at play. The existence of endemic shelf species with limited dispersal capacities in the Southern Ocean (like many Epimeria) suggests the existence of multiple ice-free shelf or upper slope refugia during the Pleistocene glaciations within the distributional and bathymetric range of these species. Genera with narrow range endemics like Epimeria would be excellent model taxa for locating hotspots of Antarctic endemism, and thus potentially play a role in proposing meaningful Marine Protected Areas (MPAs) in the Southern Ocean.</p

Epimeria (Drakepimeria) similis d'Acoz & Verheye 2017, subgen. nov.

&lt;i&gt;Epimeria&lt;/i&gt; (&lt;i&gt;Drakepimeria&lt;/i&gt;) &lt;i&gt;similis&lt;/i&gt; subgen. nov. Chevreux, 1912 &lt;p&gt;Figs 106&ndash;124&lt;/p&gt; &lt;p&gt; &lt;i&gt;Epimeria similis&lt;/i&gt; Chevreux, 1912: 215.&lt;/p&gt; &lt;p&gt; &lt;i&gt;Epimeria similis&lt;/i&gt; &ndash; Chevreux 1913: 149, fig. 41. &mdash; Andres 1985: 124&ndash;125 (in part) &mdash; De Broyer &amp; Klages 1991: 165 (key, in part). &mdash; Coleman 2007: 54, in part, fig. 30a&ndash;b, map 11 (circle, at least in part), not plate 1 fig. e (= &lt;i&gt;Epimeria acanthochelon&lt;/i&gt; sp. nov.).&lt;/p&gt; &lt;p&gt; &lt;i&gt;Epimeria macrodonta&lt;/i&gt; f. &lt;i&gt;similis&lt;/i&gt; &ndash; Gurjanova 1955: 195.&lt;/p&gt; &lt;p&gt; &lsquo; Clade A &lt;i&gt;similis / macrodonta&lt;/i&gt; complex - SI4&rsquo; &ndash; Verheye &lt;i&gt;et al.&lt;/i&gt; 2016a, supplement: 2 (online).&lt;/p&gt; Type material &lt;p&gt; &lt;b&gt;Lectotype (designated here)&lt;/b&gt;&lt;/p&gt; &lt;p&gt; RV &lt;i&gt;Pourquoi Pas?&lt;/i&gt; Cruises:&lt;/p&gt; &lt;p&gt;SOUTHERN OCEAN: undissected ovigerous &female;, second French Antarctic expedition 1908&ndash;1910, Draguage XVII, South Shetlands, King George Island, Admiralty Bay, 420 m (n&deg; 713) (MNHN Am. 5984 and MNHN-IU-2013-17865).&lt;/p&gt; &lt;p&gt; &lt;b&gt;Paralectotype (designated here)&lt;/b&gt;&lt;/p&gt; &lt;p&gt; RV &lt;i&gt;Pourquoi Pas?&lt;/i&gt; Cruises:&lt;/p&gt; &lt;p&gt;SOUTHERN OCEAN: 1 &female; dissected by E. Chevreux, second French Antarctic expedition 1908&ndash;1910, Draguage XVII, South Shetlands King George Island, Admiralty Bay, 420 m (MNHN Am. 3095 and MNHN-IU-2013-17864).&lt;/p&gt; Other material examined &lt;p&gt; RV &lt;i&gt;Polarstern&lt;/i&gt; cruises:&lt;/p&gt; &lt;p&gt;SOUTHERN OCEAN: 3 specs, cruise PS69, ANT-XXIII/8, stn 604-1, Elephant Island, 61&deg;20.52ʹ S, 55&deg;09.72ʹ W to 61&deg;20.11ʹ S, 55&deg;07.26ʹ W, 286&ndash;407 m, bottom trawl, 19 Dec. 2006, coll. C. d&rsquo;Udekem d&rsquo;Acoz and H. Robert (RBINS, INV. 132980); 1 spec. with a true posterodorsal bump on second body segment, cruise PS69, ANT-XXIII/8, stn 604-1, Elephant Island, 61&deg;20.52ʹ S, 55&deg;09.72ʹ W to 61&deg;20.11ʹ S, 55&deg;07.26ʹ W, 286&ndash;407 m, bottom trawl, 19 Dec. 2006, coll. C. d&rsquo;Udekem d&rsquo;Acoz and H. Robert (RBINS, INV. 122555); 2 specs, cruise PS69, ANT-XXIII/8, stn 608-1, Elephant Island, 61&deg;11.34ʹ S, 54&deg;43.17ʹ W to 61&deg;11.80ʹ S, 54&deg;40.05ʹ W, 284&ndash;293 m, bottom trawl, 20 Dec. 2006, coll. C. d&rsquo;Udekem d&rsquo;Acoz and H. Robert (RBINS, INV. 132982); 1 spec., cruise PS69, ANT-XXIII/8, stn 610-1, Elephant Island, 60&deg;58.59ʹ S, 55&deg;08.39ʹ W to 60&deg;58.05ʹ S, 55&deg;05.00ʹ W, 287&ndash;311 m, bottom trawl, 21 Dec. 2006, coll. C. d&rsquo;Udekem d&rsquo;Acoz and H. Robert (RBINS, INV. 122550); 2 specs, cruise PS69, ANT-XXIII/8, stn 614-3/4/5, Elephant Island, 60&deg;52.37ʹ S, 55&deg;29.80ʹ W to 60&deg;52.71ʹ S, 55&deg;27.83ʹ W, 248&ndash;265 m, a lot of epifauna, Rauschert dredge and Agassiz trawl, 22 Dec. 2006, coll. C. d&rsquo;Udekem d&rsquo;Acoz and H. Robert (RBINS, INV. 132984); 2 juvs, cruise PS69, ANT-XXIII/8, stn 614-3/4/5, Elephant Island, 60&deg;52.37ʹ S, 55&deg;29.80ʹ W to 60&deg;52.71ʹ S, 55&deg;27.83ʹ W, 248&ndash;265 m, a lot of epifauna, Rauschert dredge and Agassiz trawl, 22 Dec. 2006, coll. C. d&rsquo;Udekem d&rsquo;Acoz and H. Robert (RBINS, INV. 122554); 1 spec., alcohol-fixed, cruise PS69, ANT-XXIII/8, stn 624-3, Elephant Island, Agassiz trawl, 61&deg;00.23ʹ S, 55&deg;58.53ʹ W to 61&deg;00.76ʹ S, 55&deg;59.20ʹ W, 287&ndash;319 m, 23 Dec. 2006, coll. C. d&rsquo;Udekem d&rsquo;Acoz and H. Robert (RBINS, INV. 122479); 4 specs, cruise PS69, ANT-XXIII/8, stn 627-1, Elephant Island, 60&deg;59.00ʹ S, 55&deg;42.36ʹ W to 60&deg;57.62ʹ S, 55&deg;40.19ʹ W, 90&ndash;102 m, bottom trawl, 24 Dec. 2006, coll. C. d&rsquo;Udekem d&rsquo;Acoz and H. Robert (RBINS, INV. 132979); 5 specs, cruise PS69, ANT-XXIII/8, stn 642-1, Elephant Island, 61&deg;04.38ʹ S, 55&deg;59.81ʹ W to 61&deg;04.27ʹ S, 55&deg;58.88ʹ W, 254 m, Agassiz trawl, 27 Dec. 2006, coll. C. d&rsquo;Udekem d&rsquo;Acoz and H. Robert (RBINS, INV. 132981); 1 small spec., cruise PS69, ANT-XXIII/8, stn 642-2, Elephant Island, 61&deg;04.28ʹ S, 55&deg;58.93ʹ W to 61&deg;04.24ʹ S, 55&deg;59.27ʹ W, 255&ndash;277 m, Rauschert dredge, 27 Dec. 2006, coll. C. d&rsquo;Udekem d&rsquo;Acoz and H. Robert (RBINS, INV. 122557); 2 specs, alcohol-fixed, cruise PS69, ANT-XXIII/8, stn 654-6, Elephant Island, 61&deg;22.80ʹ S, 56&deg;03.84ʹ W to 61&deg;23.35ʹ S, 56&deg;04.89ʹ W, 341&ndash;342 m, Agassiz trawl, 29 Dec. 2006, coll. C. d&rsquo;Udekem d&rsquo;Acoz and H. Robert (RBINS, INV. 122480); 1 small spec., cruise PS69, ANT-XXIII/8, stn 654-6, Elephant Island, 61&deg;22.80ʹ S, 56&deg;03.84ʹ W to 61&deg;23.35ʹ S, 56&deg;04.89ʹ W, 341&ndash;342 m, Agassiz trawl, 29 Dec. 2006, coll. C. d&rsquo;Udekem d&rsquo;Acoz and H. Robert (RBINS, INV. 122556); 2 &female;&female;, cruise PS69, ANT-XXIII/8, stn 654-6, Elephant Island, 61&deg;22.80ʹ S, 56&deg;03.84ʹ W to 61&deg;23.35ʹ S, 56&deg;04.89ʹ W, 341&ndash;342 m, Agassiz trawl, 29 Dec. 2006, coll. C. d&rsquo;Udekem d&rsquo;Acoz and H. Robert (RBINS, INV. 132983); 5 specs, cruise PS69, ANT-XXIII/8, stn 676-1, north of Livingstone Island, 62&deg;11.06ʹ S, 60&deg;47.49ʹ W to 62&deg;09.65ʹ S, 60&deg;49.56ʹ W, 418&ndash;472 m, bottom trawl, 2 Dec. 2007, coll. C. d&rsquo;Udekem d&rsquo;Acoz and H. Robert (RBINS, INV. 122544); 2 specs, cruise PS69, ANT-XXIII/8, stn 680-5, northeast of Livingstone Island, 62&deg;23.37ʹ S, 61&deg;25.58ʹ W 62&deg;22.75ʹ S, 61&deg;25.97ʹ W, 324&ndash;349 m, Agassiz trawl, 3 Jan. 2007, coll. C. d&rsquo;Udekem d&rsquo;Acoz and H. Robert (RBINS, INV. 122553); 1 &female;, specimen used for detailed illustrations, cruise PS81, ANT-XXIX/3, stn 193-8, Bransfield Strait, 62&deg;43.73ʹ S, 57&deg;29.04ʹ W to 62&deg;43.80ʹ S, 57&deg;29.40ʹ W, 426-431 m, 23 Feb. 2013, coll. C. d&rsquo;Udekem d&rsquo;Acoz and M. Verheye (RBINS, INV. 122956A) [extraction P36; Genbank nr, 28S: KU759680]; 3 &female;&female;, cruise PS81, ANT- XXIX/3, stn 193-8, Bransfield Strait, 62&deg;43.73ʹ S, 57&deg;29.04ʹ W to 62&deg;43.80ʹ S, 57&deg;29.40ʹ W, 426-431 m, 23 Feb. 2013, coll. C. d&rsquo;Udekem d&rsquo;Acoz and M. Verheye (RBINS, INV. 122956B); 6 specs, cruise PS81, ANT-XXIX/3, stn 193-9, Bransfield Strait, 62&deg;43.50ʹ S, 57&deg;27.92ʹ W to 62&deg;43.53ʹ S, 57&deg;28.28ʹ W, 420&ndash;431 m, sponge bottom, 23 Feb. 2013, coll. C. d&rsquo;Udekem d&rsquo;Acoz and M. Verheye (RBINS, INV. 122961); 1 spec., cruise PS81, ANT-XXIX/3, stn 217-6, Bransfield Strait, 62&deg;53.45ʹ S, 58&deg;13.06ʹ W to 62&deg;53.42ʹ S, 58&deg;13.41ʹ W, 461&ndash;483 m, rich sponge bottom,Agassiz trawl, 2 Mar. 2013, coll. C. d&rsquo;Udekem d&rsquo;Acoz and M. Verheye (RBINS, INV. 122922B) [extraction P38; Genbank nr, 28S: KU759682].&lt;/p&gt; Description &lt;p&gt;ROSTRUM. Long, reaching about tip of article 1 of peduncle of antenna 1 (teeth excluded), weakly curved, sharp-tipped in lateral view.&lt;/p&gt; &lt;p&gt;EYE. Very large, elliptic.&lt;/p&gt; &lt;p&gt;PEREION&ndash;PLEOSOME TOOTH PATTERN. Pereionite 1 without any trace of mid-dorsal tooth, with pair of very low non-carinate dorsolateral swellings; pereionite 2 nearly as broad as pereionite 1, with or without very small blunt-tipped mid-dorsal tooth or bump, and with pair of dorsolateral non-carinate swellings or very blunt teeth; pereionite 3 with medium-sized blunt-tipped mid-dorsal tooth and pair of small dorsolateral non-carinate blunt teeth; pereionite 3 to pleonite 2 with acute-tipped broad regularly curved mid-dorsal tooth (nearly same shape and size on all these segments) and pair of dorsolateral non-carinate acute-tipped teeth (pleonites 1&ndash;2 without second pair of dorsolateral teeth); pleonite 3 with dorsal sharp carina with very weak median notch (lobe anterior to notch very low) and obliquely produced posteriorly into an a broad acute and sharp triangular tooth, and pair of dorsolateral non-carinate acute-tipped teeth.&lt;/p&gt; &lt;p&gt;COXAE 1&ndash;3. Strongly carinate and distally sharp.&lt;/p&gt; &lt;p&gt;COXA 4. Anterodorsal and anteroventral border nearly straight, joined by low and blunt angular discontinuity, anterior angle not strongly projecting forward; ventral tooth very long and styliform; lateral carina with lateral well-developed and sharp triangular tooth pointing obliquely backwards.&lt;/p&gt; &lt;p&gt;COXA 5. With sharp and broadly triangular, carinate, lateral tooth pointing obliquely backwards.&lt;/p&gt; &lt;p&gt;COXA 6. With mid-sized, sharp and narrowly triangular, carinate, lateral tooth pointing obliquely backwards; posteroventral corner produced into a triangular tooth.&lt;/p&gt; &lt;p&gt;COXA 7. With ventral and posterior border straight, with posteroventral angle produced into a strong tooth.&lt;/p&gt; &lt;p&gt;EPIMERAL PLATES 1&ndash;3. Posteroventral angle produced into a very long styliform tooth.&lt;/p&gt; &lt;p&gt;UROSOME TOOTH PATTERN. Urosomite 1 with sharp triangular process pointing upwards; urosomite 2 without pair of small posterior dorsolateral teeth pointing upwards.&lt;/p&gt; &lt;p&gt;TELSON. Cleft on 0.25; tips of lobes rounded, slit fairly narrow.&lt;/p&gt; &lt;p&gt;PEDUNCLE OF ANTENNA 1. Article 1 with long lateral and medial teeth nearly reaching mid of article 2 (teeth excluded) and long ventral tooth reaching tip of article 2 (teeth excluded); article 2 with long lateral tooth nearly reaching tip of article 3 (tooth excluded), with medial tooth slightly overreaching article 3 (tooth excluded), with ventral tooth slightly overreaching tip of article 3 (tooth excluded); article 3 with very long ventral tooth, longer than article itself.&lt;/p&gt; &lt;p&gt;GNATHOPODS 1&ndash;2. Carpus and propodus of normal slenderness; propodus not narrowing distally, palm distinct.&lt;/p&gt; &lt;p&gt;PEREIOPODS 5&ndash;7. Merus, carpus and propodus slender; basis of pereiopods 5&ndash;6 of normal width, with posteroproximal process rounded and strongly protruding, with posterodistal tooth strong; basis of pereiopod 7 very broad with posterodistal tooth sharp, followed more proximally by small concavity, directed posteriorly.&lt;/p&gt; Colour pattern &lt;p&gt;Whitish with faint orange marks on body; peduncle of antenna 1 carpus and propodus of pereiopods and uropods also tinged with orange. Eyes reddish.&lt;/p&gt; Body length &lt;p&gt;Up to 40 mm.&lt;/p&gt; Distribution &lt;p&gt;Elephant Island to Bransfield Strait, 90&ndash;483 m (present data).&lt;/p&gt; Remarks &lt;p&gt; The tip of the lateral tooth of coxa 4 is slightly damaged in the syntype of &lt;i&gt;Epimeria similis&lt;/i&gt; illustrated by Chevreux (1913). This explains why the orientation of that tooth does not seem accurate on the drawings made by that author. Specimens of &lt;i&gt;E. similis&lt;/i&gt; from Elephant Island look identical to specimens recorded further south, except for the absence of a mid-dorsal tooth on pereionite 2, which is either smooth or with a trace of bump. The difference is presumably size-related. &lt;i&gt;Epimeria similis&lt;/i&gt; from Bransfield Strait and King George Island often reach a larger size than those of Elephant Island, and only the large ones have the extra tooth. So the specimens from Elephant Island are considered herein as small &lt;i&gt;E. similis&lt;/i&gt; s. str.&lt;/p&gt; &lt;p&gt; The collecting station of the &lt;i&gt;E. similis&lt;/i&gt; illustrated by Coleman (2007) on his figure 30 are 61&deg;03.6ʹ S, 54&deg;41.6ʹ W [Elephant Island]; 15 Dec. 1987, leg. Coleman, 358&ndash; 332 m, bottom trawl (Coleman pers. com.). This specimen appears to be a true &lt;i&gt;E. similis&lt;/i&gt;. On the other hand, the specimen illustrated by a colour photograph on his plate 1, fig. e is presumably &lt;i&gt;Epimeria acanthochelon&lt;/i&gt; sp. nov. (see discussion on that species).&lt;/p&gt; &lt;p&gt; It seems that &lt;i&gt;E. similis&lt;/i&gt; and the similar and closely related &lt;i&gt;E. acanthochelon&lt;/i&gt; sp. nov. have non-overlapping distributions. &lt;i&gt;Epimeria similis&lt;/i&gt; was recorded from the South Shetland Islands and the tip of the Antarctic Peninsula. &lt;i&gt;Epimeria acanthochelon&lt;/i&gt; sp. nov. was recorded on the Ad&eacute;lie Coast (supported by 28S rDNA) and on the eastern shelf of the Weddell Sea (identification based on morphology only). See key of &lt;i&gt;Drakepimeria&lt;/i&gt; and account on &lt;i&gt;E. acanthochelon&lt;/i&gt; sp. nov. for differences with &lt;i&gt;E. similis&lt;/i&gt;.&lt;/p&gt;Published as part of &lt;i&gt;d'Acoz, Cédric d'Udekem &amp; Verheye, Marie L., 2017, Epimeria of the Southern Ocean with notes on their relatives (Crustacea, Amphipoda, Eusiroidea), pp. 1-553 in European Journal of Taxonomy 359&lt;/i&gt; on pages 60-63, DOI: 10.5852/ejt.2017.359, &lt;a href="http://zenodo.org/record/3855694"&gt;http://zenodo.org/record/3855694&lt;/a&gt

Epimeria (Drakepimeria) d'Acoz & Verheye 2017, subgen. nov.

Incertae sedis: &lt;i&gt;Epimeria&lt;/i&gt; (&lt;i&gt;Drakepimeria&lt;/i&gt;) subgen. nov. sp. 2 &lt;p&gt; &lt;i&gt;Epimeria&lt;/i&gt; sp. &ndash; Andres 1985: 127, fig. 10, 11A.&lt;/p&gt; Distribution &lt;p&gt;South Shetland Islands: Clarence Island, 0&ndash; 145 m.&lt;/p&gt; Remark &lt;p&gt; The description of &lt;i&gt;Epimeria&lt;/i&gt; sp. by Andres (1985) is based on two tiny (7 mm) male specimens. It exhibits similarities with &lt;i&gt;E. leukhoplites&lt;/i&gt; sp. nov., &lt;i&gt;E. reoproi&lt;/i&gt; and &lt;i&gt;E. vaderi&lt;/i&gt;, of which the description is based on much larger specimens. It is likely that Andres&rsquo; (1985) specimens are juveniles of one of these species.&lt;/p&gt;Published as part of &lt;i&gt;d'Acoz, Cédric d'Udekem &amp; Verheye, Marie L., 2017, Epimeria of the Southern Ocean with notes on their relatives (Crustacea, Amphipoda, Eusiroidea), pp. 1-553 in European Journal of Taxonomy 359&lt;/i&gt; on page 65, DOI: 10.5852/ejt.2017.359, &lt;a href="http://zenodo.org/record/3855694"&gt;http://zenodo.org/record/3855694&lt;/a&gt

Epimeria (Metepimeria) intermedia Schellenberg 1931

&lt;i&gt;Epimeria&lt;/i&gt; (&lt;i&gt;Metepimeria&lt;/i&gt;) &lt;i&gt;intermedia&lt;/i&gt; Schellenberg, 1931 forma B &lt;p&gt; &lt;i&gt;Epimeria intermedia&lt;/i&gt; &ndash; K.H. Barnard, 1932: 177, figs 104c, 109. &mdash; Wakabara &amp; Serejo, 1999: 642 (key, in part). &mdash; Coleman, 2007: 42 (in part), not fig. 20a&ndash;b (= &lt;i&gt;Epimeria&lt;/i&gt; (&lt;i&gt;Metepimeria&lt;/i&gt;) &lt;i&gt;intermedia&lt;/i&gt; forma A), map 10 (circle, in part).&lt;/p&gt; &lt;p&gt; &lt;i&gt;Epimeria&lt;/i&gt; sp. n. 2 &ndash; Rauschert &amp; Arntz, 2015: 60, plate 53, unnumbered photograph.&lt;/p&gt; &lt;p&gt; &lt;i&gt;Epimeria&lt;/i&gt; sp. n. 3 &ndash; Rauschert &amp; Arntz, 2015: 125 (&lt;i&gt;non Epimeria&lt;/i&gt; sp. n. 3 p. 54 pl. 61).&lt;/p&gt; &lt;p&gt; &lt;i&gt;non&lt;/i&gt; &lt;i&gt;Epimeria intermedia&lt;/i&gt; Schellenberg, 1931: 161, fig. 84, pl. 1 fig. F. (= &lt;i&gt;Epimeria&lt;/i&gt; (&lt;i&gt;Metepimeria&lt;/i&gt;)&lt;/p&gt; &lt;p&gt; &lt;i&gt;intermedia&lt;/i&gt; Schellenberg, 1931 forma A).&lt;/p&gt; Body length &lt;p&gt;15 mm (K.H. Barnard 1932).&lt;/p&gt; Colour pattern &lt;p&gt; Pure white (Rauschert &amp; Arntz 2015: 60, as &lt;i&gt;Epimeria&lt;/i&gt; sp. n. 2).&lt;/p&gt; Distribution &lt;p&gt;South Georgia, 88&ndash;273 m (K.H. Barnard 1932); Shag Rocks, 284 m (see remarks).&lt;/p&gt; Remarks &lt;p&gt; There are substantial differences between the illustrations of &lt;i&gt;E. intermedia&lt;/i&gt; given by Schellenberg (1931) and Coleman (2007) on one hand, and those of K.H. Barnard (1932). Coleman (2007) questions the conspecificity of these specimens. We agree and treat them as separate forma A and B. However we refrain to attribute them a formal taxonomic status, as no direct examination of these specimens was possible.&lt;/p&gt; &lt;p&gt; Rauschert &amp; Arntz (2015) gave a colour photograph of a juvenile (6 mm) named &ldquo; &lt;i&gt;Epimeria&lt;/i&gt; sp. n. 2&rdquo;, which corresponds to the drawings of &lt;i&gt;Epimeria intermedia&lt;/i&gt; forma B given by K.H. Barnard (1932). The collection details of the specimen were given in an early draft of the book: ANT-XIX/ 5 in stn 169-1, 53&deg;22.94ʹ S, 42&deg;41.37ʹ W to 53&deg;22.89ʹ S, 42&deg;41.50ʹ W (Shag Rocks), at 284 m.&lt;/p&gt;Published as part of &lt;i&gt;d'Acoz, Cédric d'Udekem &amp; Verheye, Marie L., 2017, Epimeria of the Southern Ocean with notes on their relatives (Crustacea, Amphipoda, Eusiroidea), pp. 1-553 in European Journal of Taxonomy 359&lt;/i&gt; on pages 118-119, DOI: 10.5852/ejt.2017.359, &lt;a href="http://zenodo.org/record/3855694"&gt;http://zenodo.org/record/3855694&lt;/a&gt

Alexandrella mandibulata Berge & Vader 2005

&lt;i&gt;Alexandrella mandibulata&lt;/i&gt; Berge &amp; Vader, 2005 &lt;p&gt; &lt;i&gt;Alexandrella mandibulata&lt;/i&gt; Berge &amp; Vader, 2005a: 1335&ndash;1339, figs 4&ndash;6.&lt;/p&gt; &lt;p&gt; &lt;i&gt;Alexandrella mandibulata&lt;/i&gt; &ndash; Serejo 2014: 139 (key).&lt;/p&gt; Distribution &lt;p&gt;East of South Georgia, 55&deg;04ʹ S, 33&deg;57ʹ W to 55&deg;00ʹ S, 33&deg;59ʹ W, 3138&ndash;3239 m (Berge &amp; Vader 2005a).&lt;/p&gt;Published as part of &lt;i&gt;d'Acoz, Cédric d'Udekem &amp; Verheye, Marie L., 2017, Epimeria of the Southern Ocean with notes on their relatives (Crustacea, Amphipoda, Eusiroidea), pp. 1-553 in European Journal of Taxonomy 359&lt;/i&gt; on pages 172-173, DOI: 10.5852/ejt.2017.359, &lt;a href="http://zenodo.org/record/3855694"&gt;http://zenodo.org/record/3855694&lt;/a&gt

Epimeria (Hoplepimeria) gargantua d'Acoz & Verheye 2017, subgen. et sp. nov.

&lt;i&gt;Epimeria&lt;/i&gt; (&lt;i&gt;Hoplepimeria&lt;/i&gt;) &lt;i&gt;gargantua&lt;/i&gt; subgen. et sp. nov. &lt;p&gt;urn:lsid:zoobank.org:act: E5FDFA56-F77B-46D9-9665-644728A7970C&lt;/p&gt; &lt;p&gt;Figs 145&ndash;151&lt;/p&gt; &lt;p&gt; &lt;i&gt;Epimeria robusta&lt;/i&gt; Klages, 1988: 73, unnumbered fig., 76, 82, figs 20a&ndash;b.&lt;/p&gt; &lt;p&gt; &lt;i&gt;Epimeria robustoides&lt;/i&gt; ? L&ouml;rz &amp; Coleman &lt;i&gt;in&lt;/i&gt; L&ouml;rz &lt;i&gt;et al.,&lt;/i&gt; 2009: 10, possibly in part, possibly fig. 10A, not figs 2&ndash;5 (= &lt;i&gt;E. robustoides&lt;/i&gt;).&lt;/p&gt; &lt;p&gt; &lt;i&gt;Epimeria robusta&lt;/i&gt; &ndash; Coleman 1994: 560, in part, fig. 5D only.&lt;/p&gt; &lt;p&gt; &lsquo; Clade G &lt;i&gt;robustoides / robusta&lt;/i&gt; complex - RO1&rsquo; &ndash; Verheye &lt;i&gt;et al.&lt;/i&gt; 2016a, supplement: 4 (online). &lt;i&gt;non&lt;/i&gt; &lt;i&gt;Epimeria robusta&lt;/i&gt; K.H. Barnard, 1930: 375, figs 40a, 41.&lt;/p&gt; &lt;p&gt; &lt;i&gt;non&lt;/i&gt; &lt;i&gt;Epimeria robustoides&lt;/i&gt; L&ouml;rz &amp; Coleman &lt;i&gt;in&lt;/i&gt; L&ouml;rz &lt;i&gt;et al.&lt;/i&gt;, 2009: 10, figs 2&ndash;5.&lt;/p&gt; Etymology &lt;p&gt; Gargantua is a giant and one of the main characters in the tales of Fran&ccedil;ois Rabelais, such as &lsquo;La vie tr&egrave;s horrifique du grand Gargantua, p&egrave;re de Pantagruel&rsquo;. The name, which is a noun in apposition, alludes to the huge size of the species, which is the largest known &lt;i&gt;Epimeria&lt;/i&gt; species.&lt;/p&gt; Type material &lt;p&gt; &lt;b&gt;Holotype&lt;/b&gt;&lt;/p&gt; &lt;p&gt; RV &lt;i&gt;Polarstern&lt;/i&gt; cruises:&lt;/p&gt; &lt;p&gt;SOUTHERN OCEAN: &female;, cruise PS81, ANT-XXIX/3, Bransfield Strait, stn 196-8, 62&deg;47.80ʹ S, 57&deg;5.35ʹ W to 62&deg;47.63ʹ S, 57&deg;5.63ʹ W, 542&ndash;580 m, trawl haul with huge stones and a lot of life, Agassiz trawl, 24 Feb. 2013, coll. C. d&rsquo;Udekem d&rsquo;Acoz and M. Verheye (RBINS, INV. 122937A) [extraction ANT 33; Genbank nr, COI: KU870820, 28S: KU759592].&lt;/p&gt; &lt;p&gt; &lt;b&gt;Paratypes&lt;/b&gt;&lt;/p&gt; &lt;p&gt; RV &lt;i&gt;Polarstern&lt;/i&gt; cruises:&lt;/p&gt; &lt;p&gt;SOUTHERN OCEAN: 1 medium-sized spec., cruise PS69, ANT-XXIII/8, stn 662-1, between Elephant Island and King George Island, 61&deg;35.91ʹ S, 57&deg;17.04ʹ W to 61&deg;35.41ʹ S, 57&deg;20.60ʹ W, 425&ndash;432 m, bottom trawl, 30 Dec. 2006, coll. C. d&rsquo;Udekem d&rsquo;Acoz and H. Robert (RBINS, INV. 122491); 2 large specs, cruise PS69, ANT-XXIII/8, stn 663-1, northeast of King George Island, 61&deg;38.18ʹ S, 57&deg;33.17ʹ W to 61&deg;38.02ʹ S, 57&deg;37.16ʹ W, bottom trawl, 432&ndash;434 m, 30 Dec. 2006, coll. C. d&rsquo;Udekem d&rsquo;Acoz and H. Robert (RBINS, INV. 122494); 5 specs, cruise PS81, ANT-XXIX/3, Bransfield Strait, stn 196-8, 62&deg;47.80ʹ S, 57&deg;5.35ʹ W to 62&deg;47.63ʹ S, 57&deg;5.63ʹ W, 542&ndash;580 m, trawl haul with huge stones and a lot of life, Agassiz trawl, 24 Feb. 2013, coll. C. d&rsquo;Udekem d&rsquo;Acoz and M. Verheye (RBINS, INV. 122937B); 1 spec., cruise PS81, ANT-XXIX/3, Bransfield Strait, stn 217-6, 62&deg;53.45ʹ S, 58&deg;13.06ʹ W to 62&deg;53.42ʹ S, 58&deg;13.41ʹ W, 461&ndash;483 m, rich sponge bottom, Agassiz trawl, 2 Mar. 2013, coll. C. d&rsquo;Udekem d&rsquo;Acoz and M. Verheye (RBINS, INV. 122927) [extraction K37; Genbank nr, COI: KU870869, 28S: KU759649]; 1 spec., cruise PS81, ANT-XXIX/3, Bransfield Strait, stn 217-6, 62&deg;53.45ʹ S, 58&deg;13.06ʹ W to 62&deg;53.42ʹ S, 58&deg;13.41ʹ W, 461&ndash;483 m, rich sponge bottom, Agassiz trawl, 2 Mar. 2013, coll. C. d&rsquo;Udekem d&rsquo;Acoz and M. Verheye (RBINS, INV. 122928) [extraction K38; Genbank nr, COI: KU870870, 28S: KU759650]; 7 specs, cruise PS81, ANT-XXIX/3, Bransfield Strait, stn 217-6, 62&deg;53.45ʹ S, 58&deg;13.06ʹ W to 62&deg;53.42ʹ S, 58&deg;13.41ʹ W, 461&ndash;483 m, rich sponge bottom, Agassiz trawl, 2 Mar. 2013, coll. C. d&rsquo;Udekem d&rsquo;Acoz and M. Verheye (RBINS, INV. 132957); 1 spec., cruise PS81, ANT-XXIX/3, Bransfield Strait, stn 217- 6, 62&deg;53.45ʹ S, 58&deg;13.06ʹ W to 62&deg;53.42ʹ S, 58&deg;13.41ʹ W, 461&ndash;483 m, rich sponge bottom, Agassiz trawl, 2 Mar. 2013, coll. C. d&rsquo;Udekem d&rsquo;Acoz and M. Verheye (MNHN-IU-2014-7333, removed from RBINS, INV. 132957); 1 spec., cruise PS81, ANT-XXIX/3, Bransfield Strait, stn 227-2, 62&deg;55.83ʹ S, 58&deg;41.09ʹ W to 62&deg;55.76ʹ S, 58&deg;41.46ʹ W, 562&ndash;564 m, mud, Agassiz trawl, 5 Mar. 2013, RBINS, coll. C. d&rsquo;Udekem d&rsquo;Acoz and M. Verheye (RBINS, INV. 122939) [extraction ANT 40; Genbank nr, COI: KU870826, 28S: KU759599].&lt;/p&gt; Description &lt;p&gt;ROSTRUM. Medium-sized, not reaching tip of article 1 of peduncle of antenna 1, anteriorly distinctly and regularly curved, ventrally straight, fairly narrow and subacute in lateral view; fairly narrow and with very weakly convex converging borders in frontal view.&lt;/p&gt; &lt;p&gt;EYE. Very large, broadly elliptic to more or less reniform. PEREION&ndash;PLEOSOME TOOTH PATTERN. Pereionites 1&ndash;7 smooth; pleonite 1 dorsally weakly carinate, very weakly convex, with distinct posterior bump; pleonite 2 dorsally distinctly carinate, with extremely low (nearly inconspicuous) proximal rounded lobe followed by extremely weak (nearly inconspicuous) concavity, posteriorly produced into a bluntly triangular tooth projecting backwards; pleonite 3 dorsally distinctly carinate with median very low rounded lobe, followed by distinct concavity, terminated by a blunt tooth directed upwards.&lt;/p&gt; &lt;p&gt;COXAE 1&ndash;3. Not carinate, apically subacute.&lt;/p&gt; &lt;p&gt;COXA 4. Anterodorsal border nearly straight (inconspicuously concave), anteroventral border straight, these two borders being joined by blunt but broad, very distinct squared angle (anterior corner), which is slightly projecting forward; ventral corner forming a very obtuse angle (ventral projection very short and very broad); lateral carina absent; posteroventral border nearly straight (inconspicuously convex).&lt;/p&gt; &lt;p&gt;COXA 5. Broad, with surface smooth, with posterior border inconspicuously concave (nearly straight), with posteroventral corner forming a blunt tooth (shape: acute triangle) projecting backwards and not laterally (no tooth or corner visible in dorsal view).&lt;/p&gt; &lt;p&gt;COXA 6. With posterior border very weakly concave, with posteroventral corner forming a blunt tooth (shape: narrow acute triangle) projecting backwards and not laterally (no tooth or corner visible in dorsal view).&lt;/p&gt; &lt;p&gt;COXA 7. Posteriorly weakly rounded.&lt;/p&gt; &lt;p&gt;EPIMERAL PLATES 1&ndash;3. Posteroventral angle: angulate in plate 1, produced into a medium-sized tooth in plates 2&ndash;3.&lt;/p&gt; &lt;p&gt;UROSOME TOOTH PATTERN. Urosomite 1 with well developed blunt-tipped process of which both the anterior and the posterior borders have an angulate concavity (the anterior deeper); urosomite 3 with dorsolateral borders weakly concave and posteriorly produced into a sharp triangular tooth.&lt;/p&gt; &lt;p&gt;TELSON. Cleft nearly on 0.2; tips of lobes triangular and subacute, notch very broadly V-shaped and subacute at its deepest point.&lt;/p&gt; &lt;p&gt;GNATHOPODS 1&ndash;2. Carpus and propodus very broad; propodus expanding distally, palm distinct.&lt;/p&gt; &lt;p&gt;PEREIOPODS 5&ndash;7. Merus, carpus and propodus fairly broad; dactylus small, very curved, with long unguis; basis of pereiopods 5&ndash;6 broad, with posteroproximal process present, sword-like, projecting obliquely, with posterodistal corner produced into a triangular tooth (with tip subacute), projecting backwards; basis of pereiopod 7 broad; posterior border with proximal 0.4 with weak concavity, with distal 0.6 deeply concave, with posterodistal corner forming a narrowly triangular tooth projecting backwards.&lt;/p&gt; Colour pattern &lt;p&gt;Body and coxae pure white, gnathopods and oral field purplish; antennae and pereiopods 3&ndash;4 pale pink; pereiopods 5&ndash;7 and tailfan pure white; eyes red. This colour pattern was very consistent in all specimens examined during ANT-XXIX/3; none had spots or marks on their immaculate body.&lt;/p&gt; Body length &lt;p&gt;Up to 80 mm.&lt;/p&gt; Distribution &lt;p&gt; Between Elephant Island and King George Island; northeast of King George Island, Bransfield Strait; 404&ndash;580 m (present material; Coleman 1994: &ldquo; &lt;i&gt;Epimeria robusta&lt;/i&gt; from Elephant Island&rdquo; (specimen actually collected between Elephant and King George Islands)).&lt;/p&gt; Remarks &lt;p&gt; &lt;i&gt;Epimeria gargantua&lt;/i&gt; sp. nov. is the largest known &lt;i&gt;Epimeria&lt;/i&gt; species, both in length and body volume. &lt;i&gt;Epimeria gargantua&lt;/i&gt; sp. nov. (tip of Antarctic Peninsula) is morphologically similar to &lt;i&gt;E. robustoides&lt;/i&gt; (eastern shelf of the Weddell Sea), but these two species were identified as separate species by methods based on COI and 28S genes (Fig. 342). In &lt;i&gt;E. gargantua&lt;/i&gt; sp. nov., the dorsolateral margins of urosomite 3 are less concave and the posterodistal corner of the basis of pereiopods 5&ndash;7 sharper than in &lt;i&gt;E. robustoides&lt;/i&gt;. The colour pattern of &lt;i&gt;E. gargantua&lt;/i&gt; sp. nov. is very constant (body white, without coloured marks), whilst it is more variable in &lt;i&gt;E. robustoides&lt;/i&gt;.&lt;/p&gt;Published as part of &lt;i&gt;d'Acoz, Cédric d'Udekem &amp; Verheye, Marie L., 2017, Epimeria of the Southern Ocean with notes on their relatives (Crustacea, Amphipoda, Eusiroidea), pp. 1-553 in European Journal of Taxonomy 359&lt;/i&gt; on pages 78-81, DOI: 10.5852/ejt.2017.359, &lt;a href="http://zenodo.org/record/3855694"&gt;http://zenodo.org/record/3855694&lt;/a&gt

Epimeria (Subepimeria) teres d'Acoz & Verheye 2017, sp. nov.

&lt;i&gt;Epimeria&lt;/i&gt; (&lt;i&gt;Subepimeria&lt;/i&gt;) &lt;i&gt;teres&lt;/i&gt; sp. nov. &lt;p&gt;urn:lsid:zoobank.org:act: 87DB1EDA-29A4-493E-84BF-9A68EFF422ED&lt;/p&gt; &lt;p&gt;Figs 307&ndash;313&lt;/p&gt; &lt;p&gt; &lt;i&gt;Epimeria&lt;/i&gt; aff. &lt;i&gt;puncticulata&lt;/i&gt; &ndash;? Rauschert &amp; Arntz 2015: 61, pl. 54.&lt;/p&gt; &lt;p&gt; &lsquo;Clade B &lt;i&gt;puncticulata&lt;/i&gt; complex - PUN2ʹ &ndash; Verheye &lt;i&gt;et al.&lt;/i&gt; 2016a, supplement: 3 (online).&lt;/p&gt; &lt;p&gt; &lt;i&gt;Epimeria puncticulata&lt;/i&gt; K.H. Barnard, 1930: 377, fig. 42.&lt;/p&gt; Etymology &lt;p&gt; &lt;i&gt;Teres&lt;/i&gt;, &lt;i&gt;teres&lt;/i&gt;, &lt;i&gt;terete&lt;/i&gt;, Latin adjective meaning round and smooth, which seems appropriate for a very smooth &lt;i&gt;Epimeria&lt;/i&gt; species.&lt;/p&gt; Type material &lt;p&gt; &lt;b&gt;Holotype&lt;/b&gt;&lt;/p&gt; &lt;p&gt; RV &lt;i&gt;Polarstern&lt;/i&gt; cruises:&lt;/p&gt; &lt;p&gt;SOUTHERN OCEAN: adult, sex undetermined, cruise PS77, ANT-XXVII/3, CAMBIO, stn 248- 2, Larsen B, 65&deg;57.51ʹ S, 60&deg;28.15ʹ W to 65&deg;57.69ʹ S, 60&deg;28.30ʹ W, 196&ndash;202 m, Agassiz trawl and Rauschert dredge, 7 Mar. 2011, coll. C. Havermans and H. Robert (RBINS, INV. 132951) [extraction I2; Genbank nr, COI: KU870845, 28S: KU759622].&lt;/p&gt; &lt;p&gt; &lt;b&gt;Paratype&lt;/b&gt;&lt;/p&gt; &lt;p&gt; RV &lt;i&gt;Polarstern&lt;/i&gt; cruises:&lt;/p&gt; &lt;p&gt;SOUTHERN OCEAN: 1 juv., sex undetermined, cruise PS77, ANT-XXVII/3, CAMBIO, stn 248- 2, Larsen B, 65&deg;57.51ʹ S, 60&deg;28.15ʹ W to 65&deg;57.69ʹ S, 60&deg;28.30ʹ W, 196&ndash;202 m, Agassiz trawl and Rauschert dredge, 7 Mar. 2011, coll. C. Havermans and H. Robert (RBINS, INV. 122896).&lt;/p&gt; Description &lt;p&gt;ROSTRUM. In lateral view fairly short and narrow, reaching tip of article 1 of peduncle of antenna 1, weakly and regularly curved on anterior border, posterior border straight, tip very acute; in frontal view triangular: narrow, with straight converging borders, with tip blunt.&lt;/p&gt; &lt;p&gt;EYES. Large, broadly elliptic.&lt;/p&gt; &lt;p&gt;PEREION&ndash;PLEOSOME TOOTH PATTERN. Pereionites 1&ndash;7 totally smooth; pleonite 1 keeled along all its length, posteriorly terminated by tiny but distinct bump; pleonite 2 keeled with well developed acute posterodorsal tooth; pleonite 3 keeled with posterodorsal tip forming a distinct blunt process (shape: acute angle) distinctly projecting backwards.&lt;/p&gt; &lt;p&gt;COXAE 1&ndash;3. Tip acute.&lt;/p&gt; &lt;p&gt;COXA 4. Narrow; anterodorsal and anteroventral border forming a continuous curve without any trace of discontinuity (there is no distinct anterior corner), not curving significantly more ventrally; the coxa is not projecting forward; ventral corner forming an acute (nearly squared) angle of which the tip is blunt but not broadly rounded; posteroventral border distinctly concave; posterodorsal border 0.9 &times; as long as posteroventral border.&lt;/p&gt; &lt;p&gt;COXA 5. Very broad, posteroventral corner forming a blunt but distinct obtuse (nearly squared) angle.&lt;/p&gt; &lt;p&gt;COXA 6. Posterior border regularly rounded.&lt;/p&gt; &lt;p&gt;COXA 7. Posterior border straight; posteroventral corner forming a distinct obtuse angle.&lt;/p&gt; &lt;p&gt;EPIMERAL PLATES 1&ndash;3. Posteroventral angle: forming a squared angle in plate 1, produced into a tiny tooth in plate 2, produced into a small tooth in plate 3.&lt;/p&gt; &lt;p&gt;UROSOME TOOTH PATTERN. Urosomite 1 with distinct triangular dorsal process, anteriorly weakly concave, tip straight, posterior border nearly straight (inconspicuously concave); urosomite 3 with dorsolateral borders straight, with tip forming a squared angle.&lt;/p&gt; &lt;p&gt;TELSON. Cleft on 0.20; lobes with tips broad; notch broadly V-shaped.&lt;/p&gt; &lt;p&gt;GNATHOPODS 1&ndash;2. Carpus and propodus of normal slenderness; propodus not narrowing distally, and palm distinct but weak.&lt;/p&gt; &lt;p&gt;PEREIOPOD 5. Basis of normal width, with posteroproximal process reduced to low proximal dilatation in continuity with the more distal part of the posterior border, with posterodistal corner forming a long, narrowly triangular tooth projecting backwards; merus, carpus and propodus stout.&lt;/p&gt; &lt;p&gt;PEREIOPOD 6. Basis of normal width, with posteroproximal process reduced to low proximal dilatation in continuity with the more distal part of the posterior border, with posterior border distinctly diverging from anterior border, with posterodistal corner forming a triangular process (acute, nearly squared angle) weakly projecting backwards; merus, carpus and propodus stout.&lt;/p&gt; &lt;p&gt;PEREIOPOD 7. Basis broad; posterior border nearly straight, with weak but distinct concavity in distal 0.8, terminated into a tooth forming a squared angle.&lt;/p&gt; Body length &lt;p&gt;Up to 16 mm.&lt;/p&gt; Distribution &lt;p&gt;Western Weddell Sea: Larsen B, 196&ndash;202 m; probably eastern shelf of the Weddell Sea, 268&ndash;277 m (see remarks).&lt;/p&gt; Remarks &lt;p&gt; &lt;i&gt;Epimeria&lt;/i&gt; (&lt;i&gt;Subepimeria&lt;/i&gt;) &lt;i&gt;teres&lt;/i&gt; sp. nov. is morphologically very similar to &lt;i&gt;E.&lt;/i&gt; (&lt;i&gt;S.&lt;/i&gt;) &lt;i&gt;urvillei&lt;/i&gt; sp. nov., while genetic data (COI, 28S) Verheye et al. (2016a) suggests that they are different species (Fig. 342). In &lt;i&gt;E.&lt;/i&gt; (&lt;i&gt;S.&lt;/i&gt;) &lt;i&gt;teres&lt;/i&gt; sp. nov., the rostrum is a bit longer, the eyes slightly more rounded, coxa 4 a bit narrower, and the tip of the basis of pereiopod 7 more produced than in &lt;i&gt;E.&lt;/i&gt; (&lt;i&gt;S.&lt;/i&gt;) &lt;i&gt;urvillei&lt;/i&gt; sp. nov. It is likely that the &lsquo; &lt;i&gt;Epimeria&lt;/i&gt; aff. &lt;i&gt;puncticulata&lt;/i&gt; &rsquo; illustrated by Rauschert &amp; Arntz (2015) is &lt;i&gt;E.&lt;/i&gt; (&lt;i&gt;S.&lt;/i&gt;) &lt;i&gt;teres&lt;/i&gt; sp. nov., as it has a narrow coxa 4, a very strong posterodorsal protrusion on pleonite 3, a very strong dorsal protrusion on urosomite 1 and a posterodistal tooth on the basis of pereiopod 7. Rauschert &amp; Arntz (2015) did not give the collection details of their specimen, but this information was present in an early draft of their book made available to the authors. It is indicated that the specimen was collected during the cruise ANT-XXI (obviously ANT-XXI/2) at station 276 (i.e., 276-1 as there are no other sub-stations). The coordinates of this station are: 71&deg;06.44ʹ S, 11&deg;27.76ʹ W to 71&deg;06.64ʹ S, 11&deg;27.28ʹ W [eastern shelf of the Weddell Sea], 268&ndash; 277 m.&lt;/p&gt;Published as part of &lt;i&gt;d'Acoz, Cédric d'Udekem &amp; Verheye, Marie L., 2017, Epimeria of the Southern Ocean with notes on their relatives (Crustacea, Amphipoda, Eusiroidea), pp. 1-553 in European Journal of Taxonomy 359&lt;/i&gt; on pages 149-151, DOI: 10.5852/ejt.2017.359, &lt;a href="http://zenodo.org/record/3855694"&gt;http://zenodo.org/record/3855694&lt;/a&gt