Aristias Boeck, 1871

Kilgallen, Niamh M., 2010, A new Antarctic species of Aristias Boeck (Crustacea, Amphipoda, Aristiidae), with remarks on the genus in Antarctica, Zootaxa 2426, pp. 43-53 : 44

Genus Aristias Boeck, 1871

Aristias Boeck, 1871: 106 . — Stebbing, 1906: 49. — Hurley, 1963: 40, 41 (key). —J.L. Barnard, 1969: 324. — Lincoln, 1979: 60. — Barnard & Karaman, 1991: 465. — Lowry & Stoddart, 1997: 14.

Type species. Anonyx tumidus Krøyer, 1846 , by monotypy.

Diagnosis (modified after Lowry & Stoddart 1997). Head deeper than long. Epistome and upper lip fused. Mandibles usually asymmetrical, left straight, minutely serrate, right straight or slightly convex, smooth; left lacinia mobilis minute or absent; accessory setal row well developed or absent, if present with more than 5 accessory setae; molar a small, weakly setose flap or absent. Maxilla 1 inner plate strongly setose, usually with more than 2 pappose setae, outer plate broad, setal teeth in a modified 7/4 arrangement; palp 2-articulate. Maxilliped outer plate without apical robust setae; palp well-developed, 4-articulate. Gnathopod 1 simple to parachelate, coxa vestigial, posterior margin of propodus serrate. Gnathopod 2 coxa well developed. Pereopods 3–7 simple, propodus usually with a distal spur. Pereopod 4 deeper than wide with weak posteroventral lobe. Pereopod 5 coxa with well-developed posteroventral lobe. Gills from gnathopod 2 to pereopod 6, not pleated. Telson moderately to deeply cleft.

Species composition and distributions. Aristias includes 28 species worldwide. Antarctic and sub- Antarctic: A. antarcticus Walker, 1906 (Cape Adare; Commonwealth Bay; Davis Sea, Kerguelen Islands; Magellan area; Ross Sea; South Georgia; South Shetland Islands; Weddell Sea); A. collinus K.H. Barnard, 1932 (South Shetland Islands; Weddell Sea); A. excavatus sp. nov. (Ross Sea). Atlantic Ocean and Arctic: A. bicornuta Ortiz, Lalana & Varela, 2007 ( Cuba) ; A. captiva Lowry & Stoddart, 1997 (Gulf of Mexico); A. commensalis Bonnier, 1896 (Bay of Biscay); A. falcatus Stephensen, 1923 (S.W. of the Faeroe Islands); A. megalops G.O. Sars, 1895 ( Norway) ; A. microps G.O. Sars, 1895 ( Norway) ; A. neglectus Hansen, 1888 (widespread along European coasts from the Adriatic to Norway); A. topsenti Chevreux, 1900 (Newfoundland) ; A. tumidus (Krøyer, 1846) (Arctic Ocean) . Indian Ocean: A. madagascarensis Ledoyer, 1972 ( Madagascar) ; A. stenopodus Ledoyer, 1986 ( Madagascar) ; A. symbioticus K.H. Barnard, 1916 ( South Africa; Madagascar). Pacific Ocean: A. adrogans J.L. Barnard, 1964 (Alaska) ; A. coriolis Lowry & Stoddart, 1993 ( Philippines) ; A. curtipes Gurjanova, 1962 (Pacific Ocean, west of Japan); A. expers J.L. Barnard, 1967 (Baja California); A. japonicus Gurjanova, 1962 (Sea of Japan); A. nonspinus Hirayama, 1985 ( Japan) ; A. pacificus Schellenberg, 1936 ( Japan; Vancouver Island); A. spinipes Gurjanova, 1962 (east of Kamchatka Peninsula); A. thio Lowry & Stoddart, 1994 ( New Caledonia); A. tropicus Schellenberg, 1938 ( Bismarck Archipelago, Papua New Guinea); A. uokonia Lowry & Stoddart, 1994 ( New Caledonia); A. veleronis Hurley, 1963 (Puget Sound) ; A. verdensis Lowry & Stoddart, 1993 ( Philippines) .

Known fauna associations. A. excavatus sp. nov. is associated with the sponge Myxodoryx hanitschi ; A. bicornuta associated with the hexactinellid sponge Lefroyella crispa ; A. commensalis associated with a sponge and an asteroid; A. neglectus recorded associations include the brachiopod Terebratulina caputserpentis , the anemone Bolocera tuediae , sponges Geodia spp ., and ascidians; A. topsenti , associated with a species of sponge; A. tumidus , associated with the tunicate Molgula retortiformis ; A. symbioticus , associated with an ophiuroid and a sponge; A. pacificus , associated with the ascidian Ascidia paratropa .