The family Aristiidae (Crustacea: Amphipoda: Lysianassoidea) in Australian waters Author Stoddart, H. E. helen.stoddart@austmus.gov.au Author Lowry, J. K. text Zootaxa 2010 2010-07-26 2549 1 31 53 https://biotaxa.org/Zootaxa/article/view/zootaxa.2634.1.5 journal article 10.11646/zootaxa.2634.1.5 1175-5326 Aristias otway sp. nov. ( Figs 10–12 ) Type material. HOLOTYPE , female with nonsetose oostegites, 2.8 mm , MV J61977 , 25 km south of Cape Otway , Victoria , Australia , 39°07.6’S 143°25.0’E to 39°08.3’S 143°20.6’E , 55–84 m , fine sand, otter trawl, 31 January 1981 , M. Gomon et al ., FRV Hai Kung , stn BSS 119 . PARATYPES : 1 male , 2.8 mm , MV J59375 and 1 immature , MV J59376 , same data as holotype ; 1 female , AM P.81146, 44 km south-west of Cape Otway , Victoria , Australia , 39°06.3’S 142°55.6’E , 81 m , medium sand, 21 November 1981 , R . Wilson, RV Tangaroa , stn BSS-192 . FIGURE 10. Aristias otway sp. nov. Paratype, male, 2.8 mm, MV J59375 . Type locality. 25 km south of Cape Otway , Victoria , Australia , 39°07.6’S 143°25.0’E to 39°08.3’S 143°20.6’E , 55–84 m depth. Etymology. The species is named for its type locality. Diagnostic description. Head lateral cephalic lobe broadly triangular, apically rounded; eyes well developed, oval. Antenna 1 accessory flagellum 2-articulate. Antenna 2 calceoli not present in male. Epistome and upper lip with central notch . Mandible lacinia mobilis present on left mandible; molar absent. Maxilla 1 inner plate with 3 pappose setae along inner margin; outer plate with 7 setal-teeth in a 5/2 arrangement, with no cusps . Maxilliped palp 4-articulate, palp article 1 with lateral and medial margins about same length. Gnathopod 1 parachelate; carpus shorter than propodus, without posterodistal lobe; propodus posterior margin dentate, with 2 robust setae along posterior margin. Gnathopod 2 carpus longer than propodus. Pereopods 5–7 propodus with anterodistal spur. Pereopod 5 coxa posterior lobe deeper than anterior lobe, long, triangular; basis greatly expanded posteriorly, with posteroventral lobe. Pereopod 6 coxa posterior lobe deeper than anterior lobe, long, triangular; basis greatly expanded posteriorly, with posteroventral lobe. Pereopod 7 basis moderately expanded posteriorly, posterior margin evenly curved, with posteroventral lobe, posteroventral corner rounded. Epimeron 3 posterior margin smooth , posteroventral corner subacute . Urosomite 1 with an anterodorsal depression, without a dorsodistal boss. Urosomite 3 without dorsolateral flanges. Uropod 3 rami without robust setae; inner ramus longer than article 1 of outer ramus. Telson as long as broad, moderately cleft , without mid-dorsal robust setae, lateral margins straight, uniformly tapering distally, without robust setae on lateral margins, with 1 apical robust seta on each lobe. Remarks. Aristias otway is the only species known to have no sculpturing on the setal-teeth of maxilla 1. Based on the 5/2 setal-tooth arrangement of maxilla 1, the anterodistal spur on each of pereopods 5 to 7, the subacute posteroventral corner of epimeron 3 and the moderately cleft telson A. otway appears to be most similar to A. madagascarensis . The two species can be distinguished by the serrate posterior margin of epimera 2 and 3 and by the rounded telsonic lobes in A. madagascarensis . Distribution. South-eastern Australia in 55–84 m depth.