Aristias otway, Stoddart & Lowry, 2010

Stoddart, H. E. & Lowry, J. K., 2010, The family Aristiidae (Crustacea: Amphipoda: Lysianassoidea) in Australian waters, Zootaxa 2549 (1), pp. 31-53 : 41-42

publication ID	https://doi.org/ 10.11646/zootaxa.2634.1.5
DOI	https://doi.org/10.5281/zenodo.5309674
persistent identifier	https://treatment.plazi.org/id/215E983A-E84A-FFAC-FF46-FE1FFCC68E7C
treatment provided by	Felipe
scientific name	Aristias otway
status	sp. nov.

Treatment

Aristias otway View in CoL sp. nov.

( Figs 10–12)

Type material. HOLOTYPE, female with nonsetose oostegites, 2.8 mm, MV J61977 View Materials , 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 GoogleMaps . PARATYPES: 1 male, 2.8 mm, MV J59375 View Materials and 1 immature, MV J59376 View Materials , same data as holotype GoogleMaps ; 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 GoogleMaps .

Type locality. 25 km south of Cape Otway , Victoria, Australia, 39°07.6’S 143°25.0’E GoogleMaps 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.