Xenocheira Haswell, 1879

Hughes, Lauren Elizabeth, 2017, Review of Xenocheira Haswell, 1879 (Crustacea: Amphipoda: Aoridae), Records of the Australian Museum 69 (4), pp. 223-236 : 224-225

Xenocheira Haswell, 1879

Xenocheira Haswell, 1879: 272 . — Haswell, 1885: 105. — Stebbing, 1906: 624. — Moore, 1988: 706. — Myers, 1988: 191. —Barnard & Karaman, 1991: 240–241, fiGs 45E, 46E. —Lowry & Stoddart, 2003: 73 (catalogue).

Generic diagnosis. Sternal processes absent. Mandibular molar triturative, palp article 3 longer than 2, posterodistal margin straight, with setae of several lengths. Maxilliped basal endiTe anTeriOr marGin wiThOUT winG-like flanGes. Gnathopod 1 merus short; carpus shorter than propodus. Male gnathopod 1 propodus enlarged. Female gnathopod 1 simple to weakly subchelate. Male and female gnathopod 2 carpUs anTeriOr marGin wiTh flanGe, wiTh line Of lOnG

Included species. Xenocheira fasciata Haswell, 1879 ; X. longisetosa Ren, 2006 ; X. pirloti Moore, 1988 and X. xandrothrix sp. nov.

Remarks. Haswell’s original description of Xenocheira was of a female specimen only, collected in Port Jackson, New SOUTh Wales. MOOre (1988) was The firsT TO describe a male specimen of Xenocheira using material collected from Tasmania. This important contribution established that Xenocheira males are sexually dimorphic.

Xenocheira is close to Bemlos Shoemaker, 1925 and Autonoe , which are all sexually dimorphic genera where the propodus of gnathopod 1 is larger in males. Xenocheira and Bemlos can be separated from Autonoe by the carpus of gnathopod 1 being shorter than the propodus in males. Xenocheira differs frOm Bemlos in the presence of an anterior carpal flanGe lined wiTh seTae On GnaThOpOd 2 in bOTh males and females.

Xenocheira spp. are similar to Autonoe seurati Chevreux, 1907 which alsO has a flanGe and seTae, wiTh A. seurati being the only Autonoe species with this character state. Xenocheira can be separated from all Autonoe species by the mandibular palp article 3 straight posterodistal margin (versus concave); the gnathopod 1 carpus which is shorter than the propodus (versus subequal) and the uropod 3 rami with long robust and slender setae (versus robust setae only).

Key to males of Xenocheira Haswell, 1879 species 1 Gnathopod 1 propodus palm weakly obtuse ............................................................................. 2

—— Gnathopod 1 propodus palm transverse to subacute ................................................................. 3 2 Gnathopod 1 dactylus posterior margin smooth ................................. X. fasciata Haswell, 1879

—— Gnathopod 1 dactylus posterior margin with proximal hump ................ X. xandrothrix sp. nov.

3 Gnathopods 1 and 2 basis anterior margin without rows of slender setae ........................................................................................... X. pirloti Moore, 1988 .

—— Gnathopods 1 and 2 basis anterior margin with rows of slender setae ..................................................................................................... X. longisetosa Ren, 2006