Austromaera, Lowry & Springthorpe, 2005

Lowry, JK & Springthorpe, RT, 2005, New and Little-known Melitid Amphipods from Australian Waters (Crustacea: Amphipoda: Melitidae), Records of the Australian Museum 57, pp. 237-302 : 241

Austromaera n.gen.

Type species. Maera mastersii Haswell, 1879a .

Diagnosis. Head with anteroventral slit; eye ovate. Antenna 1 accessory flagellum short, significantly less than half length of primary flagellum. Mandible palp article 1 not produced distally; article 3 short, tapering distally; article 2 longer than article 3. Maxilla 1 inner plate with mainly apical setae. Gnathopod 1 coxa anteroventral corner produced, acute. Gnathopod 2 significantly enlarged in male and female; left and right gnathopods symmetrical in male (right slightly bigger than left); palm acute in male and female, male both propodi with well defined corner (greater than 90°), female both propodi with well defined corner (greater than 90°); dactylus with 1 or 2 setae on anterior margin. Pereopods 5–7 dactyli simple. Epimeron 2 posteroventral corner with 1 small spine. Epimeron 3 posterior margin smooth. Uropod 3 rami about 2× peduncle, distally subacute, without apical robust setae; outer ramus 1- articulate. Telson deeply cleft, lobes apically subacute, with robust setae on inner margins, without robust setae on outer margins, without apical robust setae.

Etymology. A combination of the Latin word auster, meaning southern, with the Latin stem Maera .

Species composition. Austromaera mastersii (Haswell, 1879a) .

Remarks. Austromaera is part of the large Maera group, in which gnathopod 2 is symmetrical and significantly enlarged in males and females, the palms are acute with well defined corners and the rami of uropod 3 are distally acute or subacute. The main defining characters of the genus are: the weakly produced first article of the mandibular palp and the distally acute margins of the rami of the third uropods. Austromaera is the only member of the Maera complex with such strongly setose inner margins on the telson. It is excluded from Maera and Miramaera because of its ovate eyes, its short accessory flagellum and its weakly produced first mandibular palp article. It is excluded from Maera and Lupimaera because of its sparsely setose gnathopod 2 dactylus. Austromaera occurs in the Maera group, but appears to be most similar to the Indian Ocean species of Zygomaera that apparently have symmetrical second gnathopods. The main difference between these taxa is the telson that is emarginate in the Indian Ocean species. Currently Austromaera is confined to Australian waters.

Distribution. Australia.