Kergueleniidae, Lowry & Stoddart, 2010

Lowry, J. K. & Stoddart, H. E., 2010, Kergueleniidae fam. nov. (Crustacea: Amphipoda: Lysianassoidea) in Australian waters, Zootaxa 2564 (1), pp. 1-30 : 2

Kergueleniidae fam. nov.

Diagnostic description. Head exposed, slightly longer than deep. Antennae calceoli absent. Antenna 1 with callynophore in male; accessory flagellum article 1 not forming a cap. Antenna 2 peduncular article 3 without distal hook. Epistome and upper lip fused. Mouthpart bundle subquadrate. Mandible incisors vestigial or absent; left lacinia mobilis peg-like or absent, right lacinia mobilis absent; accessory setal row absent; molar vestigial or absent; palp inserted distally to extremely distally. Maxilla 1 inner plate with 2 or less apical setae; outer plate with 2 to 6 setal-teeth; palp large, 2-articulate, with or without apical robust setae, without subterminal lateral notch. Maxilla 2 inner plate significantly shorter than outer plate, without oblique row of facial setae. Maxilliped inner plate small; outer plate small, about as long as palp article 1, with medial and apical setae reduced or absent; palp 4-articulate, articles 3 and 4 long, slender.

Gnathopod 1 simple; coxa large, about as long as coxa 2; merus and carpus not rotated; ischium short, long or very long; carpus and propodus long, slender; dactylus straight or slightly curved, becoming filiform. Gnathopod 2 coxa large, subequal in size to coxa 3; carpus rectolinear or rectangular, with palmate setae; propodus rectangular, with palmate setae; dactylus minute. Pereopods all simple; distal spurs absent. Pereopod 4 coxa with very well developed posteroventral lobe. Pereopod 5 coxa with posteroventral lobe. Pereopod 6 coxa posterior lobe absent.

Uropod 2 inner ramus without constriction. Uropod 3 biramous, uniramous or rami absent. Telson entire.

Type genus. Kerguelenia Stebbing, 1888 .

Generic composition. Clepidecrella J.L. Barnard, 1962 ; Kerguelenia Stebbing, 1888 .

Remarks. Kergueleniids have lost many of the morphological markers that would indicate relationships to other lysianassoid families, but the group has some morphological similarities to endevourids and lysianassines. Kergueleniids differ most obviously from endevourids in having simple third pereopods. Kergueleniids may be most similar to lysianassines. Both have simple first gnathopods, large first coxae and a well developed posteroventral lobe on coxa 4. Kergueleniids differ from lysianassines in the extremely reduced (in both number and size) setal-teeth on maxilla 1 and in the extremely reduced plates on the maxilliped. Kergueleniids differ from taxa such as Lepidepecreella Schellenberg, 1926 and Izinkala Griffiths, 1977 , which also have very reduced mouthparts, in having coxae 1 to 4 well developed.