Epimeriidae Boeck 1871

Family and sub-family key to Antarctic and sub-Antarctic Epimeriidae and their putative relatives

This key includes the Epimeriidae s. str. and putatively related families and subfamilies of Eusiroidea present in the Southern Ocean.

1. Posterior border of basis of pereiopod 7 not produced into an immense median acute process pointing backwards ……….………………………………………………………………………..2

– Posterior border of basis of pereiopod 7 produced into an immense median acute process pointing backwards [all pereionites and pleosomites with mid-dorsal crest and with transverse carinae and grooves; rostrum absent; telson blunt-tipped, not cleft] …………………………………………… …………………………………………………………… Dikwidae Coleman & J.L. Barnard, 1991

2. Article 1 of peduncle of antenna 1 not produced into a large and broad lobe forming a hood above articles 2–3 ………………………………………………………………………………………….3

– Article 1 of peduncle of antenna 1 produced into a large and broad lobe forming a hood above articles 2–3 ………………………………………………………………….. Vicmusiidae Just, 1990

3. Surface of pereion segments just above connection with coxa either smooth or with very small tooth, or surface of pereion (and most parts of body and appendages) homogeneously and densely covered by medium-sized styliform teeth (giving a hedgehog facies to the animal) ………………………..4

– Surface of pereion segments just above connection with coxa with a large or huge process pointing laterally [telson entire] …………………... Acanthonotozomellidae Coleman & J.L. Barnard, 1991

4. Coxa 1 narrow or fairly narrow; eyes bulging (rounded, elliptic or reniform), remaining distinct in alcohol; mandible with molar process present; maxilla 2 plates not broadened; teguments strongly to weakly calcified; rostrum well-developed to vestigial ………………….... Epimeriidae Boeck, 1871

– Coxa 1 broad; eyes not bulging, of various shapes, often disappearing in alcohol; mandible with molar process absent; maxilla 2 with plates broadened; teguments weakly calcified; rostrum always vestigial: Stilipedidae Holmes, 1908 ………………………………………………………………5

5. Outer plate of maxilliped well-developed but distinctly shorter than palp; pleosomites without posterodorsal tooth ………………………………………………………………………………….6

– Outer plate of maxilliped immensely developed, overreaching palp; pleosomites with or without posterodorsal tooth ……………………………………… Alexandrellinae Holman & Watling, 1983

6. Coxae 1–3 longer than coxa 4 ……………………..……………………. Stilipedinae Holmes, 1908

– Coxae 1–3 not longer than coxa 4 ……………………………………………. Astyrinae Pirlot, 1934