1. Lateral margin of carapace lamellar, intestinal region prominent, prominent basiolateral protuberances on fused male abdominal segment................ A. elata n. comb.
— Lateral margin of carapace rounded, intestinal region somewhat inflated, basiolateral regions of fused male abdominal segment slightly inflated.......................... 2
2. Dorsal surface of carapace closely set with rounded granules, subdistal denticle on fused male abdominal segment medially sulcate, lower margin of first and second pereiopods in male bearing a denticle, second pleopod sinuous, distally curved...................................................................................... A. elongata n. comb.
— Dorsal surface of carapace closely set with fine, flattened granules, subdistal denticle on fused male abdominal segment lozenge-shaped, lower margin of first and second pereiopods in male lacking denticle, second pleopod sinuous, distally coiled............................................................................................ A. nana n. comb.