1 No spines on the frontal and lateral lobes of the carapace……… A. chauvini Reyss, 1975
– Carapace with spines on the frontal and lateral lobes……………………………………2
2 Pseudorostrum moderately arched, peronites 1–5 each with one pair of strong dorsal spines, pleonites 1–2 spinose…………………………………… A. japonica Gamô, 2001
– Pseudorostrum not arched, no dorsal spines on pereon or pleon…… A. borealis sp. nov.