Key for Pacific Atyoida species

1.1 P1 and P2 polymorphic atyoid, caridinoid and ortmannoid (indifferently male or female); Posterior margin of telson armed with 2-7 distinct fixed teeth................................................................. A. bisulcata (Hawaii)

1.2 P1 and P2 dimorphic atyoid (female) and caridinoid (male); Posterior margin of telson armed with indistinct fixed teeth.....2

2.1 From Vanuatu to Marquesas archipelago; living specimens with blue-black patterns of different shapes; telson with 1 to 5 pairs of dorsal spinules, often not in pairs); its posterior margin with 4 to 9 plumose intermediate setae distinctly longer than lateral ones; Uropodal diaeresis with 15-22 spinules........................................................ A. pilipes

2.2 From Rarotonga, French Polynesia except Marquesas archipelago; living specimens with dark longitudinal stripes; telson with 2 to 3 pairs of dorsal spinules, often in pairs; its posterior margin 6 to 13 plumose intermediate setae distinctly longer than lateral ones; Uropodal diaeresis with 11-18 spinules................................................. A. tahitensis