The key uses external morphological characters visible without dissection. Diagnostic terms are highlighted. Click any species name for full description, photos, distribution and ecology.
Native species
- carapace with a single postorbital ridge without distal spine
- rostrum converging distally, smooth without a median carina, short apex
- antennal scale smooth, not denticulate
- carapace with a single postorbital ridge without distal spine
- rostrum converging distally, smooth without a median carina, short apex
- antennal scale denticulate
- carapace with two distinct postorbital ridges, second pair often distally blunt
- rostrum with almost parallel margins, prominent median carina, long apex
- carapace with two distinct postorbital ridges, with obvious distal spine
- long and narrow rostrum with almost parallel margins, prominent median carina, long apex
Non-native species
- carapace with a single postorbital ridge with obvious distal spine
- margins of rostrum almost parallel without median carina, long and acuminated apex
- carapace with a single postorbital ridge with distal spine
- elongated rostrum with smooth margins, median carina absent, triangular apex
