Key to Species of Hymenodora

Modified from Butler (1980), Chace (1986) and Wicksten (2002; 2011):

1 Telson terminating in elongate distally rounded spatulate endpiece laterally armed with spines.........................2

- Telson truncate distally................................................................................ 3

2. Carapace corrugated dorsally in gastric region; ocular peduncle short, nearly as long as broad at base; cornea reduced, and unpigmented...................................................................... Hymenodora chacei n. sp.

- Carapace not corrugated in gastric region; ocular peduncle about twice as long as broad at base; cornea faceted and pigmented......................................................... Hymenodora acanthitelsonis Wasmer, 1972

3. Rostrum short, reaching little beyond cornea of eye.......................................................... 4

- Rostrum longer, reaching at least as far as distal end of antennular peduncle......... Hymenodora frontalis Rathbun, 1902

4. Second maxilliped with podobranch; upper border of rostrum more or less gently concave from above orbital margin, lower border not markedly convex; no crescent-shaped sulcus in hepatic region of carapace.... Hymenodora gracilis, Smith, 1886

- Second maxilliped without podobranch; superior border of rostrum generally descending from high swollen anterior part of carapace, inferior border often convex; crescent-shaped sulcus present in hepatic region of carapace........................................................................................ Hymenodora glacialis (Buchholz, 1874)