Key to subfamilies of Chasmocarcinidae

1. Antennule with peduncle not particularly enlarged although incapable of being folded into fossa (e.g., Fig. 21 A); dorsal anten-

nular flagellum with elongated aesthetascs (e.g., Fig. 21 A). Carapace subtrapezoidal or subtriangular (e.g., Fig. 2); buccal cavern quadrate or rectangular (e.g., Figs. 21 B, 27A)........................................................... 2 - Antennule with greatly enlarged, swollen peduncle (e.g., Fig. 27 B); dorsal antennular flagellum with large, wide aesthetascs (e.g., Fig. 19 A‒C, G). Carapace quadrate or rectangular (e.g., Figs. 19 B, 20E); buccal cavern conspicuously arched, sunken (e.g., Figs. 27 C, 103D)..................................................................... Megaesthesiinae

2. Rounded or quadrate antennular peduncle (Fig. 22 A); basal antennular article swollen so that antennular flagellum cannot fold into fossa (Fig. 22 A). Vulva typically not conspicuously large, with thin margins (e.g., Figs. 89 B). Indirect development; marine................................................................................ Chasmocarcininae

- Rectangular antennular peduncle (Fig. 94 E, J); basal antennular article not swollen so that antennular flagellum can partially fold into fossa (Fig. 94 E, J). Vulva conspicuously large, with thick margins (e.g., Fig. 99 D, F, H). Direct development (see Davie & Guinot 1996: fig. 2). Freshwater, including inland caves.................................... Trogloplacinae