Key to the genera of Milnesiidae

1 Bucco-pharyngeal apparatus with rigid tube (Fig. 5 B,C)............................................................................................. 2

- Bucco-pharyngeal apparatus subdivided into a short anterior buccal tube and a flexible posterior pharyngeal tube with spiral thickening (Fig. 5 D,E) .............................................................................................................. Limmenius

2 Buccal tube long; mouth at anterior of a protrusible snout (Fig. 5 C)........................................................ Milnesioides

- Buccal tube shorter; snout absent (Fig. 5 B) ................................................................................................. Milnesium