The shell is minute, Neritoid or Crepidula-like, with a small depressed lateral spire, apparently dextral, composed of about 1

The aperture is very large, oblique, transversely oval, the peristome continuous and free, thin.

The soft parts are sinistral, externally Limnaeoid, with large black eyes near the inner bases of the short blunt cylindric tentacles.

The deck of Amphigyra is present at all stages of growth observed, in young as well as mature shells.

In Gundlachia no septum is developed until a period of hybernation or aestivation is reached.