The vane of the ventral fin adjacent to the body of these microhylids is an uncommon trait that also occurs in Xenopus (Pipidae) and some phyllomedusine hylids that feed while stationary in midwater. The vane was not noticed when the Glyphoglossus tadpoles were collected and is not visible in the photograph of a live tadpole. Increased opacity in preservative and eventual staining revealed this odd morphology. The Glyphoglossus tadpoles were collected near the bottom in about 1 m of muddy water.