In tadpoles that have a medial vent, the vent tube typically exits the abdominal cavity and extends posteriorly parallel with the ventral fin. In microhylids, it is not uncommon for the vent to exit the body cavity more dorsally; the vent tube extends ventrally in the anterior margin of the ventral fin and then empties by a ventrally facing aperture. The tadpoles of Calluella guttulata that were first examined shortly after they were preserved had the black tail margins similar to that of C. yunnanensis. Tadpoles of Calluella smithi (Haas and Das 2012) are similar in shape to those of C. guttulata, but lack the dark tail pigmentation.