S. contumelia has a snout–vent length of about 8–9 mm (0.31–0.35 in), making it one of the world's smallest frogs, and several others in the genus are only slightly larger.

[9] There was a temporary impasse, wherein the Amphibian Species of the World database continued to adopt the single-genus taxonomy, and as a result, so too did the IUCN Red List of Endangered Species and other online databases (e.g. iNaturalist) that draw from that resource.

[12][13] In March 2019, a new genus, Mini, was described for the miniaturised frogs previously confused with Stumpffia that are more closely related to Plethodontohyla.

[14] Evidence in this study, as well as that presented in a paper by Na Tu et al. in 2018,[13] helped to clarify the taxonomic situation, and the Amphibian Species of the World database reverted to treating Rhombophryne, Anilany, and Stumpffia as valid genera.

[15] There are over 40 currently recognised species:[1][2][16][17] The taxon Stumpffia helenae'' Vallan, 2000 was transferred to Anilany[7] and therefore does not appear on this list.