Gastrophryne, the narrowmouth toads (also American narrowmouth toads, North American narrow-mouthed toads), is a genus of microhylid frogs found in the Americas between Honduras and southern United States.[1] Its name means ‘belly-toad’, referring to its large belly, from the Ancient Greek (Greek, Ancient (to 1453);: [[wikt:γαστήρ|γαστήρ]], ‘belly, stomach’) and (Greek, Ancient (to 1453);: φρύνη, ‘toad’).[2]
Gastrophryne is closely related to Hypopachus. Some species that were earlier placed in Gastrophryne were more closely related to Hypopachus, rendering the genus paraphyletic.[1] This has been rectified by moving some species (Gastrophryne usta and Gastrophryne pictiventris) to Hypopachus.[3]
Gastrophryne frogs were the first species to be recognized to be experiencing speciation by reinforcement and lead to the coining of the term reinforcement by W. Frank Blair in 1955;[4] a concept proposed by Theodosius Dobzhansky decades earlier.
The currently recognized species are:[1]