most tadpoles of closely related taxa, but they have a distinct terminal oral discs. The existence of a dextral vent tube is a common trait for the clade consisting of Edalorhina, Engystomops, and Physalaemus. Within the clade, Edalorhina is unique for having two lingual papillae bordered around the anteroventrally directed mouth, a filiform median ridge, and a lack of buccal roof papillae. The total head-tail length ranges from 14 mm to 29.7 mm. The body length is around 5 mm and is wider than it is deep. The tadpoles have small eyes that are widely separated at each side of the front of the body. The nostril position has been described dorsolaterally and anterolaterally. The oral disc has also been described both as terminal and ventral. These contradictory descriptions might reflect the intraspecific diversity of the tadpoles. E. perezi tadpoles have a posteriorly directed sinistral spiracle and a short anal tube. The dorsal fin only grows on the tail. The general color of the tadpole is pale brown with streaks of darker brown shades dorsally and laterally. Taxonomy Perez’s snouted frog, Edalorhina perezi, is in the genus Edalorhina and family Leptodactylidae. The only two species in this genus are E. perezi and E. nasuta. Previous studies addressing phylogeny have mostly focusing on morphological, behavioral and karyotypical differences. An earlier morphological and behavioral study considered Edalorhina to be most closely related to the families Lithodytes and Physalaemus as all of them construct foam nests. In a later cytogenetics study, the analysis of all 22 chromosomes of this frog also suggested the close relationship between Edalorhina and Physalaemus, while Pleurodema is relatively less related to Edalorhina. However, the precise phylogenetic relationships of Edalorhina are still under a debate. Geographical variation Studies have shown that there are large variations in Perez’s snouted frog’s morphology. An early study conducted by Dunn in 1949 examined 52 specimens and revealed dissimilarity in vomerine teeth and dorsal skin structure. The study classified this species into three morphs: perezi, plicifrons and buckleyi. The Perezi type has a dermal ridge between the eyes and vomerine teeth, but it lacks longitudinal warts on the back. Plicifrons, on the other hand, has longitudinal warts, but lacks vomerine teeth and dermal ridge. Buckleyi looks similar to Plicifrons, but it has vomerine teeth. Dunn also noticed that certain appearances are more common in distinct areas of the species' range. For example, 86.6% of