''Megastomatohyla'' is a genus of

frog A frog is any member of a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-frog" ''Triadobatrachus'' is ...

s in the family

Hylidae Hylidae is a wide-ranging family of frogs commonly referred to as "tree frogs and their allies". However, the hylids include a diversity of frog species, many of which do not live in trees, but are terrestrial or semiaquatic. Taxonomy and ...

. They are

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

to the cloud forests of central

Veracruz Veracruz (), formally Veracruz de Ignacio de la Llave (), officially the Free and Sovereign State of Veracruz de Ignacio de la Llave ( es, Estado Libre y Soberano de Veracruz de Ignacio de la Llave), is one of the 31 states which, along with Me ...

and

Oaxaca Oaxaca ( , also , , from nci, Huāxyacac ), officially the Free and Sovereign State of Oaxaca ( es, Estado Libre y Soberano de Oaxaca), is one of the 32 states that compose the political divisions of Mexico, Federative Entities of Mexico. It is ...

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

. All are rare species with restricted distributions. The generic name is derived from Greek ''mega'' (="large") and stem of the genitive ''stomatos'' (="mouth"), referring to the enlarged oral disc of the

tadpole A tadpole is the larval stage in the biological life cycle of an amphibian. Most tadpoles are fully aquatic, though some species of amphibians have tadpoles that are terrestrial. Tadpoles have some fish-like features that may not be found ...

s, juxtaposed with ''

Hyla ''Hyla'' is a genus of frogs in the tree frog family Hylidae. As traditionally defined, it was a wastebasket genus with more than 300 species found in Europe, Asia, Africa, and across the Americas. After a major revision of the family most of th ...

'', the genus in which the four ''Megastomatohyla'' species were previously placed. Common name large-mouthed treefrogs has been coined for this genus.

Taxonomy and characteristics

''Megastomatohyla'' was erected in 2005 as a part of a major revision of the Hylidae and corresponds to the former "''Hyla mixomaculata'' group". The delineation was based on molecular data. The only tentative morphological

synapomorphy In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to hav ...

of the genus is the greatly enlarged oral disc of the tadpoles, which has 7–10 anterior rows and 10–11 posterior rows—in those species where this trait is known. ''Megastomatohyla'' are small stream-breeding frogs, reaching a maximum snout–vent length of about . Males do not

call Call or Calls may refer to: Arts, entertainment, and media Games * Call, a type of betting in poker * Call, in the game of contract bridge, a bid, pass, double, or redouble in the bidding stage Music and dance * Call (band), from Lahore, Paki ...

and lack vocal slits, which could also be a synapomorphy. Males also lack nuptial excrescences on the thumb. The tympanum is concealed. The fingers are no more than one-third webbed, while the toes are at least three-fourths webbed.

Species

The genus contains four recognized species:

References

{{Taxonbar, from=Q2319929 Hylinae Amphibian genera Fauna of the Sierra Madre de Oaxaca Endemic amphibians of Mexico Taxa named by Jonathan A. Campbell Taxa named by Darrel Frost