''Scarthyla vigilans'' (Maracaibo Basin treefrog) is a species 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 ...

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 ...

. It is found in northern Colombia (Caribbean lowlands,

Magdalena Valley The Magdalena River Valley ( es, Valle del Río Magdalena) is a valley in Colombia located within the Colombian Andes. The valley is specifically situated between the Central and Eastern Ranges and crossed by the river of the same name, the Magda ...

, and eastern llanos), northern

Venezuela Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in th ...

(

Maracaibo Basin The Maracaibo Basin, also known as Lake Maracaibo natural region, Lake Maracaibo depression or Lake Maracaibo Lowlands, is a foreland basin and one of the eight natural regions of Venezuela, found in the northwestern corner of Venezuela in South A ...

Falcón ) , anthem = , image_map = Falcon in Venezuela.svg , map_alt = , map_caption = Location within Venezuela , pushpin_map = , pushpin_map_alt = , pushpin_mapsiz ...

, Coastal Range, high Llanos and

Orinoco Delta The Orinoco Delta is a vast river delta of the Orinoco River, located in eastern Venezuela. Location The Orinoco Delta is one of the eight natural regions of Venezuela. It covers the whole of Delta Amacuro State and a few square kilometers of ...

), and

Trinidad Trinidad is the larger and more populous of the two major islands of Trinidad and Tobago. The island lies off the northeastern coast of Venezuela and sits on the continental shelf of South America. It is often referred to as the southernmos ...

. Although generic allocation of this species has been controversial, molecular data have now confirmed its close relationship with '' Scarthyla goinorum'' and placement in that genus. Indeed, adults are very similar to ''Scarthyla goinorum''; however, the male advertisement call and

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 are clearly distinct.

Description

''Scarthyla vigilans'' are small frogs, with a maximum size of in snout–vent length. The body is elongate and slender. The head is as wide as the body and longer than it is wide. The snout is long and acuminate. The eyes are moderately large and protuberant. The tympanum is distinct although partly obscured by the diffuse supratympanic fold. The fingers and toes are slender and bear small round discs. The fingers lack webbing while the toes are webbed. Night-time coloration is lime green with indistinct stripes; the ventral parts are transparent. During the day, the coloration is more contrasting. Males have a single subgular

vocal sac The vocal sac is the flexible membrane of skin possessed by most male frogs and toads. The purpose of the vocal sac is usually as an amplification of their mating or advertisement call. The presence or development of the vocal sac is one way ...

. The male advertisement call resembles a cricket chirp (and can be mistaken as such) and has very low intensity. The tadpoles have short, globular body and moderately long tail. The maximum total length is .

Habitat and conservation

''Scarthyla vigilans'' occurs in open environments of lowlands, including flooded grasslands, degraded areas with low vegetation, and shallow standing water. Breeding takes place in standing water and swamps. Its maximum altitude is about above sea level, although most records are from lower elevations. It is a very common but nocturnal, small, and inconspicuous species. The call is relatively low and easily masked by other calling frogs. It is adaptable and not facing any known threats. It is present in some protected areas.

References

{{Taxonbar, from=Q1610368 vigilans Amphibians of Colombia Amphibians of Trinidad and Tobago Amphibians of Venezuela Amphibians described in 1971 Taxonomy articles created by Polbot