Grass Coqui

Grass Coqui, Shrub Coqui (Eng.), Coqui de las Yerbas (Sp.), Eleutherodactylus brittoni (Sci.), Native, Puerto Rico.

Photo Father Alejandro Sanchez. Information compiled by Alan Mowbray, Interpretive Media Writer, EYNF/LEF

General Information

Coqui frogs are of the Amphibia Class in the Order Anura. They are in the Brachycephalidae Family of the Genus Eleutherodactylus. There are 16 species of Eleutherodactylus frogs on the island of Puerto Rico. Eleutherodactylus frogs have individual (non-webbed) fingers and toes. They do not pass through a tadpole stage and thus do not require water to reproduce. Instead, after fertilization by the male, eggs are laid by the female in humid areas. When the eggs hatch, a fully-formed froglet (a tiny replica of the adult frog) emerges. In Puerto Rico all Eleutherodactylus frogs are generally called coqui frogs, although the males of only two of the sixteen known species on the island emit the plaintive ko-kee call.

Description

The Grass Coqui (E. brittoni) is a small species measuring approximately 0.6 inches (16 millimeters) in snout-to-vent length. It has a narrow black streak with a fine, light line above it, which begins at the tip of the snout and continues on each side to a point almost halfway along the flank. There is typically a small, round spot in the middle of the back below the shoulder. The area near the cloaca (vent) is black or dark brown.

Habits

E. brittoni inhabits only humid grassy areas and fern thickets. The Grass Coqui call is a quick trill composed of one to five notes (Click here to hear E. brittoni call). The sound is quite loud, given the small size of the Grass Coqui. If the listener is not familiar with the species the sound can often be confused with that made by crickets. Eggs are laid in humid areas, usually in leaf litter shelter. Like all other Eleutherodactylus species, the Grass Coqui is primarily an insectivore, having a preference for dipterans (flies and mosquitoes), arachnids, crustaceans, centipedes, millipedes and mollusks are also included in its diet.

Habitat

The Grass Coqui species is widespread in the interior uplands of Puerto Rico, showing a preference for open meadows and grassy areas. Although considered a lowland species, it has been recorded at locations varying from sea level up to 3,280 feet (1,000 meters) in elevation.

Where to look for this animal in the EYNF

In grassy areas adjoining the El Portal and Big Tree nature trails.