Arcovomer passarellii

Arcovomer passarellii (common name: Passarelli's frog) is a species of frog in the family Microhylidae. It is monotypic within the genus Arcovomer. It is endemic to southeastern Brazil and found in Espírito Santo, Rio de Janeiro, and São Paulo states. Frogs from Espírito Santo may represent another, undescribed species. The name honours Antonio Passarelli who collected the holotype. Arcovomer passarellii is a small, slender-bodied frog. The male is about 16–20 mm (0.63–0.79 in) in snout–vent length, and the female 22–26 mm (0.87–1.02 in). Its body is brown above with a distinct irregular dark pattern running the whole length of the animal. Male frogs call after sunset. The advertisement call is a sharp, short whistle. When disturbed, these frogs may jump and then assume a stiff-leg posture, possibly as a means to avoid detection by predators relying on their sight. This species inhabits lowland primary and secondary forests. It is a ground-dwelling frog that breeds in temporary pools. Although it is a common species, it is declining in abundance, probably because of habitat loss.