This article is about a Brazilian genus of frogs sometimes known as "river frogs". For other genera/species sharing this common name, see River frog (disambiguation).
Thoropa is a genus of frogs in the family Cycloramphidae.[1][2] They are endemic to eastern and southeastern Brazil. They are sometimes known as river frogs.[1]
Thoropa are associated with rocks and have cryptic coloration. Their size ranges from small to medium, 28–102 mm (1.1–4.0 in) in snout–vent length.[3] They occur at elevations up to 1,500 m (4,900 ft) above sea level;[3]Thoropa miliaris and Thoropa taophora can even live on rocky marine shores, foraging in the intertidal zone.[4][5] Male Thoropa are associated with wet rock faces, whereas the females seem to range more widely.[6]
In species where reproduction is known, males are territorial—suitable wet rock faces are a scarce resource. Furthermore, mature male Thoropa feature characteristic clusters of dark spines on the inner portions of the hand. It appears that these are associated with male-male combat, probably in conjunction with territorial disputes. Scratch marks in males, but not in females, support this interpretation.[6]
The eggs are laid on rocks with a thin layer of water. Tadpoles are semiterrestrial and have a depressed shape, long tail, and bulging eyes.[3]
Male T. taophora frogs mate exclusively and repeatedly with two females per season in a polygynous system in which the semiterrestrial tadpoles from both females share the same freshwater seep.[7] The females have a dominance hierarchy, and the males mate more with the dominant female.[7]
^ abcdFrost, Darrel R. (2018). "Thoropa Cope, 1865". Amphibian Species of the World: an Online Reference. Version 6.0. American Museum of Natural History. Retrieved 12 October 2018.
^ ab"Cycloramphidae". AmphibiaWeb: Information on amphibian biology and conservation. [web application]. Berkeley, California: AmphibiaWeb. 2018. Retrieved 12 October 2018.
^Abe, A. S. & Bicudo, J. E. P. W. (1991). "Adaptations to salinity and osmoregulation in the frog Thoropa miliaris (Amphibia, Leptodactylidae)". Zoologischer Anzeiger. 227: 313–318. hdl:11449/117830.