129 species in 2 genera
Commonly Called Fleshbelly Frogs, Brittle-Belly Frogs, Robber Frogs
Photo by Julian C. Lee
(Click for family gallery)
The family Craugastoridae consists of direct developing frogs, with a disjunct distribution; the genus Craugastor extends from the southwestern United States through Mexico and Central America and into northwestern South America, while the genus Haddadus is found in southeastern Brazil. The divergence is thought to have occurred between 31 and 59 million years ago, before the major Andean uplift. The organization of the family has a complicated history with some including Strabomantidae, Strabomantinae, Eleutherodactylidae, Ceuthomantinae or Holoadeninae with conflicting evidence for the superfamily of Brachycephaloidea. The sister group to Craugastoridae is Strabomantidae.
Members of this family range in size from 18 mm snout-vent length in female Craugastor pygmaeus to 110 mm in female Craugastor pelorus. Most species occur in the leaf litter of forest floors although some species occurs in more rocky outcrops (Craugastor augusti).
Several species of this group are believed extinct: Craugastor chrysozetetes from Honduras and Craugastor escoces from Costa Rica, among others which have not been seen in the wild for decades despite extensive field efforts.Written by AmphibiaWeb
Notable Family Characteristics
- Terrestrial, occurring in the leaf litter or along streams in forests, with one species known from rocky cliffs (Craugastor augusti)
- Axillary amplexus
- Direct development, with eggs deposited terrestrially or arboreally
- Many species with some form of parental care (Savage 2002)
- Morphological characters include: 1) Finger I longer than Finger II, in most species; 2) unwebbed fingers; 3) lack of prominent external glands on the body; 4) digit tips expanded into pads having circummarginal grooves; 5) inner and outer metatarsal tubercles present; 6) tympanic membrane and annulus usually distinct (Hedges et al. 2008).
- Osteological characters include: 1) cartilaginous sternum; 2) vertebral shield not present; 3) transverse processes of posterior presacral vertebrae not broadly expanded; 4) widely spaced cervical cotyles; 5) eight presacral vertebrae, with Presacrals I and II not fused; 6) omosternum present; 7) sacral diapophyses rounded or barely dilated; 8) maxillary arch usually dentate, with blunt, pedicellate teeth; 9) alary processes of premaxillae are broad at base, usually directed dorsally or posterodorsally; 10) palatal shelf of premaxilla usually broad, indented or not; 11) pars facialis of maxilla usually deep, not exostosed; 12) palatal shelf of maxilla moderately broad, may bear pterygoid process or not; 13) maxillary arch complete; maxillae taper posteriorly; quadratojugal slender; 14) nasals usually large with broad median contact; not usually in contact with maxillae or pterygoids; not in contact with frontoparietals; 15) frontoparietal fontanelle usually absent; 16) frontoparietals usually not exostosed; cranial crests present or not; 17) cranial elements not co-ossified with overlying skin; 18) frontoparietals fused with prootics or not; 19) temporal arcade absent; 20) carotid artery passing dorsal to cranial elements; 21) zygomatic ramus of squamosal broad to slender, usually not in contact with maxilla; 22) squamosal-maxilla angle 44-67° ; 23) columella present; fenestra ovalis directed laterally; 24) broad neopalatines; 25) sphenethmoid entire; 26) anterior ramus of parasphenoid not keeled; 27) parasphenoid alae at right angle to axis of skull or deflected posteriorly, usually not overlapped by pterygoids; 28) pterygoid without ventral flange; 29) occipital condyles widely separated medially; 30) odontoids lacking; 31) T-shaped terminal phalanges; 32) three phalanges in Finger IV; 33) Toe I fully developed and free; 34) mandibular ramus of trigeminal nerve passing lateral to the m. adductor mandibulae ("S" condition) in Haddadus, passing medially ("E" condition) in Craugastor (Hedges et al. 2008).
- Distribution limited to southwestern United States through Mexico and Central America and into northwestern South America (Craugastor) as well as southeastern Brazil (Haddadus)
Cartography Credit: Zoe Yoo, UC Berkeley
Range maps sources: AmphibiaWeb, UC Berkeley, and IUCN RedList
Hedges, S. B., Duellman, W. E., and Heinicke, M. P. (2008). New World direct-developing frogs (Anura: Terrarana): Molecular phylogeny, classification, biogeography, and conservation. Zootaxa 1737: 1-182.
Pough, F. H., R. M. Andrews, M. L. Crump, A. H. Savitzky, K. D. Wells, and M. C. Brandley. 2015. Herpetology. Fourth Edition. Massachusetts: Sinauer.
Savage, J. (2002). The Amphibians and Reptiles of Costa Rica. University of Chicago Press, Chicago and London.
Vitt, L. J., and J. P. Caldwell. 2013. Herpetology. An Introductory Biology of Amphibians and Reptiles. Fourth Edition. Amsterdam: Elsevier.
Genus Craugastor (126 species)
Genus Haddadus (3 species)
Haddadus aramunha no account photos no sound/video Haddadus binotatus no account photos sound/video Haddadus plicifer no account no photos no sound/video
Citation: AmphibiaWeb: Information on amphibian biology and conservation. [web application]. Berkeley, California: AmphibiaWeb. Available: https://amphibiaweb.org/. (Accessed:
AmphibiaWeb's policy on data use.