Craugastor talamancae (Dunn 1931)

Faunal biodiversity is high within the range of Craugastor talamancae; details are presented herein for one example ecoregion of the range, the Panamanian dry forests, a region significant since it is a biological corridor from the montane forests to the coastal mangroves. Faunal species richness is high in the Panamanian dry forests, as in much of Mesoamerica, with a total of 519 recorded vertebrates alone within the Panamanian dry forests. (World Wildlife Fund) Special status reptiles in the Panamanian dry forests include the American crocodile (Crocodylus acutus), the Lower Risk/Near Threatened brown wood turtle (Rhinoclemmys annulata), the Lower Risk/Near Threatened common caiman (Caiman crocodilus), the Lower Risk/Near Threatened common slider (Trachemys scripta), and the Critically Endangered leatherback turtle (Dermochelys coriacea). There are two special status amphibian in the ecoregion: the Critically endangered plantation Glass Frog (Hyalinobatrachium colymbiphyllum) and the Vulnerable Camron mushroom-tongued salamander (Bolitoglossa lignicolor).

Threatened mammals found in the Panamanian dry forests are the: Endangered Central American spider monkey (Ateles geoffroyi), the Vulnerable giant anteater (Myrmecophaga tridactyla), the Near Threatened Handley’s tailless bat (Anoura cultrata), the Vulnerable lemurine night monkey (Aotus lemurinus), the Near Threatened margay (Leopardus wiedii), the Near Threatened yellow isthmus rat (Isthmomys flavidus), the Near Threatened white-lipped peccary (Tayassu pecari), and the Near Threatened spectral bat (Vampyrum spectrum). There are two special status bird species occurring in the ecoregion: the Endangered great green macaw (Ara ambiguus) and the Near Threatened olive-sided flycatcher (Contopus cooperi).

This frog is relatively small in stature, exhibiting pronounced sexual dimorphism with females achieving a snout to vent length of 45-50 millimeters and males 28-30 millimeters. Chief diagnostics are that all limbs are elongated, with feet displaying moderate webbing. The dorsal coloration is usually brown, and typically a dark bar is exhibited between the eyes, with additional barring on each limb. Each eye exhibits an iris that is gold in coloration above.

For C. talamancae, the concealed surfaces include rear thigh surfaces that may be yellowish or brownish, and having prominent infusion of red or purple. (Köhler. 2001) Juveniles of the species have a prominent white colored lip line. (Savage. 2002)

Craugastor talamancae is currently known from the Atlantic versant of Mesoamerica in eastern Nicaragua through the lower elevation moist forests to the south through Costa Rica, and on the Pacific coast in the lowland moist forests, the low elevation Panamanian dry forests and coastal mangroves. Most distribution maps illustrate occurrence across the Continental Divide of Panama, but the population is more likely disjunctive, since that montane area is generally considered higher than the altitudinal niche of this species. The estimated elevation bracket of taxon occurrence lies between 15 and 646 meters above mean sea level. (Savage. 2002)

This frog is considered terrestrial in habit, dwelling in the humid lowland forests, dry forests and mangroves on both the Pacific and Atlantic sides of central Mesoamerica.

The climate within the modest elevations of this taxon is warm, with an average annual temperature of about 15 to 22 degrees Celsius. Annual rainfall is around 1500 to 5000 millimeters, with the higher precipitation levels occurring on the Caribbean side of the species distribution.

An ancestor of genus Craugastor entered Central America from northern South America in the early Paleocene by way of a hypothesized Proto-Antillean landbridge. (Crawford & Smith. 2005) Present genus Craugastor distribution extends from the southwestern USA southward to Mexico and Central America and northwestern South America, while the sister genus Haddadus occurs disjunctively in southeastern Brazil. The divergence between these only two genera in the family Craugastoridae is deemed to have transpired between 31 and 59 million years ago, prior to the major Andean uplift. (Hedges et al. 2005) Craugastor represents a monophyletic group, as first established by Crawford and Smith. Most speciation within genus Craugastor occurred within the Eocene.

Although there is no detailed long term population study data for the species, the recent trend in species population is that of decline according to the IUCN. This species is rather commonly observed in the Atlantic lowlands of Costa Rica, as well as in the lowlands and premontane forests in Panama; however, the occurrence in southeast Nicaragua is considered rare. (Sunyer et al. 2009) Moreover, the population at La Selva, Costa Rica appears to have experienced declines as reported by the IUCN. (Solis et al. 2011) The overarching reason for this population loss is pressure on the species due to deforestation and subsequent habitat loss and fragmentation. Loss of cover from reduction in standing leaf litter is also an associated proximate cause of species decline noted at La Selva; (Solis et al. 2011) such leaf litter reduction can be caused by thinning of trees or by reduction in precipitation levels over a sustained multi-decadal period. An additional reason for the population decline is chytridiomycosis.

The ecological importance of the Panamanian dry forests stems from its critical location as a biological corridor for seasonal migration of species moving from the higher elevation moist forests to the coastal mangroves, or simply as a gene pool connector for species that can reside in the moist forests as well as the mangroves. In the latter case, populations of some taxa such as the Almirante robber frog (Craugastor talamancae) are effectively isolated by the degradation of the Panamanian dry forests. Most of the ecologically useful fraction of this corridor has been effectively severed by human activity and land cover changes exacted to accommodate the burgeoning human population

Agricultural land conversion is an ongoing threat, as the worldwide human population explosion is placing an ever-growing demand for food crops, and grazing of domestic livestock; the resultant economic pressure for further agricultural land conversion at these easily accessible altitudes. Furthermore, agricultural conversion and human settlement uses compete for surface water resources, further degrading terrestrial habitat.

Craugastor talamancae is a species of frog in the family Craugastoridae. It is found in the Atlantic versant of Panama, Costa Rica, and southeastern Nicaragua. Common name Almirante robber frog has been proposed for it.