Cerro Munchique Marsupial Frog

Gastrotheca trachyceps is a marsupial frog with snout-vent lengths (SVL) up to 50.0mm in males and 67.9 mm in females. Their heads are characterized as slightly wider than long with a bluntly round snout from the dorsal view and truncate snout from the profile. This species has an interorbital distance that is twice the width of the eyelid, and an eye diameter that is approximately equal to the distance between the eye and the nostril. Gastrotheca trachyceps have long tibias that measure approximately half the SVL and long feet that are just slightly shorter than the tibias. The skin of G. trachyceps is smooth on the dorsum but co-ossified with the head. Relative finger lengths are 1 = 2 < 4

Gastrotheca trachyceps occurs within the Northwestern Andean montane forests ecoregion. This species is currently known solely from the region of the type locality, Cerro Munchique on the western slopes of the Cordillera Occidental, in Cauca Department, Colombia. The estimated elevation range of the species lies between 2170 - 2540 m. All known occurrences are within the Parque Nacional Natural Munchique (Acosta-Galvis 2000; Castro and Lynch 2004). It is possible that this species range extends beyond the type locality, however detailed surveys for this species have not been performed. Additionally, based upon altitude preferences and the limited extent of preferential habitat, it is unlikely that the G. trachyceps’ total area extent exceeds 5000 km2 (Castro and Lynch 2004).This frog is frequently found upon shrub or tree vegetation, most often in subtropical or tropical moist montane forests as well as sub-tropical or tropical high-altitude paramo (Duellman 1987). Gastrotheca trachyceps most commonly occurs in forest interiors or forest edges, in forest understory or middle-tier vertical location under the canopy. The species has both terrestrial and arboreal traits. Densities are greatest near forest streams; moreover, G. trachyceps may also be found on shrubs in paramo type habitat as long as bromeliads are present, especially in proximity to surface water sources. The species is commonly found hiding in bromeliads that are in turn situated on shrubs or trees (Castro and Lynch 2004).

Genus Gastrotheca contain most of the marsupial frogs, which are characterized by the presence of a dorsal brood pouch in females. Eggs may be fertilized upon the lower back of the female, and then inserted into the brood pouch. After fertilization, eggs stay in contact with the female vascular tissue, which tissue provides the eggs with an oxygen supply. As with other marsupial frogs, the essential element of reproduction is direct development, with each egg retained in the female pouch female until the offspring is hatched. After developing to the tadpole stage in the female pouch, the tadpoles are deposited in ponds or stream pools (del Pino et al 1975).

Although there is no detailed long-term population study data for G. trachyceps, the species population is thought to be in decline due to deforestation and subsequent habitat loss and fragmentation for timber and agricultural development. While much of G. trachyceps habitat is under protection as a national park, there are limited resources for enforcement of protections. There are currently no specific conservation measures for this species (Castro and Lynch 2004).