Titicaca Water Frog

A medium-sized telmatobiid frog typically measuring 3.8–5.5 inches (9.7–14 cm) in length. Body is moderately robust with relatively short, weak hind limbs poorly adapted for terrestrial locomotion. Most distinctive feature is the presence of copious loose, wrinkled skin folds and flaps covering the dorsal and lateral surfaces of the body, head, and limbs—a unique adaptation for aquatic respiration in the cold, oxygen-poor waters of Lake Titicaca. Dorsal coloration is typically dark brown to blackish, often with a flattened appearance. The head is relatively broad and flattened. Eyes are small and dorsolateral in position. Tympanum is absent or indistinct. Fingers are unwebbed; toes are fully webbed. The ventral surface is lighter, typically tan to yellowish-brown. Skin texture is smooth to granular. This species is almost entirely aquatic, spending its entire life in the cold waters of Lake Titicaca at elevations around 12,500 feet (3,810 m), rarely venturing onto land. The abundant skin folds greatly increase surface area for cutaneous respiration, allowing the frog to extract oxygen directly from water—a critical adaptation in a high-altitude lake with seasonal oxygen depletion. Diet consists of small aquatic invertebrates, including insect larvae, crustaceans, and other small organisms found in the lake bottom.

Call is unknown or not well-documented; this species produces little vocalization and lacks a prominent tympanum typical of most anurans, consistent with its highly specialized aquatic existence.

Similar species: Andean Water Frog (Telmatobius marmoratus) has less extensive skin folding and occurs in cooler mountain streams rather than open lake environments; Lake Junín Frog (Telmatobius macrostomus) is restricted to a different Andean lake and lacks the pronounced cutaneous folds; Titicaca Weasel Frog (Telmatobius simonbolivari) is smaller and inhabits shallow wetland margins rather than deep lake waters.