Overview
The Lake Oku Clawed Frog (Xenopus longipes) is a genetically extraordinary and critically imperiled amphibian restricted entirely to the waters of a single volcanic crater lake in the Cameroon Highlands. Discovered by herpetologists in 1979 in Lake Oku at an elevation of over 7,200 feet, this tiny, fully aquatic pipid frog is famous throughout evolutionary genetics for being a natural dodecaploid or octoploid organism, possessing multiple duplicated complete chromosome sets. Teetering on the brink of extinction due to sudden mass die-offs, this gentle water frog is the focus of urgent international aquatic conservation interventions.
Biology and Physical Characteristics
The physical structure of Xenopus longipes is adapted exclusively for life submerged underwater. The frog possesses a dorsoventrally flattened body with a small, rounded head, lidless upward-directed eyes, and no external tongue or eardrums. Its hind limbs are disproportionately long and muscular, equipped with immense, fully webbed toes terminating in three sharp, black keratinized claws used to tear food and stir up lakebed sediment. The skin is smooth, slimy, and covered in sensitive lateral-line stitches that detect minute water vibrations. Its coloration consists of a pale amber to olive dorsum speckled with dark brown irregular spots, offset by an immaculate butter-yellow to cream ventral belly.
Behavior and Ecology
The Lake Oku clawed frog is completely aquatic, never leaving the lake water throughout its entire lifecycle. It spends daytime hours resting among submerged weed beds or gliding gracefully through the water column using simultaneous breaststroke kicks of its powerful hind legs. When feeding, it approaches aquatic insect larvae or worms, opening its wide mouth to generate an explosive vacuum that sucks prey whole into its gullet, using its clawed forelimbs to manipulate larger food items. Reproduction occurs in spring, with females depositing hundreds of individual gelatinous eggs attached to submerged water plants.
Conservation and Human Impact
Xenopus longipes is categorized as Critically Endangered by the IUCN because its entire global wild population is confined to a single lake measuring less than 2.5 square kilometers. Between 2006 and 2010, the species suffered catastrophic mass mortality events linked to outbreaks of the deadly amphibian chytrid fungus (Batrachochytrium dendrobatidis) alongside unidentified parasitic infections. The species also faces potential risks from illegal fish introductions, agricultural runoff from hillside farms, and tourist pollution. International zoos, including the Zoological Society of London (ZSL), have established biosecure captive assurance colonies to safeguard the species against sudden total extinction.
Interesting Factoid
Xenopus longipes is one of the few vertebrates on Earth with an octoploid genome, possessing eight full sets of chromosomes (108 chromosomes in total)—the result of ancient hybridization events that duplicated its entire genetic code.
Last updated: October 2026