Cochran Frog vs European otter

Nymphargus cochranae compared with Lutra lutra

Taxonomic Classification

Rank	Cochran Frog	European otter
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class	Amphibia (Amphibians)	Mammalia (Mammals)
Order	Anura (Frogs & Toads)	Carnivora (Carnivorans)
Family	Centrolenidae	Mustelidae (Weasels & Otters)
Genus	Nymphargus	Lutra (Otters)
Species	Nymphargus cochranae	Lutra lutra

Evolutionary Relationship

Cochran Frog and European otter share a common ancestor at the Phylum level: Chordata. (Chordates)

Conservation Status

Cochran Frog

VU — Vulnerable

European otter

VU — Vulnerable

Trend: Stable →

Physical Characteristics

Attribute	Cochran Frog	European otter
Diet	—	Carnivore
Average Lifespan	—	10 years
Average Length	—	1.0 m
Average Weight	—	10.0 kg

Habitat & Geographic Range

Cochran Frog

Habitat

Typically found in freshwater habitats, moist forests, and wetlands.

Range

Found in Colombia. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

European otter

Habitat

Typically found in diverse ecosystems where prey species are available.

Range

Found across Europe (6 countries). Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Cochran Frog

The Cochran frog (Nymphargus cochranae) is a small glass frog in the family Centrolenidae, native to the cloud forests of the western and central Andes in Colombia. Like other centrolenid frogs, it is characterised by semi-transparent or translucent ventral skin through which internal organs — including the heart, liver, and digestive tract — are visible, a feature that gives the family its common name. The species inhabits humid montane rainforest along streams at elevations typically between 1,500 and 2,800 metres, where males call from vegetation overhanging fast-flowing streams to attract females. Eggs are deposited in gelatinous masses on leaves or rocks above the water; upon hatching, tadpoles drop into the stream below and develop in the current-swept environment. Nymphargus cochranae is classified as Vulnerable by the IUCN, primarily due to ongoing deforestation and degradation of cloud forest habitats driven by agricultural expansion, cattle ranching, and coca cultivation across its Colombian Andean range. Glass frogs are additionally sensitive to stream water quality, making them useful bioindicators of watershed health. The species was named in honour of the eminent American herpetologist Doris Mable Cochran of the Smithsonian Institution, who made foundational contributions to Central and South American amphibian taxonomy in the mid-twentieth century. Continued habitat protection and reforestation efforts are critical for its long-term survival.

European otter

Sleek semi-aquatic mustelid found along clean rivers, streams, and coastlines across Europe and Asia. European otters can reach 1.3 meters in length and are highly skilled fish hunters, using sensitive whiskers to detect prey movements. Requiring unpolluted water with abundant fish, they are an indicator species for freshwater ecosystem health. Once nearly extinct in Western Europe from hunting and pollution, populations have recovered significantly following water quality improvements.