Cochran Frog vs Cock-tailed Tyrant

Nymphargus cochranae compared with Alectrurus tricolor

Taxonomic Classification

Rank	Cochran Frog	Cock-tailed Tyrant
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class	Amphibia (Amphibians)	Aves (Birds)
Order	Anura (Frogs & Toads)	Passeriformes (Songbirds)
Family	Centrolenidae	Tyrannidae
Genus	Nymphargus	Alectrurus
Species	Nymphargus cochranae	Alectrurus tricolor

Evolutionary Relationship

Cochran Frog and Cock-tailed Tyrant share a common ancestor at the Phylum level: Chordata. (Chordates)

Conservation Status

Cochran Frog

VU — Vulnerable

Cock-tailed Tyrant

VU — Vulnerable

Physical Characteristics

Attribute	Cochran Frog	Cock-tailed Tyrant
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

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.

Cock-tailed Tyrant

Habitat

Typically found in various aerial, terrestrial, and aquatic environments.

Range

Found in Norway. 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.

Cock-tailed Tyrant

The cock-tailed tyrant (Alectrurus tricolor) is a striking and unusual flycatcher in the family Tyrannidae, named for the remarkable elongated, spatula-shaped outer tail feathers of the male, which can exceed the body length and are displayed during aerial courtship flights over open grasslands. The species inhabits wet and seasonally flooded grasslands, cerrado savanna, and campos in the interior of South America, including central Brazil, eastern Bolivia, Paraguay, and northeastern Argentina — not Norway, as erroneous database entries suggest. Males combine conspicuous black, white, and rufous plumage with their extraordinary tail streamers in an elaborate display to attract females on leks; females are cryptically streaked brown. The cock-tailed tyrant is a ground- and low-vegetation forager, preying on insects and other small invertebrates gleaned from grass stems and caught in aerial sallies. The species is classified as Vulnerable by the IUCN due to extensive and continuing conversion and degradation of its native Neotropical grassland habitat through intensive soy and sugarcane agriculture, cattle ranching, fire management changes, and drainage of seasonally flooded grasslands. Populations have declined significantly across much of its range, particularly in Brazil and Paraguay. The species is a flagship for threatened grassland conservation in South America, where relatively little protection has historically been directed at open-country habitats compared to forest ecosystems.