Choco Vireo vs Long-tailed Sylph

Vireo masteri compared with Aglaiocercus kingii

Key Differences

• Choco Vireo is Endangered while Long-tailed Sylph is Least Concern.

Taxonomic Classification

Rank	Choco Vireo	Long-tailed Sylph
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class same	Aves (Birds)	Aves (Birds)
Order	Passeriformes (Songbirds)	Apodiformes (Apodiformes)
Family	Vireonidae	Trochilidae
Genus	Vireo	Aglaiocercus
Species	Vireo masteri	Aglaiocercus kingii

Evolutionary Relationship

Choco Vireo and Long-tailed Sylph share a common ancestor at the Class level: Aves. (Birds)

Conservation Status

Choco Vireo

EN — Endangered

Long-tailed Sylph

LC — Least Concern

Physical Characteristics

Attribute	Choco Vireo	Long-tailed Sylph
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Choco Vireo

Habitat

Found across multiple habitat types including tropical and subtropical dry broadleaf forests, flooded grasslands and savannas, and montane grasslands and shrublands, among 4 distinct biome types within the Neotropic biogeographic realm.

Range

Distributed across Colombia, Ecuador, and Norway. Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Long-tailed Sylph

Habitat

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

Range

Distributed across Colombia, Ecuador, Norway, and Venezuela.

Choco Vireo

The Choco Vireo (Vireo masteri) is a small, poorly known passerine in the family Vireonidae, with a highly restricted range in the western Andes foothills on the Pacific slope of Colombia and possibly adjacent Ecuador. It was described scientifically only in 1997, reflecting the challenges of survey work in the remote, wet, and botanically complex terrain of the Colombian Chocó. The Choco Vireo is a small greenish-yellow vireo with a distinctive facial pattern including a pale supercilium and dark eye-stripe. Like other vireos, it forages methodically through mid-canopy and sub-canopy foliage, gleaning caterpillars, beetles, and other invertebrates from leaves. Its song is a series of high, slurred phrases repeated with characteristic vireonid persistence. The species appears restricted to humid montane and foothill forest at elevations roughly between 800 and 1,800 metres — a zone severely impacted by the expansion of coca cultivation, illegal logging, and cattle ranching in the Colombian Pacific region. The IUCN classifies the Choco Vireo as Endangered given its extremely small and severely fragmented range and continued loss of suitable forest habitat. Very little is known about its population size, ecology, or breeding biology, making targeted survey and monitoring urgently needed.

Long-tailed Sylph

One of the most strikingly ornamented hummingbirds, male long-tailed sylphs have iridescent green plumage and dramatically elongated, ribbon-like outer tail feathers reaching up to 22 cm — over three times the body length. Found in Andean cloud forests of Colombia and Venezuela, they inhabit humid montane forest between 1,400–2,800 meters elevation. Males perform elaborate display flights to attract females. Their extravagant tails are a classic example of sexual selection via female preference.

Shared Countries

Both species can be found in 3 countries:

🇨🇴 Colombia 🇪🇨 Ecuador 🇳🇴 Norway