Long-tailed Sylph vs Williamson's Mouse-deer

Aglaiocercus kingii compared with Tragulus williamsoni

Key Differences

• Long-tailed Sylph is Least Concern while Williamson's Mouse-deer is Data Deficient.

Taxonomic Classification

Rank	Long-tailed Sylph	Williamson's Mouse-deer
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class	Aves (Birds)	Mammalia (Mammals)
Order	Apodiformes (Apodiformes)	Artiodactyla (Even-toed Ungulates)
Family	Trochilidae	Tragulidae
Genus	Aglaiocercus	Tragulus
Species	Aglaiocercus kingii	Tragulus williamsoni

Evolutionary Relationship

Long-tailed Sylph and Williamson's Mouse-deer share a common ancestor at the Phylum level: Chordata. (Chordates)

Conservation Status

Long-tailed Sylph

LC — Least Concern

Williamson's Mouse-deer

DD — Data Deficient

Physical Characteristics

Attribute	Long-tailed Sylph	Williamson's Mouse-deer
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Long-tailed Sylph

Habitat

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

Range

Distributed across Colombia, Ecuador, Norway, and Venezuela.

Williamson's Mouse-deer

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

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.