Long-tailed Sylph vs Shelled Slug

Aglaiocercus kingii compared with Testacella haliotidea

Key Differences

• Long-tailed Sylph is Least Concern while Shelled Slug is Data Deficient.

Taxonomic Classification

Rank	Long-tailed Sylph	Shelled Slug
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Chordata (Chordates)	Mollusca (Mollusks)
Class	Aves (Birds)	Gastropoda (Gastropoda)
Order	Apodiformes (Apodiformes)	Stylommatophora (Stylommatophora)
Family	Trochilidae	Testacellidae
Genus	Aglaiocercus	Testacella
Species	Aglaiocercus kingii	Testacella haliotidea

Evolutionary Relationship

Long-tailed Sylph and Shelled Slug share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Long-tailed Sylph

LC — Least Concern

Shelled Slug

DD — Data Deficient

Physical Characteristics

Attribute	Long-tailed Sylph	Shelled Slug
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.

Shelled Slug

Habitat

Typically found in terrestrial and aquatic habitats including forests and freshwater.

Range

Widely distributed across Europe (9 countries), North America (United States), and Oceania and the Pacific (New Zealand).

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.