Complex-toothed Flying Squirrel vs European otter

Trogopterus xanthipes compared with Lutra lutra

Key Differences

• Complex-toothed Flying Squirrel is Near Threatened while European otter is Vulnerable.

Taxonomic Classification

Rank	Complex-toothed Flying Squirrel	European otter
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class same	Mammalia (Mammals)	Mammalia (Mammals)
Order	Rodentia (Rodents)	Carnivora (Carnivorans)
Family	Sciuridae (Squirrels)	Mustelidae (Weasels & Otters)
Genus	Trogopterus	Lutra (Otters)
Species	Trogopterus xanthipes	Lutra lutra

Evolutionary Relationship

Complex-toothed Flying Squirrel and European otter share a common ancestor at the Class level: Mammalia. (Mammals)

Conservation Status

Complex-toothed Flying Squirrel

NT — Near Threatened

European otter

VU — Vulnerable

Trend: Stable →

Physical Characteristics

Attribute	Complex-toothed Flying Squirrel	European otter
Diet	—	Carnivore
Average Lifespan	—	10 years
Average Length	—	1.0 m
Average Weight	—	10.0 kg

Habitat & Geographic Range

Complex-toothed Flying Squirrel

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

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.

Complex-toothed Flying Squirrel

<em>Trogopterus xanthipes</em>, the complex-toothed flying squirrel, is a medium-sized gliding rodent in the family Pteromyidae endemic to China, where it inhabits montane broadleaf and mixed forests at elevations typically between 1,000 and 2,700 metres in provinces including Sichuan, Yunnan, Guizhou, Hubei, and neighbouring regions. This species is the sole member of the genus Trogopterus and is distinguished by complex tooth morphology compared to other flying squirrels. Like all flying squirrels, it possesses a patagium — a gliding membrane stretching between fore and hind limbs — that enables it to glide between trees rather than undertake powered flight. The complex-toothed flying squirrel is nocturnal and arboreal, spending its days sheltering in tree hollows and foraging at night for leaves, bark, seeds, and fungi. Its faeces, known as Wuflingzhi, have been used in traditional Chinese medicine for centuries, leading to trapping pressure in parts of its range. The IUCN classifies this species as Near Threatened, reflecting population decline driven by overhunting for medicinal use and ongoing habitat loss from logging and agricultural encroachment in montane forests. Biological traits including average body mass, lifespan, litter size, and home range are partially documented but detailed population estimates are limited. Conservation measures include legal protections under Chinese wildlife law.

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.