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Pareidae

Formosa Slug Snake

Harmless

Pareas formosensis

Formosa Slug Snake
Pareas formosensis, © Dmitry Ivanov
Formosa Slug SnakeFormosa Slug SnakeFormosa Slug SnakeFormosa Slug SnakeFormosa Slug Snake

6 photographs of the Formosa Slug Snake. © Dmitry Ivanov.

The Formosa Slug Snake (Pareas formosensis) is a non-venomous snake in the Pareidae family, recorded in 6 countries.

Family
Pareidae

About the Formosa Slug Snake

Formosa slug snake or Taiwan slug snake (Pareas formosensis) is a species of non-venomous snake in the family Pareatidae. It is endemic to Taiwan.

Taxonomy

It has been suggested that Pareas chinensis should be treated as a synonym of P. formosensis, but recent genetic research does not support this: P. formosensis does not appear closely related to P. chinensis but is instead a sister species to P. hamptoni. The delineation of these species is not clear. In future, P. formosensis might become a subspecies of P. hamptoni, or some snakes from the mainland might be classified as P. formosensis.

Further studies have shown that Pareas komaii is a valid species, instead of being a synonym of P. formosensis. The study also described a new species, Pareas atayal, that have been confused with P. formosensis. Thus, three Pareas species occur in Taiwan.

Description

The Formosa slug snake is a small snake with total length up to 70 cm (28 in). These snakes are widespread in mountainous, moist forests. Formosa slug snakes are nocturnal and feed on land snails and slugs. Female snakes produce a clutch of 2–9 eggs; the hatchlings measure about 15 cm (5.9 in) in total length.

P. formosensis is readily distinguished from P. komaii and P. atayal by its red iris and totally smooth dorsal scales.

Distribution

The Formosa slug snake occurs throughout the mountain regions of Taiwan, except for the north-eastern tip of the island.

Adapted from Wikipedia, available under CC BY-SA.

Frequently asked: Formosa Slug Snake

Is the Formosa Slug Snake venomous?
No. The Formosa Slug Snake (Pareas formosensis) is non-venomous and is not considered dangerous to humans. Like most snakes, it will retreat rather than bite when given the chance.
Is the Formosa Slug Snake poisonous?
Snakes are venomous, not poisonous. "Poisonous" means harmful to eat or touch; "venomous" means injecting toxins through a bite. The Formosa Slug Snake is neither poisonous nor venomous.
Is the Formosa Slug Snake dangerous?
The Formosa Slug Snake is not dangerous to humans. It has no medically significant venom and bites only defensively if cornered or handled.
Where does the Formosa Slug Snake live?
The Formosa Slug Snake has verified records in 6 countries, including Chinese Taipei, China, Viet Nam. See the distribution section below for its full range.

Where it is found

More Pareidae snakes

Classification

How scientists group this snake, from the broadest category down to the exact species. Each step narrows to its closest relatives.

OrderThe broad group of scaled reptiles: all snakes and lizards
Squamata
FamilyA group of related snakes that share key traits
Pareidae
GenusA close-knit group of very similar species
Pareas
SpeciesThis exact snake, named in the two-part scientific name
Pareas formosensis

Keep learning

Distribution from GBIF & iNaturalist. Venom status per CDC. Background: Wikipedia. Informational only. Never handle a snake to identify it.