Pareidae
Formosa Slug Snake
HarmlessPareas formosensis






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.
Keep learning
- What to Do If You Find a SnakeFound a snake at home or on a trail? Here is how to stay calm, give it space, identify it safely, and know when to call a professional.
- Venomous vs Nonvenomous: How to Tell the DifferenceThe folk rules for telling venomous snakes apart, where each one fails, and why location-based identification beats guessing by sight.
- What Is a Snake? Anatomy and the BasicsA clear overview of what makes a snake a snake: limbless body plan, anatomy, evolution from lizards, species diversity, and why they are ectothermic.
- How to Keep Snakes Out of Your Yard and HomeA practical guide to keeping snakes out of your yard and home using habitat changes that work, plus what to skip and what to do if one shows up.
Distribution from GBIF & iNaturalist. Venom status per CDC. Background: Wikipedia. Informational only. Never handle a snake to identify it.







