Formosa Slug Snake

Formosa Slug Snake

Pareas formosensis

Silhouette: Marius Burger (photograph) · PhyloPic

Least ConcernNear ThreatenedVulnerableEndangeredCritically Endangered
Daily sighting probability ~40% · Likely
at Cuc Phuong National Park
13 Verified sightings at Cuc Phuong National Park From 2019 to 2026
13 Verified sightings across 1 park From 2019 to 2026
August Best month highest sighting rate
☀️ Diurnal When it's spotted during daytime hours (6am–6pm)

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. 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.

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... Wikipedia →

Global Distribution

Warmer areas are where this animal is recorded most often.

Parks Where Found

# Park Country Daily sighting probability
1 Cuc Phuong National Park 🇻🇳 Vietnam
~40%

More parks will be added in future updates.

Quick answers

What are the chances of seeing a Formosa Slug Snake in Cuc Phuong National Park?

About 40% of wildlife watchers report a Formosa Slug Snake sighting in Cuc Phuong National Park, based on 13 verified sightings from GBIF citizen-science data.

When is the best time to see Formosa Slug Snake in Cuc Phuong National Park?

August has the highest sighting rate for Formosa Slug Snake in Cuc Phuong National Park in our monthly data.

← Back to Cuc Phuong National Park