Boiga ceylonensis
Silhouette: Alex Slavenko · PhyloPic
In 3 days ~50% in a week ~80%
Boiga ceylonensis (Sri Lanka cat snake) is a species of rear-fanged, mildly venomous, nocturnal, arboreal colubrid snake endemic to Sri Lanka. This is a thin-bodied, elongate, slim, tree snake. Taxonomic features: Dorsal Scales in 19 rows, oblique; scales along the vertebral row much enlarged, and at mid body nearly as broad as long. Ventrals scales 217–237; the anals are undivided, subcaudals 95–109. The colour is brown or greyish above, with a series of blackish transverse cross bands; nape with a blackish blotch, or three blackish longitudinal streaks, or a transverse bar; a more or less distinct brown crown marking on top of head and a thick streak from the eye to the angle of the mouth; lower parts yellowish, dotted with brown, usually with a lateral series of small brown dots. They are about 4 feet long from tip to tip with the tail 10 inches.
It is an endemic species to Sri Lanka. Previously believed to occur in the Western Ghats of India, but was falsified by recent studies. This snake frequently ventures into human dwellings in search of prey such as geckos. It has a somewhat aggressive disposition and... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Sinharaja Forest Reserve | 🇱🇰 Sri Lanka |
More parks will be added in future updates.
Possible
About 20% of wildlife watchers report a Sri Lanka Cat Snake sighting in Sinharaja Forest Reserve on a given day, based on 12 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 18th most-seen of the 32 reptiles we can rate there. Over three days the chance rises to about 50%, and over a week to about 80%, if each day is a fresh chance.
July and August
In those months about 40% of wildlife watchers report a Sri Lanka Cat Snake in Sinharaja Forest Reserve on a given day, against under 5% in October and November, the lowest months.
Between 8 and 11 pm
Across all the parks we cover, that three-hour window holds the most Sri Lanka Cat Snake sightings with a recorded time, and about 7 in 10 of them come between 6 pm and 6 am: it is seen both by day and at night.
Only Sinharaja Forest Reserve, in our data
Sinharaja Forest Reserve is the only park on Wallace's Line with enough records to rate Sri Lanka Cat Snake sightings: about 20% of wildlife watchers there report one on a given day.
Same genus: Boiga
The closest relatives of the Sri Lanka Cat Snake that you can see in Sinharaja Forest Reserve (genus Boiga, Australasian Cat Snakes) are Beddome's Cat Snake (about 20%) and Barnes' Cat Snake (about 20%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Sri Lanka Cat Snake is recorded against all the reptiles logged in Sinharaja Forest Reserve (12 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
