Nycticebus bengalensis
Silhouette: Mareike C. Janiak · PhyloPic
In 3 days ~40% in a week ~70%
The Bengal slow loris (Nycticebus bengalensis) or northern slow loris is a strepsirrhine primate and a species of slow loris native to the Bangladesh, Northeast India, Cambodia, Laos, Burma, Vietnam, southern China, and Thailand. Its geographic range is larger than that of any other slow loris species. Considered a subspecies of the Sunda slow loris (N. coucang) until 2001, phylogenetic analysis suggests that the Bengal slow loris is most closely related to the Sunda slow loris. However, some individuals in both species have mitochondrial DNA sequences that resemble those of the other species, due to introgressive hybridization. It is the largest species of slow loris, measuring 26 to 38 cm (10 to 15 in) from head to tail and weighing between 1 and 2.1 kg (2.2 and 4.6 lb). Like other slow lorises, it has a wet nose (rhinarium), a round head, flat face, large eyes, small ears, a vestigial tail, and dense, woolly fur. The toxin it secretes from its brachial gland (a scent gland in its arm) differs chemically from that of other slow loris species and may be used to communicate information about sex, age, health, and social status.
The Bengal slow loris is nocturnal and arboreal, occurring in both evergreen and deciduous forests. It prefers rainforests with dense canopies, and its presence in its native habitat indicates a healthy ecosystem. It is a seed disperser and pollinator, as well as a prey item for carnivores. Its diet primarily consists of fruit, but also includes insects, tree gum, snails, and small vertebrates. In winter, it relies on plant exudates, such as sap and tree gum. The species lives in small family groups, marks its territory with urine, and sleeps during the day by curling up in dense vegetation or in tree holes. It is not a seasonal breeder, reproducing once every 12–18 months and usually giving birth to a single offspring. For the first three months, mothers carry their offspring, which reach sexual maturity at around 20 months. The Bengal slow loris can live up to 20 years.
The species is listed as endangered on the IUCN Red List, and is threatened with extinction due to growing demand in the exotic pet trade and traditional medicine. It is one of the most common animals sold in local animal markets. In traditional medicine, it is primarily used by wealthy to middle-class, urban women following childbirth, but also to treat stomach problems, broken bones, and sexually transmitted diseases. It is also hunted for food and suffers from habitat loss. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Khao Yai National Park | 🇹🇭 Thailand | |
| 2 | Kaeng Krachan National Park | 🇹🇭 Thailand |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Aquarium featuring native freshwater species from the Mekong River | 🇨🇳 China | |
| 2 | Wild Elephant Valley | 🇨🇳 China |
Possible
About 20% of wildlife watchers report a Bengal Slow Loris sighting in Khao Yai National Park on a given day, based on 21 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 19th most-seen of the 24 mammals we can rate there. Over three days the chance rises to about 40%, and over a week to about 70%, if each day is a fresh chance.
February
In that month about 30% of wildlife watchers report a Bengal Slow Loris in Khao Yai National Park on a given day, against under 5% in March and October, the lowest months. That is one of Khao Yai National Park's driest months, with about 55 mm of rain against 330 mm in September.
Between 2 and 5 pm
Across all the parks we cover, that three-hour window holds the most Bengal Slow Loris sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Yes
Of the 2 parks where we can rate Bengal Slow Loris sightings, Khao Yai National Park has the highest daily chance: about 20%. Next come Kaeng Krachan National Park (Thailand, about 10%).
Same order: Primates
The closest relatives of the Bengal Slow Loris that you can see in Khao Yai National Park (order Primates) are Northern Pig-tailed Macaque (about 80%), Lar Gibbon (about 70%) and Pileated Gibbon (about 30%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Bengal Slow Loris is recorded against all the mammals logged in Khao Yai National Park (21 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.
