Quick answer
IUCN status: VulnerableThomas’s Langur at a glance
Thomas’s Langur (Presbytis thomasi) is a mammal in the family Cercopithecidae. In Indonesia, observation records come mainly from North Sumatra, Aceh. It is endemic to Indonesia, living naturally only in Northern Sumatra (Aceh and northern North Sumatra). Diet: young leaves, fruit and seeds; occasionally insects and snails; a herbivore. IUCN Red List status: Vulnerable. It is a legally protected species in Indonesia (Regulation P.106/2018).
| Scientific name | Presbytis thomasi |
|---|---|
| Indonesian name | Kedih |
| Group | Mammals |
| Family | Cercopithecidae |
| Observation records | North Sumatra, Aceh |
| Linked habitats | Tropical Rainforests, Freshwater Wetlands |
| Taxonomic group | Primates |
| GBIF records | 398 human-observation records, 2016–2026 |
| Data retrieved | 2026-09-23 |
| IUCN status | Vulnerable · IUCN Red List (via GBIF) · checked 1 October 2026 |
| Legal protection in Indonesia | Protected · Regulation P.106/2018 · annex no. 25 |
| Diet type | Herbivore (plant-eater) — young leaves, fruit and seeds; occasionally insects and snails · IUCN Red List |
| Reproduction | Giving birth to live young (viviparous) · Animal Diversity Web |
| Observance days | Indonesian Primate Day (30 January) |
| Active | Diurnal (active by day) · EltonTraits 1.0 (Wilman et al. 2014, Ecology 95:2027), MamFuncDat.txt |
| Endemic to Indonesia | Yes — Northern Sumatra (Aceh and northern North Sumatra) · IUCN Red List |
In this guide (13)
What is the Thomas’s Langur?
Thomas’s Langur refers to Presbytis thomasi, in the genus Presbytis, family Cercopithecidae, and order Primates. The scientific name follows the accepted taxon in the GBIF Backbone Taxonomy. Common names can vary between places; the scientific name distinguishes this species from relatives.
What is known about the Thomas’s Langur?
Thomas's langur is restricted to northern Sumatra; habitat loss is reported as a pressure, while each local group needs separate assessment.
Read that fact alongside the scientific name and species source, not as proof from an unclear photograph. Populations, ages and taxonomic limits can differ; when identification is uncertain, record the broader group.
Evidence: Species account — background reading ↗
Habitat and field observations of the Thomas’s Langur
Thomas's langurs are recorded in lowland, swamp and riverine forests and some gardens near forest. Documented foods include young leaves, fruit, seeds and flowers.
Evidence: GBIF species treatments — natural-history accounts ↗
How many Indonesian records name the Thomas’s Langur?
When checked on 2026-09-23, the GBIF search returned 398 human-observation records from Indonesia under this species name for 2016–2026. That is a count of indexed records, not an estimate of population, abundance or unique individuals. Observation effort can vary by location, and the count may change as records are added or identifications revised.
Evidence: GBIF occurrence search — Indonesia, human observations, 2016–2026 ↗
Where were observations reported?
Place labels appearing in the results include North Sumatra, Aceh. They are labels attached to records, not a complete range map or evidence that the species occurs only there. Some labels may be broad or inconsistent. Check the underlying records before using the location information for field decisions.
Evidence: GBIF occurrence search — Indonesia, human observations, 2016–2026 ↗
How can you observe the Thomas’s Langur?
Watch from a distance, do not feed, and avoid sharing precise locations of vulnerable dens or resting sites. Do not try to catch or touch wild mammals. A well-documented sighting helps others check the identification without turning one encounter into a conservation-status claim.
Explore related animals
To explore this group further, compare Thomas’s Langur with Sumatran Surili, Javan Surili, Southern Pig-tailed Macaque. These links reflect a shared genus, family, order, class or catalogue group; taxonomic proximity does not imply identical habitat needs or conservation status.
Explore related habitats
These habitat relationships are supported by species sources in this guide. This is not a complete range map.
Scientific classification of the Thomas’s Langur
| Kingdom | Animalia |
|---|---|
| Phylum | Chordata |
| Class | Mammalia |
| Order | Primates |
| Family | Cercopithecidae |
| Genus | Presbytis |
| Species | Presbytis thomasi |
Source: GBIF Backbone Taxonomy, adjusted to the ranks commonly used in school biology (for example class Reptilia).
Common questions about Thomas’s Langur
What is the scientific name of Thomas’s Langur?
The scientific name of Thomas’s Langur is Presbytis thomasi, in the family Cercopithecidae and the order Primates. In Indonesian it is called Kedih.
What kind of animal is Thomas’s Langur?
Thomas’s Langur is a mammal in the family Cercopithecidae. By diet it is a herbivore (plant-eater): a young leaves, fruit and seeds; occasionally insects and snails. It is also endemic to Indonesia.
Where does Thomas’s Langur live in Indonesia?
Observation records of Thomas’s Langur summarised in this guide mainly come from North Sumatra, Aceh. That list is not a complete range map.
Thomas’s Langur is endemic to Indonesia and lives naturally only in Northern Sumatra (Aceh and northern North Sumatra). Source: IUCN Red List.
Source-supported habitats: Tropical Rainforests, Freshwater Wetlands.
What does Thomas’s Langur eat?
Thomas’s Langur is a young leaves, fruit and seeds; occasionally insects and snails. That makes it a herbivore (plant-eater). Source: IUCN Red List.
How does Thomas’s Langur reproduce?
Thomas’s Langur reproduces by giving birth to live young (viviparous). Source: Animal Diversity Web.
Is Thomas’s Langur nocturnal?
The cited source records Thomas’s Langur as diurnal (active by day). Source: EltonTraits 1.0 (Wilman et al. 2014, Ecology 95:2027), MamFuncDat.txt.
See also the list of nocturnal and diurnal animals in Indonesia.
What is the scientific classification of Thomas’s Langur?
Scientific classification of Thomas’s Langur: kingdom Animalia, phylum Chordata, class Mammalia, order Primates, family Cercopithecidae, genus Presbytis, species Presbytis thomasi.
Source: GBIF Backbone Taxonomy, adjusted to the ranks commonly used in school biology.
Is Thomas’s Langur endangered?
Yes. On the IUCN Red List, Thomas’s Langur is listed as Vulnerable: it is considered to face a high risk of extinction in the wild. Source: IUCN Red List (via GBIF), checked 1 October 2026.
This global category is separate from national legal protection. Is Thomas’s Langur protected in Indonesia?
Is Thomas’s Langur protected in Indonesia?
Yes. Thomas’s Langur (Presbytis thomasi) is a protected species in Indonesia under Environment and Forestry Ministerial Regulation No. P.106/MENLHK/SETJEN/KUM.1/12/2018 on protected plant and animal species (annex, entry 25).
Article 21(2) of Law No. 5 of 1990, as amended by Law No. 32 of 2024, prohibits anyone from hunting, catching, injuring, killing, storing, owning, keeping, transporting or trading a protected animal, alive or dead, including its body parts, eggs and nests.
If you see this animal being traded, kept or injured, contact the local BKSDA office.
Can Thomas’s Langur be kept as a pet?
No. Because Thomas’s Langur is a protected species, catching, owning, keeping, transporting or trading it without a permit is prohibited by law. Trading without a permit through electronic media is also prohibited.
If you see this animal for sale or being kept, report it to the local BKSDA office.
Sources & references
- GBIF Backbone Taxonomy — accepted taxon ↗
- GBIF occurrence search — Indonesia, human observations, 2016–2026 ↗
- GBIF species treatments — natural-history accounts ↗
- iNaturalist — exact species taxon and community observations ↗
- Species account — background reading ↗
- Peraturan Menteri LHK Nomor P.106/MENLHK/SETJEN/KUM.1/12/2018 tentang Jenis Tumbuhan dan Satwa yang Dilindungi ↗
- IUCN Red List ↗
- Animal Diversity Web ↗
- EltonTraits 1.0 (Wilman et al. 2014, Ecology 95:2027), MamFuncDat.txt ↗
- GBIF Backbone Taxonomy (GBIF) ↗
- IUCN Red List of Threatened Species, version 2026-1, via GBIF (CC BY 4.0) ↗
References can change. Check dates and context in the original source. How we use sources and data →
Cite this page
Credit PanduanHewan when referring to this page. Check the original evidence sources before reusing a claim.
PanduanHewan. Thomas’s Langur (Presbytis thomasi). Last substantive update: 1 October 2026. https://panduanhewan.org/en/species/presbytis-thomasi/