Bangka Slow Loris Rediscovered After Nearly a Century Out of Sight
More than 90 Bangka slow lorises, a venomous primate species not scientifically documented since the 1930s, have been recorded on the Indonesian island of Bangka, according to a recent study published in the journal Spixiana and reported by Reuters.
The nocturnal primates were documented between 2015 and 2025 by the Alobi Wildlife Rescue Center, as noted by Reuters and corroborated by UA.News. Researchers found the animals in various parts of the island, including residential gardens, houses, plantations, and roadsides. Timon Glaw, a graduate student in nature conservation and biodiversity management at the Haus des Meeres Aqua Terra Zoo in Vienna and a co-author of the study, stated that the findings demonstrate the species has managed to persist across multiple areas despite decades of scientific neglect and severe habitat loss.
Habitat Loss From Tin Mining and Oil Palm Plantations Threatens Survival
The survival of the Bangka slow loris, scientifically known as Nycticebus bancanus, faces continuous pressure from human activity on the island located off the southeastern coast of Sumatra. Glaw explained to Reuters that the animal’s natural forest habitat has shrunk significantly due to tin mining and land clearing for oil palm plantations.
During the rescue efforts, several animals suffered severe injuries, notably from electrical wires, and a small number died despite receiving treatment. UA.News reported that out of the more than 90 individuals documented by the Alobi Wildlife Rescue Center, 86 recovered successfully and were returned to suitable natural habitats across the island.
Specialized Glands and Delivery Systems Make Primates Uniquely Venomous
Like other slow loris species, the Bangka slow loris is venomous, possessing a rare biological defense mechanism. The animal produces a toxic secretion from specialized glands located near its elbows. When threatened, it raises its arms, mixes the secretion with saliva by licking the glands, and delivers the venom through a bite.
Glaw told Reuters that the venom can trigger severe and potentially life-threatening allergic reactions in humans. Research on related species indicates the venom functions primarily during territorial conflicts with other lorises, while also serving as defense against predators and parasites. The primate uses a specialized toothcomb formed by forward-projecting lower teeth for grooming, gouging tree bark, and delivering venom during bites, along with a secondary tongue beneath its main tongue to clean the toothcomb.
Evolutionary Lineage Links Slow Lorises to Lemurs and Galagos
Taxonomically, the Bangka slow loris shares closer evolutionary ties with the lemurs of Madagascar and the galagos of Africa than with monkeys, apes, or humans. Characterized by reddish-brown fur, large eyes, and distinctive facial markings, the animal moves slowly and deliberately through tree branches, contrasting with the rapid locomotion of typical monkeys, apes and lemurs.
The International Union for Conservation of Nature (IUCN) classified the species as critically endangered and possibly extinct in 2020. The organization Re:wild also included the animal on its list of lost primates. Prior to the recent study, the last formal scientific records from the island dated back to the early 1930s, specifically between 1930 and 1932, leaving decades of uncertainty regarding whether any populations persisted.
Frequently Asked Questions About the Bangka Slow Loris
When was the Bangka slow loris last documented before its recent rediscovery?
The last historical scientific records of the species on Bangka Island dated back to the early 1930s, specifically between 1930 and 1932. For decades afterward, scientists had no reliable data confirming whether the primate still survived on the island.
How many Bangka slow lorises were found, and what happened to them?
The Alobi Wildlife Rescue Center documented more than 90 individuals between 2015 and 2025 across various localities on the island. Following rescue and rehabilitation for injuries sustained from hazards like electrical wires and roads, 86 of the animals were released back into suitable natural habitats.
What organizations and researchers published the new findings?
The findings were published in the journal Spixiana by researchers including Timon Glaw, a graduate student in nature conservation and biodiversity management at the Haus des Meeres Aqua Terra Zoo in Vienna, Austria. The on-the-ground rescue work was carried out by the Indonesian conservation organization Alobi Wildlife Rescue Center.
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