Researchers have revalidated and concluded that the Himalayan pangolin (Manis aurita) is a distinct extant species, separate from the Chinese pangolin (Manis pentadactyla).
A team of international researchers published the findings in the journal Communications Biology. They drew the conclusion based on extensive genomic and morphological evidence.
The scientists stated that the findings provide a vital baseline for the conservation of one of the world’s most endangered and heavily trafficked animals.
For decades, the Himalayan pangolin was classified as a subspecies of the Chinese pangolin. The study noted, “Historically, three subspecies of M. pentadactyla were recognised: the nominate subspecies M. p. pentadactyla Linnaeus, 1758, described based on specimens from Taiwan; M. p. pusilla Allen, 1906, from Hainan Island; and M. p. aurita Hodgson, 1836, from central Nepal. While the former two have been subject to extensive genetic studies, and their evolutionary relationships as well as distribution across China and SE Asia have been confirmed, the taxonomic status of M. p. aurita has remained comparatively poorly understood.”
But now, by sequencing of the original specimen (the 1836 lectotype) and comparing it with modern data, scientists found that climate change played a key role in diverging the two lineages approximately 1.8 million years ago during the early Pleistocene Epoch.
The ancestors of M. aurita and M. pentadactyla diverged in the early Pleistocene, a period of significant global climatic oscillations. Given that pangolins are generally a warm-adapted species with no historical fossil evidence suggesting their presence in northern China, climatic shifts likely played a crucial role in driving the allopatric separation of the ancestor into western (Himalaya) vs. eastern (East/ Southeast Asia) refugium, the study said.
M. aurita underwent a sharp demographic collapse triggered by the intense cooling and aridification of this period. Unlike the Chinese pangolin, which found stable climatic buffering in the maritime-influenced forests of southern China, the Himalayan region offered a restricted range and severe habitat instability, making M. aurita uniquely susceptible to long-term decline.
The paper added, “Pangolins are highly olfactory reliant mammals, exhibiting significantly enlarged olfactory bulb and turbinals, using smell to forage for ants and termites. As M. aurita and M. pentadactyla adapted to their respective environments, certain genes likely diverged under selection.”
This allopatric separation, maintained by steep climatic and vegetational gradients, eventually led to the emergence of M. aurita as a distinct species.
Additionally, the species experienced a demographic contraction around the 14th century, coinciding with the onset of the Little Ice Age in the Himalayan region. Genomic evidence suggests that even these relatively short-term climatic oscillations left a lasting footprint on the species’ genetic diversity.
Besides genetic heterogeneity, the species is physically distinct from its Chinese relative as the authors of the research noted that M. aurita is significantly larger in body size and skull. It is larger on average (95.2 cm in size) compared to 71.2 cm for the Chinese pangolin. It paradoxically has markedly smaller ears. It also has a shorter and broader nasal bone.
The species’ distribution is restricted to the southern Himalayan foothills, with confirmed populations in Nepal, South Tibet, and Northeast India, including the state of Assam.
Scientists believe that major landscape features, such as the Brahmaputra drainage and the Arakan Mountains, acted as “synergistic filters” that enforced millions of years of evolutionary isolation.
The species is already facing a threat from illegal wildlife trade. “Alarmingly, our findings also reveal that products from this species have infiltrated regulated traditional medicine markets, demonstrating that illegally sourced materials are being laundered through formal supply chains,” the authors said.
They have called for the same level of protection to be given to the species under the CITES Appendix I, given its vulnerability to international commercial trade. The study warns that M. aurita is a prime target for illegal wildlife traffickers.
“The recognition of M. aurita as a distinct species has immediate implications for international regulation and enforcement. All eight currently recognised pangolin species were transferred to CITES Appendix I, thereby prohibiting international commercial trade in those named taxa and their parts under the Convention. We encourage timely coordination between taxonomic updates and regulatory instruments. Specifically, rapid incorporation of revalidated taxa into the standard nomenclatural references used by CITES, and inclusion of M. aurita under Appendix I,” they said.
Beyond poaching, the species faces an internal threat of inbreeding. The researchers found that while the species generally has lower inbreeding levels than the Chinese pangolin, specific populations—particularly those around the Kathmandu Valley—show “exceptionally high” inbreeding levels, indicating they may be suffering from pronounced inbreeding depression.