A study unravels the genetic mystery of a cobra divided by sea

COLOMBO – Sri Lanka’s spectacled cobra (Naja naja) carries a two-million-year-old genetic mystery, and a new study finds that the island’s cobras form a genetically distinct lineage, reopening a taxonomic question raised by a Sri Lankan zoologist nearly nine decades ago. The study also established that the spectacled cobra has evolved from an African ancestor that reached the region via the Middle East. The story dates back to 1939, when Sri Lankan zoologist P. E. P. Deraniyagala described a distinctive form of the spectacled cobra with additional eye-like markings on its hood. He named it Naia naia colour var. polyocellata. At the time, it was treated as a color morph of the Indian spectacled cobra than a distinct subspecies native to Sri Lanka. Deraniyagala returned to cobra taxonomy in 1945, proposing several geographical races of the spectacled cobra across the Indian subcontinent, and in 1960, revisited cobra taxonomy. Subsequent morphological work, however, consolidated these geographical forms under Naja naja. Then, in 2022, the question was reopened. A genetic study proposed resurrecting Deraniyagala’s polyocellata as a separate species as Naja polyocellata, after finding substantial genetic differences between Sri Lankan cobras and the Indian mainland cobras. An albino cobra is a snake with a genetic mutation that causes a complete lack of dark pigments, and such unusually colored cobras are reported more often in some regions than others. Image courtesy of Dushantha Kandambi. However, that proposal was challenged the following year. In 2023, herpetologists Wolfgang Wüster of Bangor University, U.K., and Frank…This article was originally published on Mongabay