A hooded, venom-spitting snake that was pickled and has been at a museum in Zimbabwe for 40 years has been identified as a new species based on DNA analysis.
The snake, named the Nyanga rinkhals (Hemachatus nyangensis), comes from the mountainous Nyanga region of Zimbabwe, but it may have already gone extinct.
A female specimen kept at the Natural History Museum of Zimbabwe in Bulawayo was found run over in 1982. It was initially identified as another rinkhals species, Hemachatus haemachatus, that occurs in South Africa, Lesotho and Eswatini. But Nyanga is separated from those southern populations by at least 700 kilometres and it was long suspected that the two could, in fact, be distinct species.
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The poor state of the bottled sample has, until now, prevented a meaningful genetic analysis.
at the University of Bangor, UK, says his collaborators have developed new techniques to extract DNA from very old specimens, like cave bears and mammoths. Major and his colleagues used these same methods to get DNA from the bottled rinkhals.
鈥淚t was those DNA fragments we used in conjunction with DNA from specimens from southern Africa to say that this [the Nyanga rinkhals] is a new species that probably diverged between 7 and 14 million years ago,鈥� says Major.
The last time a Nyanga rinkhals was sighted in the wild was 1988, and the research team now fears the worst. The stunted woodlands and rolling grasslands of the 47,000-hectare Nyanga National Park are threatened by the spread of alien tree species, such as wattle and pine, which the snakes aren鈥檛 adapted to live among.
鈥淚f it isn鈥檛 already extinct, it鈥檚 probably very vulnerable to extinction,鈥� says Major. Conservation measures will need to be put in place if the reptiles are found alive, he says.
Rinkhals, which differ from closely related egg-laying cobras because they give birth to live young, are tricky to find in the wild, says Major. Cellular material, or environmental DNA from things like recently shed snakeskins, could provide vital proof of life, but might be equally hard to find in the vast expanse of the Nyanga mountains.
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