It belongs to the genus Rhynchocalamus, which comprises three species distributed in southwest Asia - R arabicus, R melanocephalus and R satunini. “Nothing is known about its distribution, population status, natural history or threats,” stated Dr Salvador Carranza, the lead Spanish researcher studying reptiles of Oman.
“The locality of R arabicus is isolated by more than 2,000km from the remainder of the genus, and the single specimen representing this species makes it one of the rarest snakes in the world.” During an expedition in Oman in 2013, a team of scientists working under the ‘Field study for the conservation of the reptiles of Oman’, found a black snake resting between stones in Dhofar’s Wadi Ayoun. It was identified as R.arabicus on the basis of the morphological characters when compared with photographs of the old specimen and its detailed description in the literature. It was later verified by genetic sequencing.
“In this work we present the second-ever reported specimen of R arabicus, which represents the first record of this species and genus for the Sultanate of Oman. This finding constitutes more than a 1,000km range extension of the genus Rhynchocalamus in southern Arabia,” wrote Carranza in his research published in scientific journal Zootaxa.
“The addition of a new genus of snake to the reptile fauna of Oman is surprising, considering the century-long herpetological surveys conducted in the region. The recent observations of rare nocturnal snakes in the southern Arabian peninsula strengthens the importance of conducting new surveys even in relatively well studied places as Dhofar, as well as in less explored regions. “Additional fieldwork in the Dhofar region will be needed to collect more data on the distribution, population status, and natural history of R arabicus,” he said.
Little is known about Rhynchocalamus. And the least known of the species is R arabicus. “Our knowledge on the distribution of all three species is still scarce, being probably the result of their secretive fossorial lifestyle and mostly nocturnal activity,” added Carranza, who works at Institute of Evolutionary Biology in Barcelona, Spain.
The range of R melanocephalus, the best known of all three species, spans from Sinai, Egypt through the Levant to southern Anatolia. R satunini is found from southern Anatolia to Iran and R arabicus was only known from a single specimen collected in Aden, South Yemen in 1932 and described in 1933.
“The distribution of the south Arabian R arabicus is even more enigmatic. The only two known localities are separated by a distance of more than a 1,000km. We assume that this can be attributed to the poor knowledge of the reptile fauna of central and eastern Yemen and that the distribution is, in fact, more continuous.”