No longer based on photographs alone: refuting the validity of golden-crowned langur Presbytis johnaspinalli Nardelli 2015 (Mammalia, Primates, Cercopithecidae)

• Main Author: Vincent Nijman
• Format: Article
• Language: English
• Published: Pensoft Publishers 2021-02-01
• Series: Zoosystematics and Evolution
• Online Access: https://zse.pensoft.net/article/62235/download/pdf/

Increasingly, new species are being described without there being a name-bearing type specimen. In 2015, a new species of primate was described, the golden-crowned langur Presbytis johnaspinalli Nardelli, 2015 on the basis of five photographs that were posted on the Internet in 2009. After publication, the validity of the species was questioned as it was suggested that the animals were partially and selectively bleached ebony langurs Trachypithecus auratus (É. Geoffroy Saint-Hilaire, 1812). Since the whereabouts of the animals were unknown, it was difficult to see how this matter could be resolved and the current taxonomic status of P. johnaspinalli remains unclear. I present new information about the fate of the individual animals in the photographs and their species identification. In 2009, thirteen of the langurs on which Nardelli based his description were brought to a rescue centre where, after about three months, they regained their normal black colouration confirming the bleaching hypothesis. Eight of the langurs were released in a forest and two were monitored for two months in 2014. The description of their behaviour, photographs and analysis of their cytochrome b genes confirms them as ebony langurs. There is no evidence to support the notion that the golden-crowned langur represents intermediates between melanistic and erythristic ebony langurs, nor that it represents a new species. As such, Presbytis johnaspinalli Nardelli, 2015 is a junior synonym of Trachyptihecus auratus (É. Geoffroy Saint-Hilaire, 1812). This case underscores the importance of assembling a sufficiently varied amount of data prior to describing new species and studying the actual type specimens.