For Indonesia’s newest tarsier, a debut a quarter century in the making
In 1993, scientists Alexandra Nietsch and Carsten Niemitz reported finding tarsiers, a type of small primate, on an island chain off eastern Indonesia’s larger Sulawesi Island.
Sulawesi’s biodiversity was little known then, and the notion that the tarsier from the Togean Islands might be a new species spurred a series of studies that looked at everything from the tarsier’s vocalizations to its DNA sequence.
Finally, in a study published this year in the annual journal Primate Conservation, that initial discovery by Nietsch and Niemitz a quarter of a century ago has been officially confirmed as a new species: Niemitz’s tarsier (Tarsius niemitzi), named in honor of the man “universally regarded as the father of tarsier field biology,” the study says.
“The biodiversity of Sulawesi is much like the biodiversity of the Galapagos Islands, made famous by Darwin’s work,” Myron Shekelle, a professor of anthropology at Western Washington University in Bellingham, WA, and the lead author of the paper describing the new species, told Mongabay in an email.
“Numerous related species were each individually adapted to the specifics of a given island,” he added. “Why would any of us choose to walk away, while species remain undescribed and questions remain unanswered?”
Shekelle was also the lead author of a 2017 report describing two new tarsier species from the northern peninsula of Sulawesi.
While newly described to science, T. niemitzi has long been known to locals by the names bunsing, tangkasi and podi. Its weight and tail length fall within the range of a number of other tarsier species, but the tarsier from the Togean Islands lacks a reduced tail tuft, which is atypical for tarsiers endemic to small islands, according to the study.
Vocalization analysis based on recordings show that its duet is structurally simple, possibly the simplest of all known tarsier duets, the paper adds.
“Togean tarsiers are unique among known tarsier acoustic forms in that they respond in playback experiments to all other tarsier duet calls by duetting themselves,” the authors write.
They also looked into the conservation status of the Niemitz’s tarsier and suggested it be classified as endangered, largely due to its isolation on the Togean Islands, cut off from the Sulawesi main island by water that goes down to depths greater than 120 meters (400 feet).
“The broader implication is that the Togean Islands possess a largely endemic biota of taxa that do not disperse easily across water barriers,” the paper says.
