Description of a new species of Hoolock gibbon (Primates: Hylobatidae) based on integrative taxonomy

Abstract

We describe a species of Hoolock gibbon (Primates: Hylobatidae) that is new to science from eastern Myanmar and southwestern China. The genus of hoolock gibbons comprises two previously described living species, the western (Hoolock hoolock) and eastern hoolock (H. leuconedys) gibbons, geographically isolated by the Chindwin River. We assessed the morphological and genetic characteristics of wild animals and museum specimens, and conducted multi-disciplinary analyses using mitochondrial genomic sequences, external morphology, and craniodental characters to evaluate the taxonomic status of the hoolock population in China. The results suggest that hoolocks distributed to the east of the Irrawaddy-Nmai Hka Rivers, which were previously assigned to H. leuconedys, are morphologically and genetically distinct from those to the west of the river, and should be recognized as a new species, the Gaoligong hoolock gibbon or skywalker hoolock gibbon (H. tianxing sp. nov.). We consider that the new species should be categorized as Endangered under IUCN criteria. The discovery of the new species focuses attention on the need for improved conservation of small apes, many of which are in danger of extinction in southern China and Southeast Asia.

Cryptic phylogeographic history sheds light on the generation of species diversity in sky‐island mountains

“…The cryptic diversity we observed in S. fusicaudus has also been demonstrated in other mammals we examined (e.g., Koju et al, ; Zhang et al, ), indicating the existence of taxonomically undescribed species (Fan et al, ), and could be the result of highly stable environments in the mountain ranges inhabited by these moles. Such stability could have buffered dramatic global cooling periods since the late Miocene as well as periodical climatic changes during the Pliocene and Pleistocene.…”

“…Nevertheless, except for a handful flagship species such as the giant panda, which have attracted popular attention and scientific interest (Wei et al, ), most of the unique organisms have been overlooked. Recent studies have shown that species diversity in this area is highly underestimated (He et al, ), and the area has become a significant hotspot for the discovery of new species (e.g., Cheng et al, ; Fan et al, ). The pattern of species diversity and the mechanisms behind the origin of the diversity are not well understood.…”

Look in the trees: Hylobatids as evolutionary models for extinct hominins

“…Multiple aspects of the family Hylobatidae make them important comparators for extinct hominins including their taxonomic diversity, and the timing of their divergence (Table ). The family Hylobatidae is composed of four genera and up to 20 species, or 14 by conservative estimates . This taxonomic diversity greatly exceeds extant hominids, and is within the range of the number of proposed extinct hominin genera (4–7), and species (8–20) .…”

“…The family Hylobatidae is composed of four genera and up to 20 species, or 14 by conservative estimates. [21][22][23] This taxonomic diversity greatly exceeds extant hominids, and is within the range of the number of proposed extinct hominin genera (4-7), and species (8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20). 24 Extant members of the family Hominidae include four genera (Homo, Pan, Gorilla, and Pongo), and up to eight different species.…”

The species dilemma and its potential impact on enforcing wildlife trade laws

“…1 Since its publication in 2016, more species have been described. [2][3][4][5][6][7] The latter group even includes a newly recognized species of great ape, Pongo tapanuliensis. 2 New species descriptions often reignite a debate that has long plagued biological sciences: "What is a species?"…”