For a long time it was considered that there were two species of
Macaques present in the forests of southeastern Tibet, Macaca assamensis assamensis (the Assam Macaque and Macaca mulatta (the Rhesus Macaque). However in recent years work by Indian researchers in Arunachal
State (referred to in China as ‘Indian-controlled Tibet'), which shares
continuous forests with southeastern Tibet, has led to the description a new
species, Macaca munzala (the Arunchal Macaque) and the
detection of a fourth species Macaca thibetana (the Tibetan Macaque),
previously thought not to be present in the region. However not all
primatologists in India have accepted these results, suggesting that instead
the known species may be more variable than previously thought. In response to
this, scientists on the Chinese side of the border began a series of
observations of Macaques present there in 2013 and 2014, and set camera traps
in the forests Modog County in southeastern Tibet. To their surprise this
resulted in the discovery of what appears to be another species of Macaque in
the region, distinguishable by its coat and genital anatomy.
In a paper published in the American Journal of Primatology on 25 March
2015, Cheng Li of the Imaging Biodiversity Expedition, Chao Zhao of the Institute
of Eastern-Himalaya Biodiversity Research at Dali University and Peng-Fei Fan
of the Faculty of Forestry at Southwest Forestry University formerly describe
this new species as Macaca leucogenys,
the White-cheeked Macaque.
Traditionally new species have been described by the assignation of
type specimens in museums, against which other specimens can be compared to
establish whether or not they belong to the same species. However the
International Code of Zoological Nomenclature allows for the designation of
photographs as types in the case of Primates, due to ethical concerns about
killing wild specimens, and Li et al. take
advantage of this provision to describe the new species from photographic data
only, with the intention of obtaining museum specimens in the future.
Photo showing robust White-cheeked Macaque with brown
to dark brown dorsal pelage and relative short tail. The end of the tail bends
towards the ground in some individuals. White hair on cheeks and ears are
visible. Li et al. (2015).
The White-cheeked Macaque has a relatively uniform brown colouration
on its body, though the belly is lighter than the back. The hair on the muzzle
is the same colour as the body, but the cheeks and ears are white. In older
individuals these white hairs grow longer, and white hairs also appear on the
snout. Juveniles lack white cheeks. The tail is hairless and tapering, being
distinctly thicker at the base then the tip; in many individuals it has a
distinct downwards kink close to it’s tip.
Family group of White-cheeked Macaques. Adult male in
the right, adult female in the left and two small juveniles. Li et al. (2015).
White-cheeked Macaques were found in the forests of Madog County at
altitudes of between 1395 m and 2700 m, an environment that ranges from
tropical forests, through evergreen broadleaf forest and into mixed
broadleaf-conifer forest, suggesting a degree of environmental flexibility. It
may also be present in neighbouring counties of China or other Himalayan
nations.
Map showing the rough distribution range of each
species or subspecies of Macaca in
southeast Tibet. Li et al. (2015).
At the moment all the forests of Modog County are protected by the
Yarlung Zangbo Grand Canyon Nature Reserve, which prohibits destructive
practices such as slash and burn agriculture. However local people in the area
are known to kill Primates caught raiding crops, and also to occasionally
actively hunt Macaques. More seriously the Chinese government is currently
planning a series of hydroelectric dams in Modog County, including one which
would completely flood the area where the White-cheeked Macaque. This threatens
to directly destroy a large area of environment inhabited by the White-cheeked
Macaque and other rare Primates, and in addition will bring a large number of
workers into the area, which will lead to additional environmental disruption,
by the building of roads, houses and other facilities for workers, as well as
being likely to fuel a rise in the bushmeat trade in the area. Li et al. therefore call for more work to
study and protect this important environment to be carried out as a matter of
some urgency.
See also…
A new species of Titi Monkey from the Amazon Rainforests of Brazil. Titi Monkeys, Callicebus spp., are a large group of
New World Monkeys distributed throughout much of the Amazonian and Atlantic
Rainforests of South America. Views on their taxonomy have varied considerably...
Burmese Snub-nosed Monkey found in China.The discovery of the Burmese Snub-nosed Monkey, Rhinopithecus strykeri, was announced in January 2011 in a paper in the American Journal of...
Follow Sciency Thoughts on Facebook.
