Muntiacus truongsonensis (Annamite Muntjac) is indigenous to the highland ranges of Indochina. It is named after the Annamite Mountain Range in Vietnam where it was discovered. Its presence has been confirmed in the Hoang Lien Son Range in the Lao Cai province of Vietnam and Southern Laos. Its range limits are unknown but are thought to closely resemble those of Muntiacus rooseveltorum, with the exception that M. truongsonensis extends into higher elevations. (Duckworth and Pine, 2003; Giao, et al., 1998; Sterling and Hurley, 2006; Wilson and Reeder, 2005)
Muntiacus truongsonensis is a mountain dwelling cervid, found in dense, tropical, secondary, evergreen forests. Elevations where M. truongsonensis can be found extend up to and possibly exceed 1,000 m. (Giao, et al., 1998; Timmins, et al., 2008a)
Muntiacus truongsonensis is one of the smaller members of Muntiacus. The exact size of M. truongsonensis is unknown, but it has been described to be approximately 15 kg by local hunters. It has black fur on its legs and bright orange fur on its head. Dorsal pelage is brown and it has a broad flat tail with black dorsal fur and long white ventral fur which distinguishes it from its similar sized relative, Muntiacus rooseveltorum. It has white rings surrounding each hoof. Similar to other muntjac species, M. truongsonensis has ridges running from the top of the snout to the apex of the head, which give rise to short, simple, burred antlers that are hidden by tufts of long fur at the top of the head. Like those of many species of Muntiacus, the canines of M. truongsonensis are long and tusk-like. Muntiacus truongsonensis is the only muntjac species in which females and males have similarly sized canines. No description has been given of juvenile M. truongsonensis. However, many related cervids, including species in Muntiacus, have young with spotted coats. (Giao, et al., 1998; Macdonald, 2001; Sterling and Hurley, 2006; Vrba, 2000)
The mating system of Muntiacus truongsonensis is unknown. Other species in the genus, including Muntiacus vaginalis and Muntiacus reevesi, mate year round. Male M. reevesi defend territories that overlap with those of females. Males compete for mates by locking antlers and pushing against each other. They use their tusks to scratch the faces and necks of rival males. Both sexes of M. reevesi are semi-vocal. Males "buzz" when approaching a female in estrus, and receptive females whine and lower their heads to males. (Deuling and Myers, 2004; Timmins, et al., 2008b; Yahner, 1979)
Members of Muntiacus living in similar habitats as Muntiacus truongsonensis, such as M. reevesi and M. vaginalis, are polygynous and aseasonal breeders. Gestation is variable in Muntiacus. For example, gestation in Muntiacus muntjak lasts for 180 days, while that of M. reevesi lasts for 210 days. (Barrette, 1977; Deuling and Myers, 2004; Macdonald, 2001; Timmins, et al., 2008b; Yahner, 1979)
There is no information available regarding parental investment in Muntiacus truongsonensis, but it is probably similar to that of close relatives. Muntiacus reevesi exhibits minimal parental care and weans offspring at 17 weeks. Like many small cervids in enclosed environments (e.g., forests), M. truongsonensis likely has young that exhibit hiding behavior in which young lie and hide for extended periods of time, while mothers wander off to graze and then return periodically to nurse. (Deuling and Myers, 2004; Fisher, et al., 2002)
No information was found on the longevity of M. truongsonensis in the wild or captivity.
Muntiacus truongsonensis is solitary and is social only during breeding season. No other information is available concerning the general behavior of M. truongsonensis (Giao, et al., 1998; McCullough, et al., 2000; Vrba, 2000)
The home range of Muntiacus truongsonensis is unknown. The average home range of Muntiacus reevesi is about 108 ha, and have a core area that they use most heavily and actively defend. Overall, range size appears to be independent of topography or resource availability. (McCullough, et al., 2000)
Many species of Muntiacus are somewhat vocal, but it is not known if M. truongsonensis is included among them. Males "buzz" when approaching a female in estrus, and receptive females whine and lower their heads to males. Vocal species use barking as an alarm system to warn of potential dangers such as predators. (Yahner, 1980)
Little is known about the diet of Muntiacus truongsonensis. While most munjacs are herbivorous, M. reevesi is known to be omnivorous, eating carrion and small animals. Other species of Muntiacus, such as Muntiacus vaginalis, are generalist herbivores eating a wide range of flora including fruit, twigs, seeds and foliage. (Deuling and Myers, 2004; Macdonald, 2001; Timmins, et al., 2008b)
A range of large predators including tigers, leopards, and crocodiles commonly prey upon many muntjacs. Humans are the only confirmed predator of M. truongsonensis. Potential predatory defense mechanisms of M. truongsonensis are unknown. (Deuling and Myers, 2004; Giao, et al., 1998; Yahner, 1980)
Little is known about the ecosystem roles of Muntiacus truongsonensis. However, close relatives have been described as important seed predators and dispersers and their barking has been suggested to act as a warning system to small mammals. (Chen, et al., 2001; Deuling and Myers, 2004; Timmins, et al., 2008a; Yahner, 1980)
There are no known adverse effects of Muntiacus truongsonensis on humans.
Little is known of the potential conservation needs of Muntiacus truongsonensis, due in part to the difficulty of distinguishing it from closely related muntjacs species. As a result, this species is classified as "data defficient" on the IUCN's Red List of Threatened Species. Possible threats include hunting and habitat loss. (Timmins, et al., 2008a; Trimmins and Cuong, 2001)
Muntiacus truonsonensis was thought to be the rediscovered Muntiacus rooseveltorum as they share similar appearance. However, genetic tests have revealed that M. truongsonensis is indeed a unique species. It is one of a number of artiodactyls discovered at the end of the 20th century in the Oriental region. The late discovery is due to a lack of research in the Truong Son Range. This area borders Laos, Vietnam and Cambodia and has a history of warfare and instability. (Mackinnon, 2000; Vrba, 2000)
Emilia Breitenbach (author), University of Michigan-Ann Arbor, Phil Myers (editor), University of Michigan-Ann Arbor, John Berini (editor), Special Projects.
uses sound to communicate
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
uses smells or other chemicals to communicate
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
A substance that provides both nutrients and energy to a living thing.
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
having the capacity to move from one place to another.
the area in which the animal is naturally found, the region in which it is endemic.
found in the oriental region of the world. In other words, India and southeast Asia.
chemicals released into air or water that are detected by and responded to by other animals of the same species
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them
reproduction that includes combining the genetic contribution of two individuals, a male and a female
uses touch to communicate
Living on the ground.
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
uses sight to communicate
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
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