The phylogenetic placement of the family Tupaiidae has long been controversial. In the past, tree shrews have been varyingly placed in the Order Insectivora or in the Order Primates. Most modern classifications place the tree shrews in their own order, the Scandentia, part of the larger Archontan clade along with Primates, Chiroptera, and Dermoptera. Ptilocercus is the sole member of the subfamily Ptilocercinae.
Perception Channels: tactile ; chemical
The Pentail Tree Shrew is currently on Appendix II of CITES.
A 1995 publication by the IUCN called Eurasian Insectivores and Tree Shrews outlines current plans for Southeast Asian conservation involving Tree Shrews. A partially digital version is available at: http://members.vienna.at/shrew/itsesAP95-cover.html. The section involving Tree Shrews has not yet been digitized.
However the basic problem facing the tree shrew is slash-and-burn clearing of tropical forests for cultivation and human use. As with most threatened species, habitat fragmentation and destruction pose a strong threat to this animal.
CITES: appendix ii
IUCN Red List of Threatened Species: least concern
Ptilocercus lowii is of no economic importance to humans.
Ptilocercus lowii is of no economic importance to humans.
Like most Tupaiids, Ptilocercus lowii is an omnivore. They have been observed eating bananas, grapes, crickets, and grasshoppers (Gould 1978). One study of stomach contents found black ants, cockroaches, beetles, earwigs, cicadas, leaf insects, and even a young forest gecko (/Gymnodactylus mamaorat/) (Lim 1967). This wide variety in diet suggests that the Pentail Tree Shrew is rather adept at capturing food (Gould 1978).
The Pentailed tree shrew is found in peninsular Thailand, Malaysia, Sumatra, northern Borneo and nearby small islands (Corbet 1991; Payne 1985).
Biogeographic Regions: oriental (Native )
This species has been found in primary and secondary forests, rubber farms, and in houses near forest edges. They are often associated with the palm tree Eugeissona tristis. Pentail Tree Shrews are usually caught 1.5-2 meters off the ground on vines and branches. Specimens have been collected at altitudes from sea level to 2000 meters (Muul and Lim 1971). Nests have been reported in large branches and tree trunks 12-20 meters above the ground (Lim 1967).
Terrestrial Biomes: rainforest
Average lifespan
Status: captivity: 2.7 years.
Ptilocercus lowii has a typical body length of 130-140 mm, and a tail length of 160-190 mm. The animal's back is gray to light brown, with a white/yellowish belly (Gould 1978). It is easily identified by the plume like hairs on the latter 2/5ths of the tail. The "pen tail" is proximally black, fading to white distally, making the Pentail Tree Shrew easily recognizable. Individuals also frequently have a black eye mask (Clark 1926).
Range mass: 40 to 62 g.
Other Physical Features: endothermic ; bilateral symmetry
Average basal metabolic rate: 0.24 W.
Very little life history work has been done on Ptilocercus lowii, as it is rare and difficult to capture (compared to other tupaiids). However, they have two pairs of nipples, suggesting litter sizes of 1 to 4 offspring. Typical tupaiid gestation periods are 45-55 days resulting in the birth of babies weighing about 10 grams (Parker 1989).
Three genera of tupaiids (/Tupaia, Urogale, Lyonogale/) have very unusual mother-offspring relationships. After birth the female will nurse the young, who take on about 50% of their initial body weight (5 grams) in milk. The stuffed babies are then left alone, the mother returning only every 48 hours to perform the same mass feeding session. This milk is unusually high in fat content (~26%) which allows the young to maintain high body temperatures (37 C) without the aid of their mother's warmth. The milk is also high in protein (10%) and the babies are ready to leave the nest in only 4 weeks. The mother also leaves a scent at the nest that deters the father or other conspecifics from entering. This avoidance behavior is so strong that food items sprayed with the scent are not touched by other individuals (Parker 1989).
Because captive breeding has not been done with Ptilocercus, whether this strange parenting method characterizes the Pentail Tree Shrew is unknown.
Key Reproductive Features: gonochoric/gonochoristic/dioecious (sexes separate); sexual
Average birth mass: 10 g.
Average number of offspring: 2.
The pen-tailed treeshrew (Ptilocercus lowii) is a treeshrew of the family Ptilocercidae native to southern Thailand, the Malay Peninsula, Borneo, and some Indonesian islands.[2]
It is the only living species in the genus Ptilocercus. All other treeshrew species are grouped in the family Tupaiidae.[1]
The pen-tailed treeshrew occurs from southern Thailand and the Malay Peninsula to northern Sumatra, Siberut, Bangka Island and northwestern Borneo. It inhabits foremost primary forest up to an elevation of 1,200 m (3,900 ft), where undergrowth is dense.[2]
Pen-tailed treeshrews studied in Malaysia spent several hours per night consuming naturally fermented nectar of the bertam palm. This nectar contains one of the highest alcohol concentrations of all natural foods. The pen-tailed treeshrews did not show any signs of intoxication, although they frequently consumed large amounts of this nectar, equivalent of 10–12 glasses of wine adjusted to body weight with an alcohol content up to 3.8%. Measurements of a biomarker of alcohol dehydrogenase suggest that they may be metabolizing it by a pathway that is not used as heavily by humans. Their ability to ingest high amounts of alcohol is hypothesized to have been an evolutionary adaptation. How pen-tailed treeshrews benefit from this alcohol ingestion or what consequences of consistent high blood alcohol content might factor into their physiology is unclear.[3]
The Ptilocercidae are a family within the order Scandentia. Numerous morphological and genetic differences support the classification of the Ptilocercidae as a separate family from the rest of the treeshrews which diverged around 60 million years ago.[4][5] Treeshrews are considered very close relatives of primates, with the colugos being closer to primates.[4]
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: CS1 maint: uses authors parameter (link) The pen-tailed treeshrew (Ptilocercus lowii) is a treeshrew of the family Ptilocercidae native to southern Thailand, the Malay Peninsula, Borneo, and some Indonesian islands.
It is the only living species in the genus Ptilocercus. All other treeshrew species are grouped in the family Tupaiidae.