653.

Limestone White-bellied Rat

Niviventer hinpoon

French: Rat du Korat / German: Karst-Weif 3bauchratte / Spanish: Rata de vientre blanco de caliza

Other common names: Limestone Niviventer, Limestone Rat

Taxonomy. Rattus hinpoon J. T. Marshall, 1976,

“outside the entrance to the bat cave, half-way up the face of a wooded limestone cliff, 200 meters altitude,” Kaengkhoi District, Saraburi Province, Thailand.

Phylogenetic position of N. hinpoon within the genusis unclear and needs to be inves-tigated further. Monotypic.

Distribution. C Thailand.

Descriptive notes. Head-body 120- 160 mm, tail 120-160 mm, ear 17-21 mm, hindfoot 25-28 mm; weight 50-70 g. The Limestone White-bellied Rat is medium-sized and distinctive, with soft pelage. Dorsum is dull buffy gray, with spines mixed throughout. Venter is dark buffy gray, mixed with brown patches and individual hairs with gray bases and buff tips. Tail is short for the genus (¢.100% of head-body length), distinctly bicolored (dark above and white below), and covered with hair. Ears are dark brown; vibrissae are long. Feet are long and slender, with five digits,fifth reduced with small claw. Skull is slender like other species of Niviventer and indistinguishable from the Bukit White-bellied Rat ( N. bukit). There are four pairs of mammae: one pectoral, one post-axillary, one abdominal, and one inguinal. Chromosomal complement is 2n = 46, FN = 54 or 56.

655.

Sundaic Arboreal White-bellied Rat

Niviventer cremoriventer

French: Rat a ventre creme / German: Sunda-\Weif3bauchratte / Spanish: Rata de vientre blanco arborea de Sonda Other common names: Dark-tailed Niviventer, Dark-tailed Tree Rat, Sundaic Arboreal Niviventer Taxonomy. Mus cremoriventer G. S. Miller, 1900,

“mountains of Trong, Lower Siam [= Thailand], at about 3000 ft. [= 914 m] altitude.”

Habitat. Limestone karst habitat. Limestone White-bellied Rats have been collected halfway up the face of a forested limestone cliff, outside entrance to a cave, and at base of limestone cliff in scrubby vegetation. They have also been found inside caves.

Niviventer cremoriventer has not been included in any phylogenetic studies and is in need of revision because it might represent a species complex. Subspecies have been recognized, but these need validation. Monotypic.

Food and Feeding. No information.

Breeding. No information.

Activity patterns. The Limestone White-bellied Rat is mostly nocturnal, terrestrial, and cursorial.

Distribution. Extreme S Myanmar (Mergui Archipelago), peninsular Thailand and offshore Is (Butang, Terutau, and Langkawi), Malay Peninsula and offshore Is (Penang and Tioman), Anambas Is (Jimaja), Sumatra and adjacent Nias, Belitung, and Bangka Is, Borneo and some offshore Is (Balambangan, Banggi, Malawali, Lamukutan, and Sebuku), Java, and Bali.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Endangered on The IUCN Red List. The Limestone White-bellied Rat has a very restricted distribution and is found in Khao Yai National Park. Habitat degradation, especially in limestone forests, is a major threat. It can be locally common, but there are few details on its natural history, which are criti-cally needed to enhance its conservation.

Descriptive notes. Head—body 133 mm, tail 181 mm; weight 77 g(averages). The Sundaic Arboreal White-bellied Rat is small, similar to the Langbian Tree Rat ( Chiromyscus langbianis). Pelage is soft, with flexible spines and black guard hairs mixed throughout. Dorsum is fulvous brown, becoming more orangish on sides. Dorsum and white venter are sharply demarcated. Feet have brown stripe that extends to white toes. Tail is c.136% of head-body length on average, covered in dark hairs, and unicolored (dark brown); it has dark hair tuft at tip. Ears are dark brown; vibrissae are long. There are five digits on each foot, with fifth digit reduced with small claw. Skull is elongated and narrow. There are four pairs of mammae: one pectoral, one post-axillary, one abdominal, and one inguinal. Chromosomal complement is 2n = 46, FN = 54 and 60.

Bibliography. Francis (2008), Latinne et al. (2011b), Li Yuchun et al. (2008), Marshall (1976, 1977b), Musser (1981a), Musser & Carleton (2005).

6H4.

Indochinese Mountain White-bellied Rat

Niviventer tenaster

French: Rat du Mulayit / German: Indochinesische Weiftbauchratte / Spanish: Rata de vientre blanco de Indochina

Other common names: Indochinese Mountain Niviventer, Tenasserim White-bellied Rat

Habitat. Primary forest, secondary wooded habitats, and disturbed logged habitat at elevations up to 1650 m (Mt. Kinabalu on Borneo).

Taxonomy. Epimys tenaster Thomas, 1916,

“Mount Muleyit, Tenasserim [Kayin State, southern Burma]. Alt. 5000-6000" [= 1525-1830 m].”

Food and Feeding. The Sundaic Arboreal White-bellied Rat mainly eats fruit and seeds. Breeding. Sundaic Arboreal White-bellied Rats reach sexual maturity and 50 g; litters have 2-5 young.

Niviventer tenaster is morphologically most similar to N. confucianus, but phylogenetic relationships are unresolved, and further genetic and morphological studies are needed to determine its placement within Niviventer . Recently, the Hainan populaLion was split into its own species, N. lotipes,

Activity patterns. The Sundaic Arboreal White-bellied Rat is nocturnal, spending its days in a hanging nest it made. This species is arboreal but has regularly been captured on the ground as well as above it.

Movements, Home range and Social organization. Sundaic Arboreal White-bellied Rats create free-hanging nests made of plant fibers for day use.

Status and Conservation. Classified as Vulnerable on The IUCN Red List. Although the Sundaic Arboreal White-bellied Rat has a large distribution and occurs in many protected areas, its population is estimated to have decreasedby ¢.30% in the last ten years due to habitat destruction and degradation. Nevertheless,it is easily and commonly captured throughout its distribution.

based on karyological data and later validated by phylogenetic data, although morphological studies are needed to further validate this view. Monotypic.

Distribution. WC & S Myanmar, NW Thailand (Chiang Mai Province), Laos, Vietnam, and S Cambodia (Damrei Mts).

Bibliography. Duncan etal. (1974), Li Yuchun et al. (2008), Musser (1973b, 1981a), Musser & Carleton (2005), Nor (2001), Phillipps & Phillipps (2016), Pimsai et al. (2014), Ruedas, Aplin et al. (2008), Wells, Linsenmair et al. (2004), Wells, Pfeiffer et al. (2006), Yong (1969).

Descriptive notes. Head-body 120-190 mm, tail 175-235 mm, ear 23-26 mm, hindfoot 32-35 mm; weight 50-140 g. The Indochinese Mountain White-bellied Ratis larger than all other species of Niviventer except the Confucian White-bellied Rat ( N. confucianus), which it is very similar to, and the Spiny Taiwan White-bellied Rat ( N. coninga), which might be larger. Pelage is soft, covered with dark brown sturdy but flexible spines. Dorsum is dark brown, with lighter but prominent ruby reddish side—lighter than the Indochinese White-bellied Rat ( N. fulvescens) and without chocolate brown hue of the Confucian White-bellied Rat and spinier than the Bukit White-bellied Rat ( N. bukit). Top offeet of the Indochinese Mountain White-bellied Rat have dark brown or chestnut stripe that stops just before white toes. Dorsum and venter are sharply demarcated. Venter is pure white, without any chest or chin markings.Tail is ¢.151% of head-body length and sharply bicolored, dark brown above and paler below, although dark top can fade toward tip in some specimens, although it is never completely unicolored as inthe Himalayan White-bellied Rat ( N. niviventer). There are five digits on each foot, with fifth digit reduced with small claw. Skull is large, exceeding 41 mm, but lightly built and elongated. There are four pairs of mammae: one pectoral, one post-axillary, one abdominal, and one inguinal. Chromosomal complement is 2n = 46, FN = 54.

656.

Montane Sumatran White-bellied Rat

Niviventer fraternus

French: Rat jumeau / German: Sumatra-WeilRbauchratte / Spanish: Rata de vientre blanco de montana de Sumatra

Other common names: Montane Sumatran

Niviventer

Taxonomy. Epimys fraternus H. C. Robinson & Kloss, 1916,

“Sungei Kumbang, Ko-rinchi, 4,700’ [= 1432 m], West Sumatra.”

Niviventer fraternus was included as a sub-species of N. rapit along with N. cameroni, but it is recognized as a distinct species here. It has not been included in any genetic studies, but multivariate analysis of morphological. traits. has. allied. it. with N. fulvescens . Monotypic.

Habitat. Montane rainforests at elevations of 1300-3000 mFood and Feeding. No information.

Distribution. W Sumatra.

Breeding. No information.

Descriptive notes. Head-body 162 mm, tail 231 mm, hindfoot 32-5 mm (taken from original description). No specific data are available for body weight. The Montane Sumatran White-bellied Rat is large, with spiny yet soft pelage. Itis equalin size to or larger than the Montane Bornean White-bellied Rat ( N. rapit) and smaller than the Cameron Highlands White-bellied Rat ( N. cameroni).Dorsum is dark reddish brown and lighter on sides. Venter is white, and dark brown patch can occur on chest or neck. Ears are dark brown;vibrissae are long. Tail is ¢.140% of head-body length and hairy, and it can either be unicolored (dark brown) or bicolored (dark brown above, lighter below). Dark brown stripe goes down hands, stopping before white feet. There are five digits on each foot, with fifth digit reduced with small claw. Skull is elongated and slender like other species of Niwiventer, and zygomatic plate is wider than on the Cameron Highlands White-bellied Rat and the Montane Bornean White-bellied Rat. There are four pairs of mammae: one pectoral, one post-axillary, one abdominal, and one inguinal.

Activity patterns. The Indochinese Mountain White-bellied Rat is nocturnal and mostly terrestrial. It travels across vines and has been captured on woody lianas threading through dense stands of bamboo. It was also caught at primary forest on the ground and 1-2 m aboveground (on trees and lianas) on the Dalat Plateau in southern Vietnam.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Least Concern on The IUCN Red List (including N. lotipes). The Indochinese Mountain White-bellied Ratis not reported as abundant anywhere but is represented by large collections of specimens.

Bibliography. Abramov et al. (2010), Aplin (2016g), Balakirev & Rozhnov (2010), Balakirev et al. (2011), He Kai & Jiang Xuelong (2015), Jing Meidong et al. (2007), Li Yuchun et al. (2008), Lu Liang et al. (2015), Lunde et al. (2003), Musser (1973b, 1981a), Musser & Carleton (2005), Smith & Yan Xie (2008).

Habitat. Montane forests at elevations of 1250-3500 m.

Food and Feeding. No information.

Breeding. No information.

Activity patterns. The Montane Sumatran White-bellied Rat might be more arboreal than terrestrial and is probably nocturnal.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Least Concern on The IUCN Red List. The Montane Sumatran White-bellied Rat might be threatened by habitat loss at lower elevations, but no major threats are known. It occurs in Kerinci Seblat National Park and a few other protected areas.

Bibliography. Aplin (2016b), Chasen (1940), Corbet & Hill (1992), Musser & Carleton (2005), Robinson & Kloss (1916, 1918).