647.

Spiny Taiwan White-bellied Rat

Niviventer coninga

French: Rat de Coxinga / German: Stachelige Taiwan-WeiRbauchratte / Spanish: Rata de vientre blanco espinosa de Taiwan

Other common names: Coxing's Niviventer, Coxing’s White-bellied Rat, Formosan Niviventer, Spiny Taiwan Niviventer

Taxonomy. Mus coninga Swinhoe, 1864,

“Formosa [= Taiwan].”

Niviwventer coninga has been included in N. coxingi and N. coxinga, but N. coninga has priority. Phylogenetic position of N. cominga 1s uncertain and needs additional investigation. Monotypic.

Distribution. Taiwan.

Descriptive notes. Head-body 140- 205 mm, tail 174-262 mm, ear 22-29 mm, hindfoot 30-37 mm; weight 108-176 g. The Spiny Taiwan White-bellied Rat is possibly the largest species of Niviventer, with soft pelage and flexible spines and guard hairs throughout. Dorsum is reddish brown to yellowish brown, sharply demarcated from venter, which is creamy white without brown spot on chest or neck. Brown stripe on top offeet stops right before white toes. Tail is c.126%of head-body length, haired, and distinctly bicolored, brown above and paler below. 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. The tick Dermacentor bellulus and the lungworm Angiostrongylus cantonensis have been recorded from the Spiny Taiwan White-bellied Rat. Some individuals from Mount Alishan were infected Emmonsia crescens, which causes Adiaspiromycosus. There are four pairs of mammae: one pectoral, one post-axillary, one abdominal, and oneinguinal. Chromosomal complement is 2n = 46, FN = 54.

Habitat. [Lowland tropical broadleafforests and associated edges and scrubland at elevations up to 2000 m.

Food and Feeding. The Spiny Taiwan White-bellied Rat eats seeds, fruits, forbs, and arthropods. It hoards seeds by scattering or lardering.

Breeding. Breeding occurs year-round, but it occurs more often during middle ofdry season and middle of wet season due to more plentiful food sources, or less often during late dry season, the coldest time ofthe year, to reduce energy usage. Larger males have more reproductive success. Litters have 2-5 young. Sexual maturity is reached at 5-5 months for individuals born in summer and 9 months for those born in winter. A single female can have up to three litters in herlifetime. Longevity is ¢.5 months.

Activity patterns. The Spiny Taiwan White-bellied Rat is primarily terrestrial but occasionally arboreal. It is strictly nocturnal, becoming active from 01:00 h to 13:00 h, and is most active in winter when nights are longer. It probably has a number of 2-3 hour activity cycles during its active period. There is no activity detected during the day, and activity is strictly determined by sunset and sunrise. It nests in shrubs throughout the day.

Movements, Home range and Social organization. Overall population densities are 2-5 ind/ha. Females have more static and well-defined home ranges than males. Home ranges are 200-20,200 m? for males and 600-4800 m* for females. In the Experimental Forest of National Taiwan University at Chitou, central Taiwan, home ranges of males were larger and overlapped with other individuals home ranges more often than females, which had smaller home ranges.

Status and Conservation. Classified as Least Concern on The IUCN Red List. The Spiny Taiwan White-bellied Rat is common throughoutits distribution, which encompasses more than 20,000 km?*. Overall population is probably large and stable, and it occurs in at least Yushan National Park, although it might be fragmented or becoming fragmented due to human encroachment. The Spiny Taiwan White-bellied Rat has been well-studied compared with most other species of Niviventer . It is classified as least concern on China’s Regional Red List.

Bibliography. Adler (1996), Apanaskevich & Apanaskevich (2015), Johnston & Smith (2016e), Li Yuchun et al. (2008), Lu Liang et al. (2015), Musser (1981a), Musser & Carleton (2005), Ooi Hongkean & Lin Sanching (1996), Pei (1995), Smith & Yan Xie (2008), Wang Yuhuang et al. (2008), Wu Haiyin & Yu Hontsen (2004), Yong & Eamsobhana (2013), Yu Hontsen & Lin Yaosung (1999), Yu Hontsen et al. (1996).