Tokudaia muenninki

529.

Okinawa Island Spiny Rat

Tokudaia muenninki

French: Mulot d'Okinawa / German: Okinawa-Inselstachelratte / Spanish: Rata espinosa de Okinawa

Other common names: Muennink’s Spiny Rat, Okinawa Spiny Rat

Taxonomy. Tokudamys [sic] osimensis muen- minki D. H. Johnson, 1946,

“Hentona, western coast of northern Okinawa Island, Riu Kiu Islands,” Japan.

Tokudaia muenninki was initially described as a subspeciesof 1. osimensis, but in 2001 Y. Kaneko reviewed its morphological, morphometric, and cytogenetic characters and concluded that it warranted species status. This was confirmed in 2006 by H. Endo and K. Tsuchiya. Monotypic.

Distribution. Okinawa I (Ryukyu Is), S Japan.

Descriptive notes. Head-body 112-175 mm, tail 92-132 mm, ear 22-23 mm, hindfoot 29-8-35 mm; weight 132-169 g. Dorsal pelage of the Okinawa Island Spiny Ratis yellow to reddish brown and ventral pelage grayish to pale yellow. Dorsal spines aredark, and brown to black attip. Tail is short (60-100% of head-body length). Females have two pairs of mammae. Chromosomal complement has 2n = 44, FN = 50.

Habitat. Forest with dense and tall trees and dense undergrowth, above 300 m in elevation. Recent records are from forest dominated by Castanopsis sieboldii (Fagaceae), Lithocarpus edulis (Fagaceae), Distylium racemosum (Hamamelidaceae), and Schima wallichii (Theaceae).

Food and Feeding. Diet consists of seeds of Castanopsis and Lithocarpus, and also mollusks and river crabs.

Breeding. Breeding occurs during October-December. Littersize is 4-10.

Activity patterns. Okinawa Island Spiny Rats are nocturnal. Nests are made on the slope offorest floors, with entrances dug horizontally.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Critically Endangered on The IUCN Red List owing to its very small range combined with intense deforestation, strong decrease of populations resulting from domestic dogs, cats, introduced mongoose predation, and Roof Rat (Rattus rattus) competition. It was rediscovered alive in 2008, 30 years after the previous capture, as reported by F. Yamada and colleagues in 2010.

Bibliography. Abe et al. (2005), Endo & Tsuchiya (2006), Kaneko (2001), Ohdachi etal. (2015), Yamada etal. (2010).