Pteropus Erxleben, 1777

Nishioka, Yuichiro, Nakagawa, Ryohei, Nunami, Shin & Hirasawa, Satoshi, 2016, Small Mammalian Remains from the Late Holocene Deposits on Ishigaki and Yonaguni Islands, Southwestern Japan, Zoological Studies 55 (5), pp. 1-21 : 8

Genus Pteropus Erxleben, 1777

Material examined: A left M 1 (MPM-Fo 2804).

Locality: Sabichi Fissure, Ishigaki Island.

Measurements: M 1 (MPM-Fo 2804): L, 5.64 mm; W, 2.92 mm.

D e scri p ti o n: Th e to o th i s si mp l e l i ke a unicuspid tooth of carnivorans. The occlusal surface shows an ellipse outline, and is composed of the prominent protoconid and the small metaconid. There is a crest along the occlusal outline. The talonid basin is broad and slightly concaved. The tooth is anchored by two robust roots.

Remarks: A lower molar of flying fox, or Pteropus , lacks the original tribosphenic pattern (the W-shaped pattern), which is represented by microchiropteran species. Three species of Pteropus are known in Japan: P. pselaphon on Ogasawara Islands (1000 km south of Honshu), extinct P. loochoensis on Okinawa Island, and P. dasymallus in the Ryukyu Islands ( Kinjo 2009; Kinjo and Izawa 2009; Kinjo and Nakamoto 2009). Fossils of Pteropus dasymallus were reported from Ishigaki Island, although it has not been compared with other species ( Hasegawa and Nohara 1978). Moreover, the Late Pleistocene and Holocene deposits on Miyako and Ishigaki Islands recently yielded Pteropus remains, but these were not identified at a species level due to a deficiency of comparisons with P. loochoensis and P. pselaphon ( Nakagawa et al. 2012; Kawamura and Kawamura 2013). The lower molar from Sabichi Fissure is not different from that of living P. dasymallus , based on the specimens collected from the Ishigaki Island.