A new species of Pteralopex Thomas, 1888 (Chiroptera : Pteropodidae) from the Fiji Islands J. E. Hill Department of Zoology, British Museum (Natural History), Cromwell Road, London SW7 5BD W. N. Beckon Peace Corps, Suva, Fiji Contents Synopsis ............. 65 Introduction ............ 65 Systematic descriptions ........... 66 Genus Pteralopex Thomas, 1888 66 Pteralopex acrodonta sp. nov. ......... 68 Relationships ............ 75 Dental homologies and dental evolution ........ 76 Acknowledgements ........... 81 References ............. 81 Synopsis The unusual megachiropteran genus Pteralopex is briefly reviewed and considered to include three species, two named many years ago from the Solomon Islands, and a third, here described as new, from the Fiji Islands, whence the genus is recorded for the first time. Cuspidation of the molariform teeth in Pteralopex is considered in detail, with especial reference to the new species, and compared with the similarly cuspi-date condition of the molariform teeth of Harpy ionycter is. Presumed homologies with the cusps of the dilambdodont teeth of the Microchiroptera are examined, with a discussion of the relevance of molariform cuspidation in the Megachiroptera to theories of their dental evolution. Introduction The known megachiropteran fauna of the Fiji Islands has been limited hitherto to two species of the widespread genus Pteropus, one the Pacific fruit bat P. samoensis, the other the Polynesian fruit bat P. tonganus, and to the long-tailed fruit bat Notopteris macdonaldi. None is endemic: P. samoensis is represented on the Fiji Islands by an endemic subspecies, P. s. nawaiensis, the other, nominate subspecies occurring in the Samoa Islands (Wodzicki & Felten, 1975), while P. tonganus is more widely distributed, its subspecies occurring variously from Dampier (Karkar) Island, off the northeastern coast of New Guinea and from Rennell Island, in the Solomon Islands, eastward to the Tonga and Samoa Islands and to Niue Island. This species may occur or have occurred even further to the east, in the Cook Islands, whence bats, apparently pteropodids, have been reported (Smith, 1902, Krzanowski, 1977 : 271) from Raratonga Island (21 14' S, 159 46' W) and where there is evidence of bats (Gill, 1876, Krzanowski, 1977 : 271) on Mangaia Island (21 55' S, 157 55' W). The subspecies of P. tonganus on the Fiji Islands, P. t. tonganus, occurs also in the Tonga and Samoa groups to the east, but to the west is replaced by P. t. geddiei on the Loyalty Islands, New Caledonia and the New Hebrides. The representatives of Pteropus on the Fiji Islands thus display a closer affinity to those of the more easterly islands than to their congeners on the islands to the west of the Fiji group. Notopteris macdonaldi has a rather different distributional pattern : one subspecies, N. m. macdonaldi, occurs on the Fiji Islands and in the New Hebrides (specimens reported from Ponape, Caroline Islands by Jentink (1887 : 268, 1888 : 158) are referred to this subspecies by Andersen (1912 : 798) who also (p. Ixxiv) queries Bull. Br. Mus. nat. Hist. (Zool.) 34 (2) : 65-82 Issued 30 November 1978 65
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