Rattus owiensis Troughton, 1945

Rec. Aust. Mus. 21(6): 374. (25 June 1945).

Common name. Yapen Island Rat.

Current name. Rattus jobiensis Rümmler, 1935; following Taylor et al. (1982) and Musser & Carleton (2005).

Holotype. M.6993 by original designation. Male, subadult, [collector’s No. Owi Is. 30], skull, study skin, presented by Lt. Col. C. B. Philip and Major G. M. Kohls in August 1944, registered September 1944.

Condition. Incomplete and damaged cranium; braincase fragmented, missing left auditory capsule, hole in right auditory bulla (which is detached), missing jugal bone of both zygomatic arches; both dentaries complete. Study skin: bald patch on throat, three bald patches on ventral abdominal area; otherwise in good condition.

Type locality. Owi Island, Schouten Island Group, Cenderawasih (formerly Geelvink) Bay, Papua Province, Indonesia.

Paratypes. (3, 2 by subsequent determination; species composite). Same data as holotype: M.6992 by original designation, female (allotype), subadult, skull, study skin (= R. jobiensis); M.6994, male, skull, study skin (= R. exulans browni); marked by Troughton as paratype in register and given as owiensis; M.6995, male, body in alc., (= Rattus exulans browni), marked in the register as owiensis by Troughton though not marked as a paratype, but marked “ paratype ” by Troughton on the specimen index card.

Comments. The number of specimens in the type series is not indicated by Troughton, who cites registration numbers for the holotype and allotype only. The holotype is a male, although Troughton variously refers to it as male and female in the original account. Taylor et al. (1982) note that the type series is a composite of two species. They assigned the male holotype, and paratype female M.6992, both of which they state are subadult, to R. jobiensis, and the paratypes M.6994 and M.6996 to Rattus exulans browni. However these authors do not mention M.6995, the only spirit specimen, which is also Rattus exulans browni. We have not included M.6996 (which is not indicated as a paratype by Troughton) in the type series because of the uncertain identity expressed by Troughton, who marked it in the register as “ R. browni (owiensis juv?)”.