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Discussion
However surprising Suyanto and Watts’ (2002) conclusion was that a species known from fossils only was still living, it was certainly not unlikely. Another rat that had been described from fossils by Musser has in fact been recently recognised in the Recent fauna. Musser (1981) had described Floresomys naso on the basis of Holocene dentaries and lower teeth from Liang Toge. As the genus name was preoccupied, he proposed the replacement name Paulamys (Musser et al., 1986). A living specimen of a murid at least closely related to P. naso was collected in 1989 (Kitchener et al., 1991).
Nevertheless, we do not agree with Suyanto and Watts (2002), that specimen MZB 12716 represents P. theodorverhoeveni. MZB 12716 is a young animal - on the basis of the photograph (o.c., fig. 1) we would place it in wear stage 1 - and therefore, most diagnostic characteristics of P. theodorverhoeveni should be easily visible. MZB 12716 does have an anterocentral cusp on m1, as does 10% of our P. armandvillei material and 21% of our P. theodorverhoeveni material. According to Suyanto and Watts (2002), an anterolabial and posterolabial cusplet are also present on m1. However, we cannot recognize the presence of either cusplet from the photograph they provide, and in our experience the posterolabial cusplet is almost invariably clearly present in young P. theodorverhoeveni (it is present in 95% of our wear stage 1 P. theodorverhoeveni material). MZB 12716 does not have an anterolabial cusp on m2 either. This cusp is present in all our wear stage 1 P. theodorverhoeveni material. According to Suyanto and Watts (2002), MZB 12716 is somewhat smaller than another Papagomys found in the MZB collection. However, the molar breadth measurements they provide fall well within the range of variation in our P. armandvillei material, and well above even the largest specimens of P. theodorverhoeveni. In conclusion, all evidence suggests that MZB 12716 is not an example of P. theodorverhoeveni, but of P. armandvillei. K.M. Helgen, who has seen the specimen, kindly informed us that he had come to the same conclusion (Helgen, pers. comm. 2007). Therefore, P. theodorverhoeveni should still be considered an extinct species.