Rhinolophus nanus, Andersen, 1905

Andersen, Knud, 1905, On some Bats of the Genus Rhinolophus, with Remarks on their Mutual Affinities, and Descriptions of Twenty-six new Forms., Proceedings of the Zoological Society of London 2, pp. 75-145 : 82-83

4. Rhinolophus nanus , sp. n.

(Plate III. fig. 3.)

Rhinolophus megaphyllus (non Gray), var. /3 (partim), Dolison, Cat. Chir. Brit. Mus. (1878) p. 111 (Goram).

Diagnosis. Essential cranial characters as in Rh. truncatus, but brain-case remarkably slender. Sella so slightly constricted as to be practically parallel-margined. Small: forearm 43'3 mm.

Details. This species marks a further step towards the celebensisborneensis type. Externally Rh. nanus is exceedingly like these two species, but the skull is of the simpleX type.

The sella (compared with that of the foregoing three species) is considerably reduced in breadth; its width at the base is but very little greater than at the summit; the constriction at the middle is much reduced (it requires some attention not to be overlooked); and the whole of the sella therefore might very well be called almost parallel-margined; summit completely square-cut (there will probably, in a large series, be some individual variation in this respect). The horseshoe, too, is a little narrower. Lancet almost cuneate, the lateral margins being but very slightly concave. The size of the ears, both length and breadth, is reduced; the tip slightly more attenuated (less blunt than in Rh. simpleX ).

In the structure of the wings it stands exactly on the same level as the foregoing species.

Colour (one skin; adult; teeth almost quite unworn).—Fur of the upper side uniform dull “ mars-brown ”; base of hairs slightly lighter; under side very much of the same colour as the upper side, but with a slight tinge of “ drab. ”

Skull. Postnasal depression and supraorbital crests as in Rh. simpleX . Nasal swellings very narrow (4'9 mm.). Chief character (compared with the three foregoing species): the very narrow brain-case (7 mm.).

Dentition. p3 quite external, and cingula of p „ and p(in contact (a sufficiently large series will presumably show some vacillation in the position of p3). p2 in the tooth-row; its cusp very small.

Measurements. On p. 84.

Type. Ad. (skin). Goram Island. Collected by Dr. A. R.

Wallace. Brit. Mus. no. 61.12.11.10.

Remarks. This species is readily distinguished from Rh. celebensis and Rh. borneensis by the different shape of the facial portion of the skull.

Dobson regarded the specimen here described, together with two others from N. Celebes (Menado), as a variety (“ ss ”) of Rh. megaphyllus , characterised chiefly by having “ the summit of the vertical process of the sella broadly rounded off, much broader than the base. ” But, firstly, it should be remembered that a sella, much broader at summit than at base, would be exactly the reverse of what is found in megaphyllus ; it would even be unique in the whole genus. Secondly, on resoftening the nose-leaves I found the sella, in all the three specimens, quite of the same general shape as in Rh. borneensis , i. e. practically

parallel-margined. It would evidently have been much more to the point if Dobson had called these Bats Rh. borneensis , not Rh. megapthyllus. But Rh. borneensis , again, was confused with Rh. minor, which, however, not only is a distinct species, but belongs to a different group of the genus.