Rhinolophus simplex, 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 : 76-79

. Rhinolophus simplex , sp. n.

(Plate III. fig. 1.)

Diagnosis. Cranial character: supraorbital crests meeting at a point behind the middle of the orbit. External: sella distinctly constricted at middle. Forearm 44'2 mm.

Details. Nose-leaves larg (Rh. truncatus, nanus ). A supplementary leaflet distinctly visible in front of, and on the anterior part of the sides of, the horseshoe; a character common to all the members of the present group, but becoming gradually less pronounced in the more highly developed species ( affinis , ferrum-equinum , and their allies); it seems to point back to the much more primitive genus Hipposiderus. Horseshoe so broad as to completely cover the upper lip; a slight indication of a tooth-like projection on either side of the median notch. Sella decidedly broader at base than at summit, and distinctly constricted at middle; summit rounded; height of sella, from angle between vertical portion and nasal lobe, about 4'8 mm., width at base 2’3, at constriction 1'9, at summit, 1‘8 mm.; front of sella densely covered with exceeclingly short white hairs (scarcely observable without a lens). Posterior con­ necting process low and broadly rounded off. Lancet long, almost cuneate; length, from posterior transverse bridge, about 4‘7 mm. Three mental grooves, as in all forms of this group, except the highest-differentiated species ( ferrum-equinum and its nearest relations). Ears, compared with those of the closely allied Austro-Malayan species, rather large, almost reaching the tip of the muzzle when laid forwards. Upper part of outer margin somewhat concave; tip blunt; no constriction below the tip. Wing-structure very primitive: 4th and 5th metacarpals sub­ equal in length (the 5th, if anything, a little shorter), and both of them but very slightly longer than 3rd; III.'2 * less than 11 the length of III.1; IV.2 and, especially, V.2 very short, being only a trifle longer than IV.1 and V.1 This structure of the wing is characteristic of all the primitive members of this group { simpleX , megaphyllus , truncatus, nanus , celebensis , borneensis , malayanus , rouXi , &c.); it is first in so highly-developed forms as affinis and its various modifications ( ferrum-equinum , &c.) that we find an important progress: prolongation of III.2; shortening of the 3rd metacarpal, as compared with the 4th and 5th; the 5th meta­ carpal decidedly longer than the 4th; &c.

Tail a little longer than the lower leg. Plagiopatagium inserted on tarsus.

Colour (of a spirit-specimen, unfaded). Fur of upper side a very dark shade of “ drab,” approaching “ Prout’s brown ”; base of hairs rather more distinctly drab; under side somewhat darker than drab.

Skull. Four anterior nasal swellings and two posterior. The four anterior arranged in a transverse row, forming the upper and lateral borders of the nasal opening. Externally these anterior swellings are separated only by extremely faint lineai’ depressions; internally by three bony lamella?, also easily observable through the thin, transparent outer wall of the swellings. The posterior nasal swellings, situated immediately behind the anterior ones, at the front corner of the orbital cavity, are much lower, slightly concave at summit; three very faint lines divide them, rather indistinctly, into an upper, middle, and lower swelling.—The shape and arrangement of the nasal swellings, as here described, are, roughly speaking, the same in almost all the members of the simpleX- group; there is some variation in the size of the swellings in the different species; but the more noteworthy deviations from the general scheme are two only: Rh. malayanus and Rh. stheno .

Postnasal depression triangular in shape, rather long; the supraorbital crests, which constitute the lateral border of this depression, meeting (and joining the sagittal crest) at a point more or less behind the middle of the orbital cavity. “ Supraorbital length ” of skull (i. e. distance between the point of junction of supraorbital crests and median anterior point of nasal swellings) greater’ than extreme width of nasal swellings.—The shape of this part of the skull, as here described, is characteristic of only the four most primitive members of the group ( simpleX , mega- phyllus, truncatus, nanus ).

Palatal bridge comparatively long (in anteroposterior direction); measured in the median line equal to about one-third the length of the upper tooth-row; median anterior point opposite the front of m1, median posterior point opposite the middle of m2.

Dentition. As a general guidance: in all existing species of the genus the upper p3 * is completely lost; in all the more primitive Sııecies of the sín27e›Zeœ-_£¿1*0111) also the lower D. is Very 11111011 reduced) species of the simplex-group also the lower p3 is very much reduced in size and on point of being driven out of the tooth-row, to the external side; in all the more primitive species of the group also the upper p 2 is reduced in size, but still, invariably, in the

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tooth-row.Jwing" rennu-ks apply to Rh. 31712271160; and R/z. mega-phy/Zlzas, the The following remarks apply to Rh. simpleX and Rh.. megaphyllus , the dentition of these two species, the most primitive within the present group, being practically exactly alike:—p3 very small, but decidedly less reduced than in the other species of the group. The position of this tooth, in relation to p, and p4, varies individually (in the same geographical race, and in examples from the same locality and of apparently the same age): completely in the tooth-row (one specimen), or slightly towards the external side (two), or half external (one), or almost quite external (one), or completely external (one). This “ vacillation ” in the position of p3 is of some interest as being the first indication of a tendency towards driving this premolar out of the tooth-row, a tendency gradually increasing in a long series of more highly developed species, and culminating in the forms in which the tooth is quite lost, even in young individuals ( Rh. acrotis ). —p2 is comparatively large, with a ■ well-developed, pointed cusp. From its base to its tip this cusp is directed obliquely inwards, under an angle of about 25° to 45° with the vertical line; also in those species of the present group in which the cusp is so much reduced as to be scarcely perceptible without a lens, it is invariably pointing obliquely inwards, only to a still higher degree. The upper canine and p' * * always widely separated. In some individuals there is a very narrow interspace between p2 and p4, on either side of the jaw, or on one side, no doubt a remnant of the place where p 3,

lost in all existing species, was situated (see footnote on p. 77). Measurements *. On p. 80.

Type. ♀ ad. (in alcohol). Lombok, 2500 ft., June 1896. Col­ lected by A. Everett, Esq. Brit. Mus. no. 97.4.18.4 .