(Schreber, 1774)
Greater Horseshoe bat
External characters (Table 26)
This is a medium-sized Rhinolophid bat, with a forearm length averaging 58.9 mm (54.8-62.1 mm). The sella of the noseleaf is relatively small. When viewed from in front, its anterior border is narrow above and widened below but not massively as in the R. trifoliatus group. The superior connecting process is bluntly rounded off when viewed from the side (Fig. 73). The horseshoe is relatively narrow and does not cover all the muzzle (Rfe3). The lancet is narrowly pointed and has concave sides. In the wing, the third metacarpal is characteristically short, averaging 10.4% (8.1-14.0%) less than the fourth metacarpal and 13.1% (9.0-16.0%) shorter than the fifth. In contrast, the first phalanx of the third metacarpal is relatively long, exceeding half the length of the metacarpal; in R. rouxii and R. affinis , it is less than 40% of the length of the third metacarpal. The pelage is long, soft and dense, not conspicuously woolly as in R. luctus (Rlu1). In one of the local races R. f. proximus , it is usually a uniform light greyish or drab brown above with the paler hair bases showing through in places. The ventral aspect is a lighter, buffy brown. Immature specimens are greyer than the adults. The baculum has a flattened shaft that is expanded in dorsal view; it is constricted above the base which has two basal lobes (Fig. 62). The mean length is about 3.7 mm and the greatest width about 0.9 mm (Thomas, in prep.).
Cranial characters
The skull is robust with a condylo-canine length averaging 21.5 mm (19.7-22.3 mm). The zygomata are widest opposite their roots; they exceed the braincase in breadth. The rostrum is elevated and forms a pronounced nasal bulb. There are four swellings with the lateral ones less developed; the median ones are almost circular in outline. The sagittal crest bifurcates anteriorly forming the posterior margins of a shallow nasal pit. The postorbital constriction is narrow. Lambdoid crests are present laterally. The supraoccipital and foramen magnum are directed downwards and only slightly backwards. The palate is deeply emarginated anteriorly, almost to the mid-point of M1. Posteriorly, it is emarginated to the level of the metastyle of M2. The anterior margin of the mesopterygoid space is relatively narrow when compared to that of R. affinis or R. rouxii . The tympanic bullae are small and cover less than half of the large cochleae. The coronoid process of each half mandible, like that of R. rouxii (Fig. 66), is low and bluntly pointed; its anterior surface is nearly vertical. The angular process is heavily ridged on its infero-lateral surface.
Dentition
- Upper toothrow length (C-M3) averages 9.1 mm (8.5-9.6 mm). The upper incisor (I2) is very small; its crown is expanded into a broad cutting surface. The upper canine is powerful and very broad in relation to its height, with a well developed cingulum, which usually overlaps that of the second premolar (PM4); there are no cingular cusps. The first upper premolar (PM2) is sometimes absent, when present it is minute, smooth crowned, and displaced externally from the toothrow; it is situated in the angle between the canine and second premolar (PM4) (Fig. 61b). PM4 is powerful, it attains three-quarters the height of the canine. M1 slightly exceeds M2 in size; it has a weak protocone and a small hypoconal flange; the parastyle and metastyle are better developed than the mesostyle. M3 is half to two-thirds the size of M2; it lacks a metastyle and most of the final commissure.
- The lower incisors are trifid and closely grouped together; the second (i2) is larger than the first (i1). The lower canine is more slender than upper; its posterior surface is concave, its cingulum without cusps. The first lower premolar (pm2) is half the height and crown area of third (pm4), with which it is in contact (Fig. 61b). The second premolar (pm3) is usually absent; when present, it is minute and displaced externally from toothrow, it lies in the angle between the cingula of pm2 and pm4. pm4 is robust; it is three-quarters the height of the canine. m1 and m2 are equal in size; the protoconid is outstandingly higher than the other cusps. m3 is smaller than m2 with its talonid narrower. In all three lower molars the cingulum forms a minute accessory cusp behind the entoconid.
Variation
Specimens from Himachal Pradesh and Nepal east to Nagaland and Arunachal Pradesh are referrable to R. f. tragatus . They tend to be large with the forearm exceeding 60 mm; the pelage colour is usually (but not always) dark, a deep chestnut brown (Rfe1, Rfe4). The taxon regulus is a synonym of tragatus . Specimens from Baluchistan, northern Pakistan and Kashmir are usually paler and smaller with a forearm length of between 53 and 59 mm (Chakraborty, 1977) and are referable to R. f. proximus .