Myotis sp.

Popov, Vasil V., 2004, Pliocene small mammals (Mammalia, Lipotyphla, Chiroptera, Lagomorpha, Rodentia) from Muselievo (North Bulgaria), Geodiversitas 26 (3), pp. 403-491 : 433

Myotis sp.

MATERIAL EXAMINED. — 2 fragments of mandible with m1-m3 and m3 (Ms346-347), 2 m 1 (Ms348), 1 p4, 1 m3 (Ms379-1, 2).

MEASUREMENTS. — See Table 5.

DESCRIPTION AND COMPARISONS

Mandible: the foramen mentale is located between c1 and p2.

m1-m2: these myotodontic molars are relatively short and wide as compared with the modern M. emarginatus , but not so much as in M. nattereri .

m3: as a whole this tooth is somewhat more elongated than in the modern M. nattereri , especially well pronounced in the talonid length, and the trigonid is less compressed anteroposteriorly.

REMARKS

The size of the remains under study is comparable with some recent medium-sized mouse-ear bats, such as Myotis emarginatus , M. nattereri , and to a lesser extends with M. capaccinii . The last species, however, is under the range of variability of the fossil form in some dimensions. The remains from Muselievo differ from the modern M. emarginatus in having not so elongate and generally smaller p4. They show a greater similarity with M. nattereri but the modern comparative material has more gracile upper canines.

A wide range of fossil forms of comparable size is known from the Pliocene and early Pleistocene of Europe ( Heller 1936; Topál 1983; Godawa 1993). In some measurements, the scarce remains from Muselievo fall in the upper range of variability or above it, of Myotis exilis Heller, 1936 , M. janossyi Topál, 1983 and M. danutae Kowalski, 1956 from Podlesice ( Poland) and Osztramos 9, 13 ( Hungary) ( Topál 1983; Godawa 1993). They are nearly identical with Myotis delicatus Heller, 1936 , and especially with the population of this species from Podlesice ( Poland) ( Godawa 1993). However, according to Kowalski (1956), the p 4 in the Polish population, described initially as Myotis dasycneme subtilis Kowalski, 1956 , is almost squared (0.70 × 0.75 mm). At the same time the only available p4 from Muselievo is clearly elongated ( Table 5). The fossil forms mentioned above show well pronounced differences in the height of coronoid process. Unfortunately the scarce and fragmentary material from Muselievo does not permit detailed comparisons. Therefore, I refrain from a conclusive determination until complete mandibles will be known.