BANDED KARYOTYPES OF 11 SPECIES OF AMERICAN BATS (GENUS-MYOTIS)

The vespertilionid bat genus Myotis is among the most speciose of mammalian genera. It is comprised of some 68 species (Anderson and Jones 1967) and is found on virtually all major land masses of the world and in a wide variety of ecological situations. These bats are mostly insectivorous although at least one, Myotis (Pizonyx) vivesi,is a fish eater. Although there is a considerable volume of literature on the ecology, natural history, and behavior of the members of this genus, the systematic and phylogene tic relationships of many of the species remain poorly understood. Miller and Allen’s (1928) revision is still the most complete work available for American Myotis. More recently LaVal (1973) has revised the Neotropical species, and Findley (1972) studied phenetic relationships on a world-wide basis. Karyotypic studies have failed to shed much light on intrageneric relationships due to the conservative nature of the Myotis karyotype in that all speciesstudied to date appear to possess 2n=44. This paper reports the chromosomal banding patterns for approximately two-thirds of the recognized species of Myotis that occur in North America. Standard karyotypes have been reported for nine species used in this study: M. sodalis, M. grisescens, M. austroriparius, M. yumanensis, M. velifer, M. keenii, M. evotis, M. thysanodes, and M. nigricans (Baker and Patton 1967). The karyotypes of M. auriculus and M. keaysi are reported for the first time. In addition, the karyotypes for males of M. thysanodes and M. keenii have not been recorded previously. Chromosomal variation and its phylogenetic significance is discussed and a system of nomenclature for the banded chromosomes of vespertilionids is presented. © 1979, Japan Mendel Society, International Society of Cytology. All rights reserved.