Karyological studies of two japanese noctule bats (Chiroptera)

Abstract

Karyological investigations of two Japanese Nyctalus species were made based on G- and C-banding pattern analysis. The karyotype of N. furvus (2n = 44, FN = 50) was similar to the standard karyotype of Myotis species. On the other hand, the karyotype of N. lasiopterus aviator (2n = 42, FN = 50) was characterized by having an additional large metacentric pair. By comparison of the G-banding pattern between the two Nyctalus species, it is clear that the metacentric pair of N. lasiopterus aviator has derived from the Robertsonian fusion of the two pairs (nos. 8 and 10) of N. furvus. There was also a significant difference in amount of constitutive heterochromatin between the two Nyctalus species. In N. furvus the additional heterochromatin was observed on the majority of autosomes, while in N. lasiopterus aviator a small C-band was restricted to the centromeric area of each autosome. Thus, the C-band pattern of N. lasiopterus aviator would be interpreted by assuming the decrease of heterochromatin in the course of its speciation from N. furvus. © 1982 Taylor & Francis Group, LLC.