Karyological Analysis and Morphometrics of Horsfield's Bat, Myotis horsfieldii (Chiroptera, Vespertilionidae)

Abstract

Karyological analysis and morphometrics of Horsfield's bat (Myotis horsfieldii) from Thailand were studied. Blood samples were taken from five male and five female bats. After standard whole blood lymphocytes were cultured at 37°C for 72 h in presence of colchicine, metaphase spreads were performed on microscopic slides and air-dried. Conventional staining and GTG-banding techniques were applied to stain the chromosome. The results showed that the diploid chromosome number of M. horsfieldii was 2n=44, the fundamental number (NF) was 52 in both male and female. The types of autosomes observed were 6 large metacentric, 4 medium telocentric, 2 small metacentric, 2 small submetacentric, and 28 small telocentric chromosomes. The X chromosome was a large submetacentric chromosome and the Y chromosome was a small acrocentric chromosome. From the GTG-banding technique, the number of bands and location in M. horsfieldii was observed to be 195, and each chromosome pair could be clearly differentiated. Six external morphological characters were measured as well as 13 cranial and dental measurements. The karyotype formula of M. horsfieldii is as follows:
2n (44)=L^m₆+M₄^t+S^m₂+S₂^sm+S₂₈^t+XY