Cytogenetic studies on Choeroniscus minor (Chiroptera, Phyllostomidae) from the Amazon region.

The Choeroniscus genus (Glossophaginae, Phyllostomidae) has five monotypic species: C. minor, C. godmani, C. intermedius, C. inca and C. periosus. This paper analyses the karyotype of a female C. minor, collected close to the Guama river (Belém, Para, Brazil). G-, C-banding and NOR-staining were performed. This species has 2n = 20 chromosomes, where there are two bi-armed pairs (numbers 1 and 9) and seven subtelocentric pairs (2, 3, 4, 5, 6, 7 and 8). The probable X chromosome is a submetacentric. The constitutive heterochromatin can be found in the short arm of five subtelocentric pairs (4, 5, 6, 7 and 8) and is centromeric in the bi-armed pairs numbers 1 and 9, and the X chromosome. The heterochromatic bands are heteromorphic in three pairs (1, 2 and 3). Active NOR were observed in the short arms of eight subtelocentric chromosomes, suggesting that at least four pairs are nucleolar organizers. This paper describes for the first time the karyotype of C. minor from the Amazon region.