SUMMARY
Metaphase chromosomes of Artibeus lituratus, A. jamaicensis, A. cinereus and Phyllostomus discolor have been analyzed by C-banding and staining with base-specific fluorochromes for a better characterization of constitutive heterochromatin. Slides pretreated for C-banding and stained with DAPI/DA (CB-DAPI) have shown a pattern similar to that obtained by C-banding (CBG) for the above species. CB-CMA3 staining evidenced telomeric blocks in the short arms of some chromosomes and in the long arm of the Y1 in A. lituratus and A. jamaicensis. In P. discolor, however only R-banding pattern was visualized. Triple staining CMA3/DA/DAPI revealed R-banding pattern in all these species, and only in P. discolor was possible to detect small DAPI-positive blocks in the pericentromeric regions. Sequential staining AgNO3/CMA3/DAPI revealed that the nucleolar organizer regions in A. lituratus and A. jamaicensis are CMA3 positive and DAPI neutral. On the other hand they are CMA3 neutral in P. discolor.