Abstract
Male meiosis in 6 species of the sarcophagid genus Parasarcophaga-P. misera, P. albiceps, P. argyrostoma, P. orchidea, P. ruficornis and P. knabi-was investigated with a view to obtain information regarding the degree of homology betweeen the X and Y chromosomes. Both autosomal as well as the sex bivalents are achiasmate in all the six species. The X and Y chromosomes in all the species, except P. knabi, show a close side by side association right from prophase I to metaphase I. In P. knabi, the extremely long X and Y chromosomes are spatially separate on emergence from the resting nucleus at prophase I and do not show close association at metaphase I. The role of C-band positive heterochromatic material in the pairing of X and Y chromosomes during first meiotic prophase has been discussed.
