Meiotic differences between three triatomine species (Hemiptera, Reduviidae)

Abstract

We have found the following differences in the male meiosis among three triatomine species: (1) The three largest autosomal bivalents of Triatoma infestans are heterochromatic. Rhodnius prolixus has two autosomal bivalents with heterochromatic blocks. Triatoma rubrovaria does not show any heteropycnotic autosomes. (2) Sex chromosomes in T. infestans form a chromocenter. At early prophase terminal associations are seen between sex chromosomes in T. rubrovaria, and they maintain a close association until diakinesis. An intimate association between the X and Y chromosomes is observed during early prophase in R. prolixus, but a distant association is maintained by the sex chromosomes at diffuse and diplotene stages in this species. (3) Polyploid nuclei of the nutritive cells are quite distinct. Numerous chromocenters of different shapes and sized are seen in those of T. infestans. In T. rubrovaria one chromocenter having two positively heteropycnotic elements is observed surrounded by homogeneous chromatin. Only one compact chromocenter is found amongst unevenly distributed chromatin, in R. prolixus. © 1985 Dr W. Junk Publishers.