Characterization of the karyotype of proasellus meridianusby differential staining techniques

The genome of Proasellus meridianus (2 n= 10) contains two kinds of constitutive heterochromatin: one, polymorphic and stainable with Chromomycin A3 located on certain telomeres, and the other centromeric and stainable with Hoechst 33258, visible only at pachytene. The NORs stainable with silver nitrate are terminal and located on at least three pairs of chromosomes. In diakinesis and first meiotic metaphase, usually the silver technique differentially stains the centromeric area of only one of the two sister chromatids of each homologue. This indicates a direct relationship between silver staining and kinetochore function. Surface spread of testicular tissue displays five synaptonemal complexes which are homogeneous throughout their length