Chromosomes of: A, B. Paraplangia sinespeculo and; C, D. Orophus cf. tessellatus stained using different techniques: C-banding (A, C), silver staining (B), and FISH with both 18S rDNA (green) and telomeric DNA (red) probes (B – left corner and D). Diakinesis and the insert in the left corner mitotic large chromosome (A), diplotene and FISH with 18S rDNA in the left corner mitotic chromosome (B): arrows and the insert chromosome demonstrated distally located thin C-band and single NOR coincide with cluster of 18S rDNA on the first pair of autosome. Arrows in spermatogonial (C) and female metaphases (D) indicate near paracentromeric located C-bands and 18S rDNA loci on the fourth pair of chromosomes. X indicates sex chromosome.