Chromosome numbers for three species of medicinal leeches (Hirudo spp.).

Karyological preparations were made from the testisacs of three medicinal leech species Hirudo medicinalis Linnaeus, 1758, H. verbana Carena, 1820 and H. orientalis Utevsky & Trontelj, 2005 . The samples originated from different populations in Azerbaijan, Kazakhstan, Russian Federation, Ukraine and Uzbekistan. The chromosome numbers were determined both from mitotic and meiotic stages of spermatogenesis using the propionic haematoxylin staining technique. All three species were found to have different haploid chromosome numbers: H. medicinalis 14, H. verbana 13 and H. orientalis 12, thus corroborating the validity of these taxa. The chromosomes can be classified as meta-, submetacentric and acrocentric. The chromosome numbers obtained are similar to that of the related species Haemopis sanguisuga (Linnaeus, 1758), which has 13 pairs.