The first chromosome study of the genera Calchas Birula, 1899 and Neocalchas Yagmur, Soleglad, Fet & Kovarik, 2013 (Scorpiones: Iuridae)
Abstract
The chromosomes of two species belonging to the scorpion family Iuridae are studied for the first time. Both analysed species displayed achiasmatic meiosis and no morphologically differentiated sex chromosomes; these features are typical for all scorpions.
Both species possessed monocentric chromosomes, a characteristic specific to the entire parvorder Iurida. The karyotype of Calchas nordmanni Birula, 1899 is composed of 82 chromosomes, and the diploid number of chromosomes in Neocalchas gruberi is 40.
Despite this conspicuous difference in 2n chromosome morphology is mainly acrocentric. Both species possess two pairs of the 18S rDNA clusters identified by FISH.
A higher number of rDNA loci may represent an ancestral state for the parvorder Iurida.