Cytological study of Rubenstrema exasperatum (Trematoda:Omphalometridae).

Cytological studies on Rubenstrema exasperatum were carried out. The number of chromosomes in diploid cells (2n = 16), and the morphological characteristics of the karyotype were determined. All the chromosomes (from Nos 2 to 8) had a well-defined short arm and, in accordance with the Ic values, were determined to be meta-submetacentric. Polymorphism was established in the length of the 2 homologues of the 1st chromosome. This pair is probably linked with sex determination.