[Triploidy in populations of three species of black flies of the genus Prosimulium roubaud (Diptera, Simuliidae)].

Karyotypes of 94 larvae belonging to species of black flies of the genus Prosimulium Rouband were studied on aceto-orcein stained squashes of 94 larvae belonging to three species of Prosimulium: P. isos Rubzov, P. pecticrassum Rubzov, and P. pamiricum Chubareva et Petrova. All the larvae appeared to be triploid parthenogenetic females, with no males being found. The structural peculiarities of these polytene chromosomes suggest a heterozygous nature of the examined larvae.