[Heterotylenchus simplex sp. n. (Nematoda, Sphaerulariidae)--a parasite of the zoophilic fly Morellia simplex Lw].

A new species of nematodes, Heterotylenchus simplex spn n., was found in zoophilous flies of Morellia simplex caught from cows in the Bakhchisaray region of the Crimea. The above species differs from all known ones of the genus Heterotylenchus in the presence of the quadricolumella in parthenogenetic females and rudiment of the posterior uterine branch in gamogenetic females. H. simplex is close in its biology and ecology to H. autumnalis and in its morphology - to H. aberrans.