Folia Parasitologica 39[4] 307-316 (1992)

BIOMETRIC VARIABILITY OF PROTEOCEPHALUS-NEGLECTUS (CESTODA, PROTEOCEPHALIDAE) IN 2 DIFFERENT AGE-GROUPS OF THE RAINBOW-TROUT FROM THE DOBSINA WATER RESERVOIR (EAST SLOVAKIA)

HANZELOVA V, SPAKULOVA M

HANZELOVA, V (reprint author), SLOVAK ACAD SCI, INST HELMINTHOL, HLINKOVA 3, CS-04001 KOSICE, CZECHOSLOVAKIA

The variability of 24 morphological characteristics in Proteocephalus neglectus La Rue, 1911, a parasite of the rainbow trout (Oncorhynchus mykiss (Walbaum)) was studied. Specimens of two morphologically clearly distinguishable types formed the metapopulation (hostophenote) of P. neglectus. The cestodes from type A (isolated from smaller, younger fish) were mostly no longer than 50 mm, the mature and gravid segments in almost all of them were more long than wide, contained small number of larger testes and an ovary with wide elliptic lobes. The cestodes from type B (isolated from larger, older fish) tended to be more than 50 mm long: the typical segment was extended in width, contained a large number of smaller testes and an ovary with narrow elongate lobes. The variability of morphological characteristics in P neglectus was found to be high; 35 % of the characteristics in helminths of group A and 55 % of the characteristics in helminths of group B showed a coefficient of variation > 20 %. The most stable characteristics in P neglectus were the number and diameter of testes, length and width of cirrus sac, length of ovarian lobe, diameter of vaginal sphincter and the number of uterine branches. The coefficient of variation for P neglectus egg also was rather low.

Published: December 1, 1992  Show citation