SYSTEMATIC REVISION OF OMPHALOMETRA-FLEXUOSA (DIGENEA, PLAGIORCHIATA)- RELATIONSHIP WITH OPISTHIOGLYPHE, LECITHOPYGE AND PLAGIORCHIS GENERA

The cercarial chaetotaxy is used for a systematic revision of a group of Trematoda Plagiorchiata belonging to the genera Omphalometra, Opist hioglyphe, Neoglyphe, Lecithopyge and Plagiorchis. In the precedent ta xonomies, these genera have been attributed, either all to the Plagior chiidae, or, ones of them to the Omphalometridae, a part to the Prosth ogonomidae and the others to the Plagiorchiidae. The sensillae which h ave the most important value for systematics are the CI, CII, CIIII ce phalic ones, AID antero-dorsal, SI, SII acetabular and U caudal ones. According to our data, the five concerned genera can be divided into f our groups: Opisthioglyphe ranae which displays 7 CI, 2-2 1/2 CII, 1 C III1, 8 AID, 9 SI, 0-6 SII. Lecithopyge rastellus (= Opisthioglyphe ra stellus), O. locellus, O. megastomus which display 5 CI, 5 1/2 CII, 1 or 2 CIII1, 4 AID, 9 SI, 0 to 6 SII. Omphalometra flexuosa which displ ays 5 to 6 CI, 6 1/2 CII, 1 CIIII, 4 to 5 AID, 6-10 SI, 0-3 SII. Plagi orchis spp. (10 species) which display 5 CI, 6 1/2 CII, 2 CIIII, 3-7 A ID, 9 SI, 6 SII. Our results show the heterogeneousness of the genus O pisthioglyphe in the acception Of Yamaguti (1971) and Skrjabin (1971); the type species being Opisthioglyphe ranae, the rastellus, locellus and megastomus species display a very different chaetotaxic pattern an d can be assembled into the genus Lecithopyge Perkins, 1928 of which t he type species is L. rastellus. Our results suggest the existence of closely relation between the L. rastellus species (parasite of Amphibi ans) and the 0. locellus and megastomus species (parasites of Mammals) these two later species being attributed to the genus Neoglyphe Yamag uti, 1958 by the classical systematics. Our results allow the invalida tion of the genus Neoglyphe of which the type species is N. locellus; this species becomes a synonyme of a species of Lecithopyge. They conf irm the validity of the genus Plagiorchis and its homogeneousness whil e the classes of their vertebrate hosts include as well Amphibians and Reptiles, than Birds and Mammals. They allow the grouping of Omphalom etra, Lecithopyge and Plagiorchis in the sub-family Plagiorchiinae mea nwhile Opisthioglyphe belongs to the Opisthioglyphinae.