STUDIES ON THE SCOLEX MORPHOLOGY OF EUBOTHRIUM SPP WITH EMPHASIS ON CHARACTERS USABLE IN SPECIES DISCRIMINATION AND WITH BRIEF REFERENCES ON THE SCOLICES OF BOTHRIOCEPHALUS SP AND TRIAENOPHORUS SPP (CESTODA, PSEUDOPHYLLIDEA)

Scolices of Eubothrium crassum from brown trout, E. salvelini from char, E. parvum from mallotus, Bothriocephalus sp. from three-spined stickleback, and Triaenophorus spp. from pike were studied using scanning electron microscopy (S.E.M.) and light microscopy, only the two first mentioned species were sectioned for transmission electron microscopy (T.E.M.). All scoleces examined with S.E.M. were characterized by 'spherical bodies' appearing on the scolex surface. Studied with T.E.M. these 'bodies' turned out to be cytoplasmic protrusions containing secretory granules. These protrusions seemed to be nipped off as globular structures which freed single secretory granules. The present study also emphasizes the use of S.E.M. as a tool in cestode taxonomy and clarifies some of the problems and confusion that have surrounded the scolex morphology and shape of E. crassum and E. salvelini. © 1979 Springer-Verlag.