caa a22 4500 388112557 CHVBK 20180307125357.0 cr unu---uuuuu 161130e199901 xx s 000 0 eng 10.1017/S0022149X99000013 doi S0022149X99000013 pii (NATIONALLICENCE)cambridge-10.1017/S0022149X99000013 Scholz T. Institute of Parasitology,Academy of Sciences of the Czech Republic, Branišovská 31, 370 05 Ceské Budějovice, Czech Republic Life cycles of species of Proteocephalus, parasites of fishes in the Palearctic Region: a review [Elektronische Daten] [T. Scholz] The life cycles of species of Proteocephalus Weinland, 1858 (Cestoda: Proteocephalidea) parasitizing fishes in the Palearctic Region are reviewed on the basis of literary data and personal experimental observations, with special attention being paid to the development within the intermediate and definitive hosts. Planktonic crustaceans, diaptomid or cyclopid copepods (Copepoda), serve as the only intermediate hosts of all Proteocephalus species considered. A metacestode, or procercoid, develops in the body cavity of these planktonic crustaceans and the definitive host, a fish, becomes infected directly after consuming them. No previous reports of the parenteral location of metacestodes within the second intermediate host as it is in the Nearctic species P. ambloplitis have been recorded. Thus, the life cycles of Proteocephalus tapeworms resemble in their general patterns those of some pseudophyllidean cestodes such as Eubothrium or Bothriocephalus, differing from the latter in the presence of a floating eggs instead of possessing an operculate egg from which a ciliated, freely swimming larva, a coracidium, is liberated. The scolex of Proteocephalus is already formed at the stage of the procercoid within the copepod intermediate host; in this feature, proteocephalideans resemble caryophyllidean rather than pseudophyllidean cestodes. The morphology of procercoids of individual species is described with respect to the possibility of their differentiation and data on the spectrum of intermediate hosts are summarized. Procercoids of most taxa have a cercomer, which does not contain embryonic hooks in contrast to most pseudophyllidean cestodes. The role of invertebrates (alder-fly larvae — Megaloptera) and small prey fishes feeding upon plankton in the transmission of Proteocephalus tapeworms still remains unclear but these hosts are likely to occur in the life cycle. Data on the establishment of procercoids in definitive hosts, morphogenesis of tapeworms within fish hosts, and the length of the prepatent period are still scarce and new observations are needed. Whereas extensive information exists on the development of P. longicollis (syns. P. exiguus and P. neglectus), almost no data are available on the ontogeny of other taxa, in particular those occurring in brackish waters (P. gobiorum, P. tetrastomus). The morphology of P. cernuae and P. osculatus procercoids from experimentally infected intermediate hosts is described for the first time. Cambridge University Press Journal of Helminthology Cambridge University Press 73/1(1999-01), 1-19 0022-149X 73:1<1 1999 73 JHL https://doi.org/10.1017/S0022149X99000013 text/html Onlinezugriff via DOI 1 review-article jats NATIONALLICENCE 856 40 https://doi.org/10.1017/S0022149X99000013 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Scholz T. Institute of Parasitology,Academy of Sciences of the Czech Republic, Branišovská 31, 370 05 Ceské Budějovice, Czech Republic NATIONALLICENCE 773 0- Journal of Helminthology Cambridge University Press 73/1(1999-01), 1-19 0022-149X 73:1<1 1999 73 JHL CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge