[Redescription of the species of Calyptrobothrium Monticelli, 1893 (Tetraphyllidea: Phyllobothriidae) parasites of Torpedo marmorata in Torpedo nobiliana (Elasmobranchii: Torpedinidae)].

A study of the cestodes from the intestinal parasites of torpedinid elasmobranchs off the coast of Algeria, revealed the presence, in Torpedo marmorata Risso, of a species of Calyptrobothrium Monticelli, 1893, which we believe is identical to C. riggii Monticelli, 1893. This species, which has not been re-examined since its original description, is redescribed. We consider that the cestode from T. marmorata, described by Zschokke (1888) under the name of Tetrabothrium longicolle Molin, 1858, is conspecific with C.riggii. In Torpedo nobiliana Bonaparte, from the Mediterranean, we found C. occidentale Linton, 1900 and C. minus Linton, 1907. These two species are redescribed based on the type-material from the North American Atlantic coast, as well as from specimens collected off Sète and Algeria. We place several specimens, previously identified as C. riggii, as conspecific with C. minus. An amended diagnosis for Calyptrobothrium is proposed. We discuss the attribution of Bilocularia hyperapolytica Obersteiner, 1914 from Centrophorus granulosus (Centrophoridae) to Calyptrobothrium. C. chalarosomum Alexander, 1963 from Cephaloscyllium isabellum (Scylliorhinidae) off New-Zealand is excluded from the genus and placed close to Crossobothrium Linton, 1889.