Helminth parasites from Red Sea fishes: Neowardula brayi gen. nov., sp. nov. (Trematoda: Mesometridae Poche, 1926) and Sclerocollum saudii sp. nov. (Acanthocephala: Cavisomidae Meyer, 1932) Author Al-Jahdali, Mohammed O. text Zootaxa 2010 2681 57 65 journal article 10.5281/zenodo.199330 96e80d1f-e569-4069-bd45-a28029a08aa1 1175-5326 199330 Sclerocollum Schmidt et Paperna, 1978 The acanthocephalan genus Sclerocollum was erected by Schmidt and Paperna (1978) for S . rubrimaris Schmidt et Paperna, 1978 from the intestine of three fish species ( Siganus rivulatus , S . rostratus and Pseudobalistes fuscus ) in the Gulf of Eilat, Red Sea. They referred the genus to the family Rhadinorhynchidae Travassos, 1923 and subfamily Gorgorhynchinae Van Cleave et Lincicome, 1940, differentiating it from Neorhadinorhynchus Yamaguti, 1939 by the conspicuous sclerotised plaques which are embedded in the tegument at the anterior region of the trunk (versus absent) and by the basal hooks of the proboscis which alternate with each other (versus arranged at the same level to form a ring). These two characteristics were also observed by Schmidt and Paperna (1978) in the original specimens of Neorhadinorhynchus robustus (Edmonds, 1964) Golvan, 1969 (from Siganus lineatus on the Southern Great Barrier Reef). Therefore, they transferred this species to Sclerocollum as a new combination. In their revision of the family Diplosentidae Tubangui et Masiluñgan, 1937 , Pichelin and Cribb (2001) transferred Neorhadinorhynchus and Sclerocollum to family Cavisomidae Meyer, 1932 , and on the basis of a striking similarity, they considered them as synonyms of Diplosentis Tubangui et Masiluñgan, 1937 . Accordingly, all species of Neorhadinorhynchus and Sclerocollum were transferred by Pichelin and Cribb (2001) to Diplosentis as new combinations. Hassanine (2006) agreed with Pichelin and Cribb (2001) in transferring Sclerocollum to family Cavisomidae , but retained it as a valid genus, stating that in its members, the basal hooks of proboscis alternate with each other (not forming ring), a character lacking in Diplosentis and its synonym, i.e. Neorhadinorhynchus , where the basal hooks of proboscis are at the same level and forming a ring. Accordingly, 2 species of Sclerocollum are currently recognized, i.e. S . rubrimaris Schmidt et Paprena, 1978 ( type species) and S . robustus (Edmonds, 1964) Schmidt et Paprena, 1978 .