Pelopscreadium aegyptense n. gen., n. sp. and Pelopscreadium spongiosum (Bray & Cribb, 1998) n. comb., (Digenea: Lepocreadiidae), each from disjunct populations of the Yellow boxfish, Ostracion cubicus Linnaeus (Ostraciidae)

Abstract

Bianium spongiosum Bray & Cribb, 1998 (Lepocreadiidae), described from the yellow boxfish, Ostracion cubicus Linnaeus (Ostraciidae), off Lizard Island, Queensland, Australia, possesses a combination of the following three morphological features which distinguishes it from all the other species currently assigned to the genus: (1) large internal patches of large cells forming sponge-like pads we have termed "pelops"("pelop" sing.) laterally in the forebody extending from near the anterior extremity to about the level of the intestinal bifurcation rather than possessing a scoop; (2) ceca that reach to near the posterior extremity where they end blindly without ani; and (3) a vitellarium which is present laterally but not dorsal to the ceca. Based on this we propose the erection of Pelopscreadium n. gen. (Lepocreadiidae) with the assignment of B. spongiosum to this new genus as the type-species, Pelopscreadium spongiosum (Bray & Cribb, 1998) n. comb. Pelopscreadium aegyptense n. sp., also from the yellow boxfish but from the Red Sea off Sharm El-Naga, Egypt, is described as the second member of the new genus because it shares these three characteristics with P. spongiosum.

An Anomalous Phylogenetic Position for Deraiotrema platacis Machida, 1982 (Lepocreadiidae) from Platax pinnatus on the Great Barrier Reef

“…Notably, none of these have multiple testes although the first three genera have caeca abutting the body wall, possibly forming ani. Other genera have a similar arrangement of the caeca, but no body-flaps, i.e., Pelopscreadium Dronen, Blend, Khalifa, Mohamadain & Karar, 2016 and Mobahincia Bray, Cribb & Cutmore, 2018 [3,27], neither of which have multiple testes. Diploproctia Mamaev, 1970 was illustrated with a scoop by Bray [26], but Machida [28] redescribed the type-and only species D. drepanei Mamaev, 1970 showing that Bray's interpretation of the illustration in Mamaev [29] was in error and the species lacks a scoop.…”

Apharyngogyliauchen callyodontis Yamaguti, 1942 (Digenea) from a New Host, the Common Parrotfish, Scarus psittacus (Scaridae) with Special Reference to its Morphological Intra-SpecificVariations

“…Wang (1977) recognized Gyliauchen thalassamae from the Sixbar wrasse, Thalassoma Hardwicke], off China Sea and characterized it from the other Gyliauchen spp. by its long ceca and absence of the oesophageal bulb (= "pharynx" of Wang [1977]) and on the basis of the later feature, Hall & Cribb (2005) investigations reassigned G. thalassamae Wang, 1977 inside Apharyngogyliauchen as Apharyngogyliauchen thalassamae (Wang, 1977) Hall & Cribb, 2005 As part of an on-going study of the Digenea parasitizing the Red Sea fishes (see Khalifa et al, 2015;Dronen et al 2016;Blend et al 2017;Khalifa et al, 2018), A. callyodontis Yamaguti, 1942 was redescribed and its comparative metric account by several authors is also given and discussed.…”