Allopodocotyle enkaimushi n. sp (Digenea: Opecoelidae: Plagioporinae) from the Short-Tail Grenadier, Nezumia proxima (Gadiformes: Macrouridae), from Sagami Bay, Japan, with a Key to Species of This Genus and a Checklist of Parasites Reported from This Host
Academic Article
Overview
Research
Identity
Additional Document Info
Other
View All
Overview
abstract
2015 The Helminthological Society of Washington. Allopodocotyle enkaimushi n. sp. (Opecoelidae: Plagioporinae) is described from the pyloric ceca and intestine of the short-tail grenadier, Nezumia proxima (Smith and Radcliff, 1912) (Gadiformes, Macrouridae), collected at depths of 681-1,061 m off Jogashima Island, Sagami Bay, Japan. The new species is placed in Group C and is distinguished from its closest congener, Allopodocotyle margolisi Gibson, 1995, by possessing a terminal rather than a subterminal oral sucker; an unspecialized, inconspicuously elevated ventral sucker rather than being embedded in a well-developed ventral eminence that forms an anterior and lateral fold but with no distinct, muscular fold around the entire ventral sucker; a cirrus pouch that is entirely anterior to the ventral sucker rather than extending posteriorly to about the midlevel of it; and a sessile genital pore that is not situated on an eminence and surrounded by a muscular thickening of the body wall that appears to form a sphincter, as is the case in A. margolisi. In addition, A. enkaimushi n. sp. parasitizes a member of the grenadier genus Nezumia Jordan, 1904, from the west Pacific Ocean (Japan) rather than a species of the grenadier genus Coryphaenoides Gunnerus, 1765, from the North Atlantic Ocean. The combination of tandem testes, an entirely pre-acetabular cirrus pouch, and a pre-bifurcal (esophageal level) genital pore distinguishes A. enkaimushi n. sp. from all members of Group C recognized herein as well as from the 3 accepted species of Allopodocotyle Pritchard, 1966, already known from Japanese waters. A checklist of parasites reported from N. proxima is provided. We also furnish a key to the species in Groups A-C of Allopodocotyle, offer insights into the host familial diversity of shallow-water representatives in this genus, and hypothesize life histories for the 2 deep-water representatives in this genus.