Eutetrarhynchus pacificus n. sp. (Cestoda: Trypanorhyncha) from Raja inornata Jordan & Gilbert (Batoidea: Rajiformes) off the coast of California with comments on congeners

Abstract

Eutetrarhynchus pacificus n. sp. is described from the spiral valve of Raja inornata Jordan & Gilbert off the coast of California, USA. The new species is distinguished from E. ruficollis (Eysenhardt, 1829) and E. leucomelanus (Shipley & Hornell, 1906) in having acraspedote rather than craspedote segments and a saccate rather than a branched uterus. It is distinguished from E. platycephali Palm, 2004 in lacking an enlarged hook in the eighth row of the basal armature and from E. beveridgei Schaeffner, 2013, which has a basal swelling and a distinctive basal armature. A partial redescription of E. ruficollis, the type-species of the genus, is provided based on available museum specimens, high..