Hapalorhynchus rugatus sp.nov. (Digenea: Spirorchiidae) from a Malaysian freshwater turtle

A new species of Hapalorhynchus collected from a Malaysian soft-shelled turtle, Trionyx cartilagineus, most closely resembles H. lyssimus from an Indian soft-shelled turtle by having vitelline follicles restricted to the hindbody and by having lateral muscular papillae on the body, traits no other species of Hapalorhynchus possesses. The new species differs from H. lyssimus by lacking an expanded hindbody and possessing a relatively smaller cirrus sac, lobate rather than smooth testes, and body papillae restricted to the hindbody rather than extending into the forebody and which are fewer in number than those present on H. lyssimus. Coeuritrema macrotesticularis is transferred to Hapalorhynchus and a key to members of Hapalorhynchus is provided.