Canadian species of Merlinius Siddiqi, 1970 and a diagnosis and description for Mulveyotus hyalacus n. gen., n. sp. (Nematoda: Tylenchorhynchidae)

Abstract

Three new bisexual species of Merlinius Siddiqi, 1970, characterized by apically flattened heads and elongate–conoid tails with narrowly rounded or pointed ends, and a new genus and species (Tylenchorhynchidae) in Canada are described and illustrated. The distinguishing female characters of Merlinius plerorbus n. sp. are the constricted head, 16- to 17-μm-long stylet, 45- to 54-μm-long tail with 38–40 annules and a smoothly rounded terminus, and lobed spermathecae. Diagnostic for females of Merlinius circellus n. sp. are the continuous low head, 9- to 10-μm-long stylet, tail with 72–75 annules and a pointed terminus, and spherical spermathecae. The female of Merlinius tetylus n. sp. has a stylet length of 14 μm, a 98-μm-long tail with about 100 fine annules, and lobed spermathecae. Supplemental descriptive data for M. processus Siddiqi, 1979, a new species record for Canada, is provided, and included in a key to the species of Merlinius. Merlinius laminatus (Wu, 1969) Siddiqi, 1970 is transferred as a new combination to Scutylenchus Jairajpuri, 1971. Differential characters of Mulveyotus hyalacus n. gen., n. sp., are a body length of over 1 mm, alow, flattened continuous head, an areolated lateral field of three incisures, and a conoid tail over 100 μm long with a tapered smooth terminus of thickened cuticle comprising 24% of the tail length.