A New Criconematid Nematode, Pseudocriconema japonicum n. gen. et n. sp. (Tylenchida : Criconematidae) from Japan

Abstract

The designation Pseudocriconema n. gen. is proposed with a type species of P.japonicum n. sp. for the nematode from soil around roots of Pieris japonica, Hydrangea paniculata, and Lindera triloba in Mt. Aso, Kumamoto Prefecture. This genus resembles Seriespinula, but differs from it in the distinct submedian lobes, and tri-and/or rectangular shaped body scales. This is also similar to the Ogma, but distinguished from it by the larger first-head-annule and body scales with fringes on extremities. The type species, P.Japonicum is characterized by 400-504 μm body length, ten longitudinal rows of scales, 77-90 body annules, stylet 63.2-69.5 μm long, and vulva located at the 15th to 18th annule from the terminus. Male has three incisures in the lateral field, acute and 46.0-54.0 μm long spicules, and a small gubernaculum. Third-and fourth-stage juveniles have 10-12 longitudinal rows of round scakes with fine and sharp spines on their tip.