Steinernema litorale n. sp. (Rhabditida: Steinernematidae), a new entomopathogenic nematode from Japan

Abstract

AbstractA new entomopathogenic nematode, Steinernema litorale n. sp., was isolated from sandy soils in Cape Irago, Atsumi Peninsula, Aichi, Honshu Island, Japan. The new species is characterised by the following morphological characters: infective third-stage juvenile with a body length of 909 ± 42.1 (834–988) μm, distance from head to excretory pore of 61 ± 3.3 (54–69) μm, tail length of 83 ± 4.5 (72–91) μm, ratio E value of 0.73 (0.68–0.83) and lateral field with nine distinct lines; male tail with a mucron in both generations, spicule shape (moderately arcuate, heavy, spicule with elongated manubrium), spicule length of 75 ± 4.8 (67–89) μm and gubernaculum length of 53 ± 4.0 (44–64) μm in the first generation male; female vulva with a double-flapped epiptygma and a tail with a pointed tip in both generations, and ratio D value of 45.2 (33.3–56.8) in the first generation female. The new species was distinguished from the morphologically similar species, S. feltiae, S. thanhi, S. karii, S. scarabaei, S. kraussei, S. oregonense, S. loci and S. diaprepesi by RFLP profiles. Morphological and molecular studies indicated that S. litorale n. sp. was phenotypically most similar to S. feltiae. However, cross hybridisation tests demonstrated that the two species were reproductively isolated.