Lenisaphelenchus ulomae n. gen., n. sp. (Rhabditida: Aphelenchoididae) isolated from the body cavity of Uloma marseuli Nakane (Coleoptera: Tenebrionidae) from Japan

Abstract

Summary A new aphelenchoidid entomoparasitic nematode was isolated from the body cavity of overwintering individuals of a tenebrionid beetle, Uloma marseuli, collected at Shiga, Japan. The nematode is characterised by its six equal-sized lips forming a dome shape continuous with body contour. It has a moderately thick stylet, with wide lumen, a long two-part long (conus + conophore) and elongate oval or pear-shaped metacorpus with glandular anterior part. The male spicules are separate with a well-developed condylus, triangular rostrum and smoothly and strongly curved calomus-lamina complex. A gubernaculum or apophysis is absent. There are two pairs of papilliform male genital papillae. Females lack a post-vulval uterine sac, have a seemingly vestigial rectum and anus, and conical tail. The combination of the typological characters of the species does not fit any currently accepted aphelenchoidid genus and is somewhat intermediate between the Ektaphelenchinae and Entaphelenchinae. The molecular phylogenetic analysis also suggested that the nematode is close to both Ektaphelenchoides (Ektaphelenchinae) and Peraphelenchus (Entaphelenchinae). Thus, the nematode is described and illustrated as Lenisaphelenchus ulomae n. gen., n. sp. and tentatively placed in the Ektaphelenchinae.