Cryptaphelenchus fulvus n. sp. (Tylenchomorpha: Aphelenchoididae) isolated from Cryphalus fulvus Niijima (Coleoptera: Scolytinae) emerging from Pinus densiflora Sieb. et Zucc. (Pinaceae)

Summary An undescribed Cryptaphelenchus species was isolated from a bark beetle, Cryphalus fulvus , collected from the inner bark of a dead Japanese red pine, Pinus densiflora , in Kyoto, Japan. The nematode is described as a new species, Cryptaphelenchus fulvus n. sp., characterised by the presence of seven genital papillae in the male arranged as 1 + 2 + 2 + 2; a bursal flap-like cuticular extension surrounding the male tail, and intraspecific variation in the female tail, which ranges from broad to conical in overall shape, with the tip pointed, digitate, or rounded. Additionally, females with a broad tail possess a small papilla-like projection on the dorsal side of the tail near the tip, a unique feature of this species. Phylogenetically, the new species is closely related to Cryptaphelenchus orientalis , C. varicaudatus , and C. paravaricaudatus , but can be differentiated from these species based on molecular phylogenetics, several typological characters and morphometric values.