Seinura caverna n. sp. (Tylenchomorpha: Aphelenchoididae), an androdioecious species isolated from bat guano in a calcareous cave

Summary A new species of a predator aphelenchoidid,Seinura cavernan. sp., is described and illustrated. The new species was isolated from bat guano collected from a calcareous cave in Japan. The new species is characterised by its three-lined lateral field, secretory-excretory pore at the level of the posterior two-thirds of the metacorpus, a long post-uterine sac, hermaphrodite tail shape elongate conoid with a filiform tip, and an androdioecious reproductive mode. The new species is typologically and biologically close toS. steineri, but is distinguished by its longer post-uterine sac, slightly longer stylet and slightly larger median bulb. The comparisons with other morphologically similar species,i.e.,S. chertkovi,S. tenuicaudataandS. steineri, are discussed. A molecular phylogenetic analysis based on two small and large subunit ribosomal RNA genes revealed that the new species is located at the basal position of clade 3 of the Aphelenchoididae, clearly separate fromS. demani, its congener with unclear rectum and anus, which is located at the derived position, suggesting that further generic revision is necessary for the genus.Aphelenchoides liin. comb. (=Seinura lii) is proposed.