Turbiditylenchus corticeus n. gen., n. sp. (Rhabditida: Anguinidae) from the bark of Eucalyptus macrorhyncha from the Australian Capital Territory

Summary A new genus and species of the Anguinidae, Turbiditylenchus corticeus n. gen., n. sp., was isolated from the bark of Eucalyptus macrorhyncha from southeastern Australia. Turbiditylenchus corticeus is readily differentiated from all recognised anguinid genera and is characterised primarily by a slender body, lateral field with six incisures, an anteriorly flattened lip region continuous with the body, delicate stylet 7.9-9.9 μ m long, muscular median bulb containing a strongly refractive valve, post-vulval uterine sac 1.87-4.4 times vulval body diam., conical tail with pointed tip, and males with leptoderan bursa and spicules 20.5-25.8 μ m in length. The phylogenetic relationships of the new species with other anguinid lineages were reconstructed using sequences of the small subunit ribosomal RNA (18S rRNA), the internal transcribed spacer region (ITS; comprising ITS1-5.8S-ITS2) and partial large subunit ribosomal RNA (28S rRNA D2-D3) genes based on Bayesian inference and maximum likelihood analyses. These analyses demonstrate the new species represents a lineage distinct from all other anguinids. Based on phylogenetic results we also transfer Ditylenchus parvicauda Gu, Ma, Castillo & Munawar, 2024 and Ditylenchus gracicauda Gu, Ma, Castillo & Munawar, 2024 to Ditylenchoides Subbotin & Ryss, 2024 as Ditylenchoides parvicauda n. comb. and Ditylenchoides gracicauda n. comb.