Aphelenchoides tenuis n. sp. (Tylenchina: Aphelenchoididae) found in loblolly pine logs imported from the USA

Abstract

Aphelenchoides tenuis n. sp. found in loblolly pine (Pinus taeda L.) logs imported from the USA, is described. It is characterised by a very slim body (a = 56.8 (45.8-67.2) and 49.1 (42.2-54.2) in males and females, respectively), three incisures in the lateral field, short stylet (9-12 μm), the excretory pore located at the level of nerve ring, the vagina is not sclerotised, the vulva has slightly protruding lips and lacks a flap and the post-uterine sac is well developed, forming ca 36.2 (28.4-48.2)% of the vulva to anus distance. The spicules are smoothly arcuate, the apex and rostrum are rounded and well developed, and the dorsal limb is 23.3 (21.1-25.5) μm long, without a hook-like structure at the distal tip. The male tail bears three pairs (2 + 2 + 2) of caudal papillae. The tail of both sexes is sub-cylindrical, the terminus bearing a bluntly pointed mucron with tiny nodular protuberances. The new species belongs to the Group 2 category of Aphelenchoides species sensu Shahina and is defined as A2-B1/2-C1-D1/2-E2-F2/3 according to the categorisation codes of OEPP/EPPO. Phylogenetic analysis based on 18S and 28S D2-D3 of rDNA, along with ITS and mtCOI, confirmed its status as a new species.