Morphological and Molecular Characterization of a Novel Fungal-feeding Stem Nematode Ditylenchoides agaricivorus n. sp. (Tylenchida: Anguinidae) from Intercepted Samples

A new species of the genus Ditylenchoides, D. agaricivorus n. sp., collected from coconut fiber used as growing media for staghorn ferns and intercepted during import quarantine, is described and illustrated herein based on morphological and molecular studies. The new species is characterized by a body length of 728 (612–846) μm and 641 (511–720) μm in female and male, respectively, delicate stylet 8.0 (7.4–8.4) μm long, six lines in the lateral field, median bulb of esophagus well-developed, muscular with crescentic valve, post-vulval uterine sac well-developed, 36 (22–52) μm long, female tail elongate-conoid with finely rounded terminus. The results of phylogenetic analyses based on sequences of the D2D3 expansion region of 28S rRNA and ITS confirmed the close molecular relationship between D. agaricivorus n. sp., and other Ditylenchoides species such as D. africanus, D. arachis, D. destructor, D. halictus, D. myceliophagus and D. persicus. Ditylenchoides agaricivorus n. sp. was successfully reared on the Rhizoctonia solani and Agaricus biporus. However, D. agaricvorus n. sp. did not reproduce when culturing on Lentinula edodes, Pleurotus erungii, Volcariella volvacea, A. bitorquis, nor on callused carrot disks, and alfalfa seedlings.