Morpho-Molecular and Ultrastructural Characterization of Discocriconemella Parasinensis n. Sp. from Zhejiang Province, China

J Nematol. 2022 May 18;54(1):20220011. doi: 10.2478/jofnem-2022-0011. eCollection 2022 Feb.

Abstract

During a recent inventory survey of the nematofauna of tea plantation at Zhejiang Province, China, Discocriconemella parasinensis n. sp. was detected in the rhizosphere of Camellia sinensis. The new species can be characterized by having the uninterrupted rounded labial disc, en face view showing rectangular-rounded labial plate without submedian lobes, R = 82.6 (80-86), Rex = 22 (21-23), stylet length of 68.3 (59-76) μm, excretory pore located 1-2 annuli posterior to the esophageal bulb, vulva open, postvulval body elongated conoid, and tail conoid with bilobed terminus. Morphologically, the species shares the same lip-type with D. discolabia, D. mauritiensis, D. mineira, D. perseae, and D. sinensis. Phylogenetic relationships of the new species based on D2-D3 expansion segments of 28S, ITS, and 18S rRNA genes revealed that D. parasinensis n. sp. formed a separated clade from other criconematid species, thereby supporting its status as a new species of the genus. The new species showed close phylogenetic relationships with Criconemoides geraerti.

Keywords: Camellia sinensis; DNA sequencing; morphology; morphometrics; nematode; new record; phylogeny; species.