Descriptions of Trichodorus lownsberyi sp. n., Nanidorus minor (Colbran, 1956) Siddiqi, 1974 (Nematoda: Trichodoridae) and Longidorus quercus sp. n. (Nematoda: Longidoridae) from Mexico

Abstract

Summary A new species of stubby root nematode, Trichodorus lownsberyi sp. n., collected from soil around Buxus sempervirens at Montecillo Campus, Colegio de Postgraduados, Mexico, is described and illustrated. Trichodorus lownsberyi sp. n. is characterised by the abundant males with a characteristic spicule shape, the narrower part about mid-blade having visible bristles in most specimens, and the presence and position of the three ventromedian cervical papillae, which are all anterior to the secretory-excretory pore. Females possess a rhomboid-shaped vagina and oval to rounded triangular vaginal sclerotised pieces with a pore-like vulva. The phylogenetic relationships of T. lownsberyi sp. n. with related species were constructed using the ITS2 rRNA and the D2-D3 expansion segments of 28S rRNA gene sequences. Trichodorus lownsberyi sp. n. was a sister species to T. viruliferus in the phylogenetic trees. A Mexican population of Nanidorus minor from a peach orchard is also described and illustrated. The new needle nematode, Longidorus quercus sp. n., was recovered from soil around roots of oak, Quercus crassipes, from Cerro Jusda ‘El Diablo’ in Mexico State. Longidorus quercus sp. n. females are characterised by the C-shaped posterior end of the body after fixation, L = 4.9 (3.9-5.6) mm, a = 71 (60.8-93.2), lip region rounded, sometimes slightly flattened, marked by depression, odontostylet 170 (144-206) μm long, hemispherical to bluntly conoid tail and no males. The new species was characterised using the D2-D3 of 28S rRNA and COI gene sequences. The phylogenetic relationships of L. quercus sp. n. with other Longidorus species were reconstructed using the D2-D3 of 28S rRNA gene sequences.