Description of Geocenamus vietnamensis sp. n. (Nematoda : Merliniidae) from Vietnam

A new species of the genus Geocenamus was isolated from soil and root samples from the rhizosphere of Casuarina equisetifolia (Casuarinaceae) in Quang Nam province, Vietnam. This species is characterized by a round-to-hexagonal labial disc, the presence of a labial region, which is continuous or slightly offset from the body with six sectors, lateral sectors of first labial annulus being smaller than the submedian sectors, the presence of six to seven labial annules; the absence of deirids; stylet length 24 to 28 mu m long, body length 776 to 979 mu m long; lateral field with six to eight lateral lines, without areolation at mid-body and with areolation in outer bands at the tail region and a pointed tail terminus. Geocenamus vietnamensis n. sp. most closely resembles G. boghiae in having a non-sclerotized head framework and lacking a bursa in the males. It can be clearly distinguished from all other species of the genus Geocenamus by these characteristics. The combination of morphology, morphometric features, and phylogenetic trees, based on D2-D3 of 28S and ITS rDNA sequences, showed that this new species can be clearly separated from all other sequenced species. This record is the first for Geocenamus in Vietnam

Morphological and molecular characteristics of Pratylenchus haiduongensis sp. n., a new species of root-lesion nematodes associated with carrot in Vietnam

Pratylenchus haiduongensis sp. n. is described as associated with carrot (Daucus carota subsp. sativus (Hoffm.) Schubl. & G. Martens) in Hai Duong Province, Vietnam. P. haiduongensis sp. n. is characterized by the lip region with three annuli and slightly separated from the body. Stylet knobs are rounded (never indented anteriorly). The lateral field includes four incisures, bearing areolation at the pharynx region and tail region and occasionally appears in the vulval region. Sometimes the appearances of oblique broken striaes divide the lateral field into five or six incisures. The ovary is distinct with one row of oocytes. Spermatheca is oval in shape with round central cavity, without sperm or reduced in some specimens. The postvuval uterine sac is long surpassing the vulva body diameter by 2 to 2.5 times (PUS = 31 to 65 mm). High vulva position with V = 66 to 75%. The tail shape can be subhemispherical with a smooth, slightly indented, broadly smooth, or cleft terminus observed in some specimens. The matrix code of P. haiduongensis sp. n. is: A2, B1, C4, D(1,3), E1, F(5,6), G(1,2), H(1,4); I(1,2,3,4), J1, K(1,2) according to Castillo and Vovlas (2007). The LSU-D2D3 segment and the ITS-rDNA region of this species were amplified and sequenced. The morphological characters and molecular phylogenetic analyses confirmed that this is a new species of the genus Pratylenchus in Vietnam

A new root-knot nematode <em>Meloidogyne spartelensis</em> n. sp (Nematoda: Meloidogynidae) in Northern Morocco

International audienceLow density of an unknown root-knot nematode was found on wild olive soils at Cape Spartel near Tanger city in northern Morocco. Morphometry, esterase and malate dehydrogenase electrophoretic phenotypes, as well as ribosomal DNA (rDNA) and mitochondrial DNA (mtDNA) sequences demonstrated that this nematode species differs clearly from other previously described root-knot nematodes. The species is herein described, illustrated and named as Meloidogyne spartelensis n. sp. This new root-knot nematode can be morphologically distinguished from other Meloidogyne spp. by: (i) roundish perineal pattern, dorsal arch low, with fine, sinuous cuticle striae, lateral field faintly visible; (ii) female excretory pore posterior to stylet knobs, EP/ST ratio 1.4-2.0; (iii) second-stage juveniles with hemizonid located 1 to 2 annuli anterior to excretory pore and long, sub-digitate tail; and (iv) males with lateral field composed of four incisures, with areolated outer bands. Phylogenetic trees based on 18S, ITS1-5.8S-ITS2, D2-D3 of 28S rDNA, and partial coxII-16S rRNA and coxI gene of mtDNA showed that M. spartelensis n. sp. belongs to an undescribed root-knot nematode lineage that is clearly separated from other species with resemblance in morphology, such as M. dunensis, M. kralli, and M. sewelli