New insights into the identity of Discolaimium dubium Das, Khan and Loof, 1969 (Dorylaimida) as derived from its morphological and molecular characterization, with the proposal of its transference to Aporcella Andrássy, 2002

Abstract

Three Iranian populations of Discolaimium dubium are studied, including their morphological and morphometric characterization, molecular analysis (LSU-rDNA) and the description of the male for the first time. For comparative purposes, this species is distinguished by its 1.10 to 1.40 mm long body, lip region offset by constriction and 8 to 10 µm wide, odontostyle 7.5 to 10.5 µm long with aperture occupying 59 to 76% of total length, neck 300 to 362 µm, pharyngeal expansion 127 to 181 µm long or 44 to 46% of the total neck length, uterus simple and 38 to 53 µm or 1.2 to 1.5 times the body diameter long, V = 52 to 58, tail conical (32-38 µm, c = 32-43, c′ = 1.6-2.0) with rounded tip and a hyaline portion occupying 14 to 15% of tail length, spicules 30 to 32 µm long, and two or three widely space ventromedian supplements with hiatus. Both morphological and molecular data support its belonging to the genus Aporcella, whose monophyly is confirmed and to which the species is formally transferred as A. dubia (Das et al., 1969) comb. n.

Description of Aporcella coffeae sp. nov. (Nematoda: Dorylaimida: Aporcelaimidae), Associated with Coffee Plantations in Central Highland of Vietnam

“…Remarks . As mentioned earlier, the new species forms a rather homogeneous group with a few Aporcella representatives, characterized by their large general size (body much exceeding 3.0 mm long; Table 2), which sharply distinguishes them from the remaining 18 species of the genus, with medium-sized bodies ranging from 1.23 to 3.08 mm (see compilations by Álvarez-Ortega et al 2013, Vazifeh et al 2021). Morphologically, these species share a similar lip region nature (offset by deep constriction), large pharyngeal expansion (more than one-half of the total neck length), nearly identical tail shape, and lack male.…”

“…Thus, Álvarez-Ortega et al (2013) presented a new concept, including thirteen species. More recently, Vazifeh et al (2021) updated its diagnosis, listed a total of 18 valid species, and provided a key for their identification. Later, two more species were added to the catalogue, either new (Rashidifard et al 2021) or transferred (Vazifeh et al 2021).…”