Tantunema indicum Ahad &amp; Ahmad, sp. nov.
Creators: name: Ahad, Sumaya
name: Ahmad, Wasim
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Nematoda
Adenophorea
Dorylaimida
Tylencholaimidae
Tantunema
Tantunema indicum

description: <i>Tantunema indicum</i> sp. nov. (Figures 5 and 6; Table 3) <i>Description</i> <i>Female.</i> Small sized nematodes, slightly curved upon fixation; body cylindrical, tapering gradually towards both the extremities. Cuticle with two distinct layers, 1 μm thick at midbody and 2.0 <i>–</i> 2.5 μm on tail. Outer cuticle smooth; inner layer finely transversely striated. Lateral chords occupying about one-third of the midbody diameter. Lateral, dorsal and ventral body pores indistinct. Lip region cap-like, offset by slight constriction, 2.4 <i>–</i> 3.0 times as wide as high or about one-third of the body diameter at neck base. Lips amalgamated; labial papillae barely raised. Amphids small, aperture a short transverseslit. Cheilostome a truncate cone. A weak post-labial thickening present. Odontostyle slender, 1.0 <i>–</i> 1.1 times the lip region diameter long, its aperture one-quarter or one-fifth of the odontostyle length. Odontophore rod-like with slight swollen base, 1.2 <i>–</i> 1.5 times the odontostyle length. Guiding ring simple, refractive, at 0.6 times lip region diameter from anterior end. Pharynx consists of a slender and weakly muscular anterior part, expanding gradually into a cylindrical basal bulb, occupying about 35 <i>–</i> 41 % of total neck length, with thick-walled lumen; lumen of the basal portion of expanded part distinctly widened and thickened. Pharyngeal gland nuclei and their orifices located as follows; DO = 74 <i>–</i> 75; DN = 78 <i>–</i> 79, S 1 N 1 = 84 <i>–</i> 85, S 1 N 2 = 86 <i>–</i> 87, S 2 N = 92 <i>–</i> 93, S 2 O = 93 <i>–</i> 94. Cardia short, conoid, about one-third of the corresponding body diameter long. Nerve ring located at 45 <i>–</i> 56 % of neck length. Genital system mono-opisthodelphic. Ovary reflexed, measuring 31 <i>–</i> 61 µm long; oocytes arranged in single row except near tip. Oviduct joining the ovary subterminally. Oviduct separated from the uterus by a narrowing but no apparent sphincter seen. Anterior genital branch completely absent. Vagina directed posteriorly; <i>pars proximalis vaginae</i> 5 <i>–</i> 6 µm long, its wall encircled by muscles; <i>pars distalis vaginae</i> short, 1 <i>–</i> 2 µm long with slightly curved walls; <i>pars refringens</i> absent. Vulva apparently a transverse slit. Prerectum 2.0 <i>–</i> 2.5 and rectum 0.7 <i>–</i> 0.8 times anal body diameter long. Tail short, hemispheroid, 0.8 <i>–</i> 1.1 times anal body diameter long. Caudal pores two on each side. <i>Male.</i> Not found. <i>Type habitat and locality</i> Soil samples collected from around the roots of forests trees, Kaziranga National park, Assam, India. <i>Type specimens</i> Holotype female on slide <i>Tantunema indicum</i> sp. nov. / 1; paratypes females on slides <i>Tantunema indicum</i> sp. nov. / 2 <i>–</i> 7; deposited with the nematode collection of the Department of Zoology, Aligarh Muslim University, India. <i>Etymology</i> The new species is named so because it is recorded from India. <i>Diagnosis and relationships</i> <i>Tantunema indicum</i> sp. nov. is characterized by having small body (length 0.32 <i>–</i> 0.45 mm); lip region cap-like, set off by slight constriction; odontostyle 6 <i>–</i> 7 µm and odontophore 8 <i>–</i> 10 µm long; pharynx with slender anterior part, which expands gradually into cylindrical basal expansion, occupying about 35 <i>–</i> 41 % of total neck length, lumen of posterior expanded part distinctly widened and thickened; female genital system mono-opisthodelphic, anterior genital branch absent; tail short, hemispheroid, 0.8 <i>–</i> 1.1 anal body diameter long. In its body size, the presence of thick-walled lumen of the posterior part of pharyngeal expansion and tail shape, the new species comes close to <i>Tantunema enigmatum Ahmad and Baniyamuddin, 2010</i>, however, it differs from it in having slightly narrow lip region (versus 6.5 <i>–</i> 7.2 µm); in the absence of circum oral sclerotization (versus circum oral sclerotization well developed); vulva slightly anterior (versus V = 46 <i>–</i> 49 %); pharyngeal expansion not constricted (versus pharyngeal expansion constricted); tail slightly longer, rounded <i>–</i> hemispheroid (versus tail 9.6 <i>–</i> 10.5 µm long, hemispheroid <i>–</i> clavate). It differs from <i>T. bothriocephalum Siddiqi, 1982 in</i> the absence of post-labial sclerotization, comparatively longer odontostyle and odontophore (versus odontostyle 4.5 <i>–</i> 6.5 µm; odontophore 6 <i>–</i> 9 µm); pharyngeal expansion gradual (versus pharyngeal expansion abrupt); basal part of lumen of pharyngeal bulb distinctly widened and thickened (versus not thickened); comparatively anterior vulva position (versus V = 45 <i>–</i> 51 %). The new species differs from <i>T. pakistanense (Timm, 1964)</i> comb. nov. in having comparatively smaller body size (versus 0.42 <i>–</i> 0.54 mm), in the shape of lip region (lip region 2.4 <i>–</i> 3.0 times as wide as high versus 1.6 <i>–</i> 2.0 times), comparatively slender odontostyle, lumen of expanded part of pharynx distinctly widened and thickened (versus not thickened) and in having shorter hemispheroid tail (versus comparatively longer rounded conoid tail).
description: Published as part of <i>Ahad, Sumaya &amp; Ahmad, Wasim, 2016, Taxonomy of the genus Tantunema Siddiqi, 1982 (Dorylaimida: Tylencholaimidae) with description of one new and two known species, pp. 1669-1685 in Journal of Natural History 50 (27)</i> on pages 10-14, DOI: 10.1080/00222933.2016.1155670, http://zenodo.org/record/269012
description: {"references": ["Ahmad W, Baniyamuddin M. 2010. Three new and a known species of Tylencholaimoidea (Nematoda: Dorylaimida) from Singapore. Zootaxa. 2505: 51 - 64.", "Siddiqi MR. 1982. Seven new genera of dorylaimid nematodes from Colombian rain forest. Syst Parasit. 4: 69 - 87.", "Timm RW. 1964. Nematodes of the Superfamily Dorylaimoidea from East Pakistan. Proc. helminth. Soc Wash. 31: 144 - 153."]}