Goffartia variabilis (Micoletzky, 1922) Hirschmann 1952

• Main Authors: Tahseen, Qudsia, Mustaqim, Malka
• Format: Text
• Language: unknown
• Published: Zenodo 2015
• Subjects: Biodiversity; Taxonomy; Animalia; Nematoda; Secernentea; Diplogasterida; Diplogasteridae; Goffartia; Goffartia variabilis; Arctic; Taymyr; Arctic biodiversity
• Online Access: https://dx.doi.org/10.5281/zenodo.5684503; https://zenodo.org/record/5684503

Goffartia variabilis (Micoletzky, 1922) Hirschmann, 1952 (Figs. 1 D, 2 D, 3 D, 6) = Diplogasteroides variabilis Micoletzky, 1922 Measurements. Table 1 Description. Adults : Medium- to large-sized nematodes, between 0.8–1.2 mm in length. Cuticle with moderate transverse annulations and longitudinal striations. Lateral field with four incisures. Lip region rounded to slightly truncate, labial sensilla small, slightly raised. Amphidial apertures almost rectangular in outline, deeply carved into cuticle, double the width of buccal cavity, about one-third of the corresponding body width from anterior end. Stoma barrel-shaped, rarely longer than lip width, with weakly cuticularised cheilostom with walls straight or slightly diverging posteriorly; gymnostom and stegostom cuticularised giving a fusiform shape to the stoma. Pharyngeal corpus weakly developed, anterior part shorter than posterior part of pharynx, median bulb small with less cuticularised valve plates, isthmus narrow, leading to an oval basal bulb. Excretory pore visible, at the level of basal bulb. Tail long filiform with whip-like posterior part. Female: Reproductive system didelphic, amphidelphic, both genital branches almost equal; vulva preequatorial. Male : Similar to female in other morphological characters. Tail divided into an anterior conical part and an abruptly narrowing cylindrical part terminating in a whip. Spicules slender, 21–23 µm, about as long as cloacal body diameter, gubernaculum trough-shaped with blunt proximal end, about half of spicule length. Nine pairs of genital papillae present with 2 precloacal and 7 postcloacal pairs in the configuration: v 1, v 2 / v 3 d, v 4, ad, (v 5 + v 6, v 7), pd . The precloacal pairs v 1 and v 2 spaced and subventrally placed; v 3 d slightly postcloacal, lateral; v 4 subventral about a spicule length posterior to cloacal lip; ad lateral almost equidistant from v 4 and v 5 subventrally placed v 5 and v 6 closely spaced and distant from v 7 pd pair placed subdorsally. Locality and habitat. Goffartia variabilis is an inhabitant of freshwater reservoirs, although in wet soil it is reported to be phoretically associated with the Carabid beetle, Elaphrus riparius Linnaeus, 1758 and usually settles in the inter-segmental folds of the host’s abdomen (Steffan 1967). The species is widespread in Europe, Lake Baikal and Lake Taymyr in the territory of Russia (Holovachov 2014) and also reported from Italy, Poland, Denmark and Egypt (Zullini 1982). Salient characters. Cuticle striated transversely and longitudinally; lip region rounded to truncate with labial sensilla slightly raised; amphidial apertures about one-third of corresponding body width or two times stoma width; stoma barrel-shaped, rarely longer than lip width, with gymnostom and stegostom giving a fusiform appearance; pharyngeal corpus and median bulb weakly developed; anterior part of pharynx shorter than posterior part; both genital branches of female gonad almost equal; males with cephalated, slender spicules; gubernaculum troughshaped with blunt proximal end, about half of spicule length and genital papillae v 5 and v 6 closely placed and slightly distant from v 7 . : Published as part of Tahseen, Qudsia & Mustaqim, Malka, 2015, A taxonomic review of the genus Goffartia Hirschmann, 1952 (Rhabditida: Diplogastridae) with a note on the relationship of congeners in Zootaxa 4034 (1) , DOI: 10.11646/zootaxa.4034.1.3, http://zenodo.org/record/240726 : {"references": ["Micoletzky, H. (1922) Die Freilebenden Erd-Nematoden. Archiv fur Naturgeschichte, 87 A (1921), 1 - 650.", "Hirschmann, H. (1952) Die Nematoden der Wassergrenze mittelfrankischer Gewasser. Zoologische Jahrbucher (Systematik), 81, 313 - 407.", "Linnaeus, C. (1758) Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata. Savius, Holmiae, 4 + 824 pp.", "Steffan, A. W. (1967) Ectosymbiosis in aquatic insects. In: Henry, S. M. (Ed.), Symbiosis: Associations of Invertebrates, Birds, Ruminants and Other Biota. Academic Press Inc., New York, pp. 207 - 268.", "Holovachov, O. (2014) Nematodes from terrestrial and freshwater habitats in the Arctic. Biodiversity Data Journal, 2, e 1165. http: // dx. doi. org / 10.3897 / BDJ. 2. e 1165", "Zullini, A. (1982) Nematodi (Nematoda). Guide per il riconoscimento delle species animali delle acque intrene Italiane, 17, 1 - 117. [Verona, Italia]."]}