Goffartia filicaudata ( Andrássy, 1968 ) Sudhaus & Fürst

Tahseen, Qudsia & Mustaqim, Malka, 2015, A taxonomic review of the genus Goffartia Hirschmann, 1952 (Rhabditida: Diplogastridae) with a note on the relationship of congeners, Zootaxa 4034 (1) : -

Goffartia filicaudata ( Andrássy, 1968) Sudhaus & Fürst von Lieven, 2003

( Figs. 1 B, 2A, 3B, 6)

Measurements. Table 1

Description. Adult: Body medium to large-sized. Cuticle slightly thickened, 0.4 to 0.6 µm with very fine transverse striations and without longitudinal striations. Lateral field demarcated. Lip region continuous or very slightly offset from the adjoining body, 6–7 µm wide, almost flat, rounded to truncate. Lips with fine setose labial sensilla; cephalic sensilla in females much smaller than those of males. Amphids conspicuous, located at middle or posterior level of stoma. Amphidial aperture oval in shape, about 4 µm wide, about 40–50% of the corresponding body width or about 1.0–1.5 times stoma width; amphidial pouches (foveae) funnel-shaped, amphidial canals short with inconspicuous fusus. Stoma cuticularised, about 3 times longer than wide, without any ring. Cheilostom markedly longer than gymnostom, gymnostom arched, stegostom tubular. Pro-, meso-, meta- and telostegostom forming a hollow chamber; metastegostom with a bristle-shaped, slightly arcuate tooth, directed forward. Anterior part of pharynx muscular, longer than the posterior part, about 55% of the total pharyngeal length; median bulb strongly developed; basal bulb slightly demarcated from isthmus, pyriform. Nerve ring encircling the pharynx at the middle of isthmus. Secretory-excretory pore in the middle to posterior region of pharynx or posterior to nerve ring. Body in the proximal part of pharynx 2.5–3.0 times wider than lip region. Intestine with fine granules. Rectum 1.5–1.6 times longer than anal body diameter. Tail very long, filiform, similar in both sexes, 30–37 times anal body diameters, with very fine hair-like terminal part.

Female: Reproductive system didelphic, amphidelphic; length of genital branches 5–6 times body diameter. Ovaries reflexed, long, narrow, almost equal in length; proximal oocytes having conspicuously large nuclei. Vulva largely pre-equatorial, vagina weak.

Male: Similar to female in general morphological characters except smaller body. Tail divided into an anterior conical part and an abruptly narrowing cylindrical part terminating in a whip. Spicules slender, almost falcate, proximally knobbed, distally tapering to a fine tip. Gubernaculum well developed, trough-shaped, proximally hooked, about half of spicule length. Genital papillae setose, nine pairs with two pre-cloacal and seven post-cloacal pairs with a configuration of v1, v2 / v3 d, v4, ad, (v5, v6 + v7), pd. The genital pair v1 and v2 closely spaced, subventral; v3 d slightly post cloacal, lateral; v4 subventral about anal body diameter posterior to cloaca; ad lateroventral; v5 slightly distant to closely placed v6 and v7, all subventral and a subdorsal pd. Phasmids presumably located between ad and v5. Tail divided into an anterior conical part and a suddenly narrowing filamentous part ending in a hair-like terminus.

Locality and habitat. Goffartia filicaudata was reportedly collected from the soil around the plant roots at the edge of a pond from Isangi, Tanzania ( Andrássy,1968). The species has not been reported elsewhere since then.

Salient characters. The species is characterised by cuticle with fine transverse striations but no longitudinal lines; slightly offset lip region with fine setose labial sensilla; amphids transversely oval, about 40–50% of the corresponding body width or about 1.0–1.5 times stoma width; stoma elongate having arched gymnostom and tubular stegostom, a bristle-like metastegostomal tooth; anterior part of pharynx longer than posterior part; genital branches of female gonad almost equal; males with spicules slender, almost straight; gubernaculum proximally hooked, about half of spicule length and genital papillae v5 slightly distant from closely placed v6 and v7 genital pairs.

Remarks. The gubernaculum is of a characteristic shape, about 50–60% of the spicule length, with a hooked proximal end. The gubernaculum as mentioned in the identification key of G. filicaudata (apud Singh et al., 2014) is stated to be distally recurved presumably due to oversight.

Figures

FIGURE 1. Anterior body ends. A: Goffartia africana. B: G. filicaudata. C: G. heteroceri. D: G. variabilis. E: G. praepilata. F: G. phalacra. G: Female reproductive system in Goffartia sp. (Scale bar = 10 µm).