Standeria transvaalensis Jamieson 1968

Jamieson, Barrie G. M. & Fragoso, Carlos, 2024, A monograph of the Oligochaete family Alluroididae, Zootaxa 5529 (3), pp. 401-435 : 430-431

Standeria transvaalensis Jamieson 1968 (see Figs 16,17)

Standeria transvaalensis Jamieson 1968: 82–84 , fig. 1, 2, 4–8; Brinkhurst &Jamieson 1971: 717–718, fig. 14.1A; 14.2A–F. Length 25 mm, width 1.1–l. 4 mm, segments 82. Prostomium epilobous 1/2 although lacking a separate dorsal tongue. Form cylindrical; somewhat flattened ventrally at the clitellum. Lateral lines conspicuous, in mid bc; the posterior third of IV and a number of more posterior segments set off as a distinct annulus. Intersetal ratios in XII; dd =0.2 bc =1.7 aa; ventral pairs absent in XIII; replaced in XIV and XV on each side by 6 enlarged genital setae located within paired papillae. Lengths of 4 of 6 genital setae on the left side in XIV= 0.33–0.35 mm. Length of lateral setae from the same segment 0.19 mm. Neither type of seta with distinct node but both sigmoid with tapering extremities. Greatest widths: 15 µm for a genital seta and 10 µm for a lateral seta; ornamentation absent. Clitellum saddle–shaped; apparently extending from 1/2 XII– ca XV, 1/2 XVI, 1/2 XVII (=3 1/2, 4, 5 segments); ventral margins at ca 1/4 bc. Male pores crescentic slits on low porophores at the sites of the absent ventral setae of XIII. Each porophore continuous posteriorly with a slight tumescence which extends to approximately midway between the former and the setal zone of XIV; female pores indentations at the posterior limits of each tumescence, anterior in XIV. Ventral setal couples of XVI and XVII each on slight but distinct protuberances. These protuberances confluent medially to form feebly developed transverse pads of glandular appearance. Spermathecal pores 1 pair, conspicuous in intersegmental furrow 8/9, lateral of setal lines b with very large tumescent anterior and posterior lips each of which occupies a third of the adjacent segment. Nephropores in setal lines a very close to the setal follicles.

Septa: 4/5 the first visible, it and 12/13 slightly thickened. 5/6, 7/8, 9/10 and 11/12 relatively strongly thickened; 6/7 and 8/9 moderately thickened; 10/11 and 13/14 unthickened and very delicate, as are 14/15 and succeeding septa. Septal glands attached dorsally to anterior faces of septa as far as 9/10 and also 11/12, 12/13? Oesophagus beginning in IV, widening to form the intestine, which is at least twice as wide, in mid–XV; longer and more slender in XIII than in other segments. Dorsal and ventral blood vessels single. No subneural vessel. A pair of commissural loops winding far laterally present in XII anteriad. Nephridia open holonephridia, at least as far anteriorly as XI; lacking bladders. Proandric; large lobed testes ventral and anterior in X embedded in free morulae and abundant spermatozoa which fill the remainder of the segment. Sperm funnels large, convoluted areas of septum 10/11, seminal vesicles absent. No reproductive organs or cells in XI. On each side, overlying the external male pore on XIII is a rounded muscular atrial chamber into which discharges the tubular entally dilated atrium of the corresponding side. Its ectal portion narrowed to form a slender duct which curves ventrally and medially to join the anterolateral aspect of the atrial chamber. This ectal region obscured by a web of muscle fibres, passing from the ventral to the lateral body wall, which bind it to the latter. A second, spindle–shaped sac about the width of the atrial duct, projects from the junction of the atrial chamber with the duct and apparently represents the thickened end of the vas deferens. The walls of the atria and of the appended sacs lined by cuboidal epithelium outside which is a layer of circular muscle fibres several times as thick. The wide lumen of the atrial chamber lined by columnar epithelium outside which is a thick sheath of radial and circular muscle fibres. Glandular investment of these male terminalia absent. Ovaries in XIII. Septum 13/14 evaginated posteriorly on each side as a broad funnel continuous into XIV as a slender oviduct. Spermathecae a pair of elongated, adiverticulate pouches in IX; their scarcely narrowed ducts being almost wholly embedded in the body wall.

Distribution. South Africa: Mpumalanga Province, in the former Transvaal, (Lake Chrissie).