Parachilota minimus Zicsi & Pajor, 1992

Plisko, J. D., 2008, New South African Acanthodrilinae earthworm species, with new data for some earlier known members of the genus Parachilota (Oligochaeta: Acanthodrilidae), African Invertebrates 49 (2), pp. 21-21 : 32-33

Parachilota minimus Zicsi & Pajor, 1992

Fig. 12

Parachilota minimus: Zicsi & Pajor 1992: 133 .

Material studied: KwaZulu-Natal: NMSA / Olig. 03817, 1 cl, Drakensberg, Cathedral Peak (28°45'S: 29°05'E), at ca 1500 m, 13.xii.1991, A. Zicsi & I. Pajor; NMSA / Olig. 02186, 1 cl, & NMSA / Olig. 2191, 3 cl, Ngele Forest (30°35'S: 29°41'E), moist litter & first 20 cm black, moist soil, 23–24.xi.1995, JDP & BRS .

Distribution: The species was reported by Zicsi and Pajor (1992) from the Cathedral Peak area, including the Ndumeni Forest, Doreen Falls, and the vicinity of the hotel buildings, all in the eastern Drakensberg Mountains. Present records extend the known range to Drakensberg foothills in southern KZN.

Comments: The studied material matches the description of the species ( Zicsi & Pajor 1992). The species is characterized by a bilobate spermathecal diverticulum, clearly divided by a narrow furrow ( Fig. 12 ). The ornamentation of the penial setae is similar to that shown in the type description, although it was observed only under 500× magnification.

MULTILOBATE species-group

Parachilota uysae sp. n.

Fig. 13

Etymology: Named after Mrs C. Uys, who collected the type series.

Diagnosis: Spermathecal pores in intersegmental furrows 7/8 and 8/9. Clitellum ringshaped on 13–17. Prostatic pores not approximate towards the mid-ventral line, in 17 and 19. Male pores in 18. Gizzard in 5, moderately developed. Commencement of intestine in 16. Last pair of lateral hearts in 12. Spermathecal multilobate diverticulum with three lobes attached to spermathecal duct at its basal part.

Description:

External features: Body cylindrical. Alcohol-preserved over three years: on preclitellar segments dorsally violet reddish, postclitellarly and ventrally yellowish grey. Dimensions: Holotype 45× 3 mm; paratypes 30× 2 mm. Segment number: Holotype 85, paratype 112. Prostomium: Tanylobous, tong wide with conspicuous sutures. Setae: Widely paired; postclitellarly aa <bc; ab <cd; bc> cd. Dorsal pores: Not observed. Nephridial pores: Not observed. Spermathecal pores: Paired, in 7/8 and 8/9, in front of b setae. Female pores: In 14, between aa setae. Clitellum: On 13–17, ring-shaped; encircling segments equally. Prostatic pores: Paired, not approximated towards midventral line, in 17 and 19, between ab setae; each pore with small encircling swelling. Male pores: In 18, small openings close to b setae. Seminal grooves: Curved. Papillae: Not observed.

Internal characters: Salivary glands: Do not extend beyond 4/5. Gizzard: In 5, moderate in size. Septa: Anterior thin, not muscular; 8/9–13/14 slightly thickened. Intestine: Preceded by thin folds in 15 commences abruptly in 16. Lateral hearts: Last pair in 12. Nephridia: Holoic ; elongated coiled loops without terminal vesicles. Ovaries: Not observed. Testes and male funnels: Ventrally in 10; male funnels free, iridescent. Vasa deferentia: Not observed. Seminal vesicles: 2 pairs; in 9 and 11; anterior pair commencing at 9/10, smaller than posterior; posterior commencing ventrolaterally at 10/11 extends dorsolaterally; both irregularly shaped. Spermathecae ( Fig. 13 ): Paired, in 8 and 9. Ampulla elongated-ovoid, smooth, empty; spermathecal duct, wide, extended. Diverticulum at basal part of duct with three chambered lobes: one middle lobe and two lateral lobes rounded, iridescent. Ectal parts of spermathecal ducts enter body wall near intersegmental furrows 7/8 and 8/9. Prostates: 2 pairs; in 17 and 19. Duct short, thin, confined to ventral part of one segment. Prostatic gland multi-looped extending dorsolaterally. Penial setae: Setae of 17 and 19 transferred into similar penial setae, although not fully mature. Penial setal retractor muscles: Commence at intersection of 17/18 and 18/19.

Comparison: The species has multilobate diverticula, similar to P. warreni (Michaelsen, 1913) . The two species differ in the shape of the spermathecae and in the starting position of the intestine, which is in segment 16 in P. uysae and segment 17 in P. warreni .

Holotype: KwaZulu-Natal: NMSA / Olig.03916 , uKhahlamba-Drakensberg Park World Heritage, Injasuthi (29°06'35.4"S: 29°26'20.7"E), van Henningens Pass Forest , at 1604 m, down steep slope, 20 m from path, near muddy, rocky patch in leaf litter, after rain, 21.iii.2004, C. Uys.

Paratypes: NMSA / Olig.03917 , 1 juv collected with holotype ; NMSA / Olig.03918 , 1 semi-mature, uKhahlamba-Drakensberg Park World Heritage , Injasuthi (29°07'10.2"S: 29°26'10.9"E), yellow-wood Podocarpus forest, at 1466 m, in big old knarled yellow-wood log. All collected by C. Uys.

Biological notes and distribution: The presence of sperm in male funnels and spermathecal diverticula indicates sexual activity during the summer, extending to early autumn. This species was collected during a study of invertebrate diversity in Afrotemperate forests of the Drakensberg Mountains undertaken by C. Uys. The study area falls under the protection of Ezemvelo KZN Wildlife, although beforehand it was variably exploited by people ( Pooley & Player 1995). Human impact on the environment has had many serious implications for the survival of the endemic fauna. Uys (2006) evaluated patches of indigenous forests as refuges for many indigenous invertebrates.Although only three specimens of P. uysae were found in the investigated protected area, in the close neighbourhood the acanthodriline Udeina adriani Plisko, 2004 , the microchaetid Proandricus injasuti Plisko, 2002 and other species: Dichogaster sp. of Benhamiinae, megascolecid Amynthas sp. , and exotic lumbricids Apporrectodea rosea (Savigny, 1826) , Dendrodrilus rubidus (Savigny, 1826) were also found, confirming the value of protected indigenous areas. P. uysae is known only from its type locality in the foothills of the Drakensberg Mountains in central KZN.

Figures

Figs 11, 12. Spermathecae of Parachilota species with bilobate diverticulum: (11) P. karkloofi Zicsi, 1998, holotype, 400×; (12) P. minimus Zicsi & Pajor, 1992, 500×. Abbreviations: A – ampulla, BDv – bilobate diverticulum.

Figs 13, 14. Spermathecae of Parachilota species with multilobate diverticulum, 500×: (13) P. uysae sp. n., holotype; (14) P. warreni (Michaelsen, 1913), spermathecae from ventral side of body. Abbreviations:A – ampulla, D – spermathecal duct, MDv – multilobate diverticulum, MDvl – left part of multilobate diverticulum of anterior spermathecae, MDvm – medial part of multilobate diverticulum of posterior spermathecae, MDvr – right part of multilobate diverticulum of anterior spermatheca.