Proandricus lovuus, Plisko, 2003

Plisko, Jadwiga Danuta, 2003, Eleven new South African earthworms (Oligochaeta: Microchaetidae) with new information on some known species, and an inventory of the microchaetids of KwaZulu-Natal, African Invertebrates 44 (2), pp. 279-325 : 302-303

Proandricus lovuus sp. n.

( Figs 12–13 )

Etymology: Named after the Lovu River on the bank of which the holotype was found.

Material examined: KwaZulu­Natal: Holotype NMSA / Olig. 00482 on the bank of Lovu River in Richmond (29º52'S: 30º16'E) area, in moist soil, 7 December 1989, JDP . Paratypes: NMSA / Olig. 03769, 6 cl and NMSA / Olig. 03690, 1 cl, Pietermaritzburg, Scottsville (29º35'S: 30º25'E) on bank of Umsindusi River near tennis court, in 1–15 cm of sandy soil, 8 January 1989, JDP . Other material: NMSA / Olig. 00802, 25 cl + 34 juv collected in close neighbourhood of paratype locality, 8 January 1989, JDP .

Description based on holotype and paratypes.

External characters

General: cylindrical along the whole body length. Colour: alcohol­preserved yellowishwhite. Dimensions: preserved holotype 74 mm long, 3 mm wide at 10, 4 mm in region of tubercula pubertatis; paratypes 55–79 mm long, 3–4 mm wide. Segment number: holotype 144, paratype 165–176. Prostomium: prolobous. Segmentation: secondary annulation present on preclitellar segments; 1 and 2 short, with no clear segmental separation, both with irregular longitudinal grooves; 3 simple, as long as 1 and 2; 4–8 with 2 ringlets, similar in size and appearance; 9 with 2 ringlets, first longer than second; 10–11 and clitellar simple; postclitellar short, simple. Setae: moderate in size, paired; first pairs on 3, subsequent pairs of 4–9 on first ringlet. Preclitellarly aa> bc, postclitellarly ab = cd. Nephridial pores: obvious, in c setal lines; first pair in intersegmental furrow 3/4. Female pores: not observed. Male pores: externally not observed; probably in 14/15 intersegmental furrow. Spermathecal pores: two in intersegmental furrows 11/12 and 12/13.

Clitellar region ( Figs 12–13 ): Clitellum: on 11,12–21,22; saddle­shaped, segmented, whitish­grey; on 12–13 ventral edges extend to d setal lines, on 14–1/n19 to dorsal border of tubercula pubertatis; on 1/n19–21 extend below cd setae; on 11 only dorsally, thin layer of clitellar tissues. Tubercula pubertatis: on 1/n14,15–1/n19 below ventral clitellar edges; oval swellings with thin grooves at their ventral borders ( Fig.13 ). Papillae: small swellings, paired, in ab setal lines on 10–22 ( Fig. 12 ).

Internal characters

Septa: 4/5 most thickened; 7/8 and 8/9 thickened moderately; other septa thin. Gizzard: large, muscular. Calciferous glands: in 9; laterally, widely separated dorsally and ventrally. Intestine: commences in 12. Typhlosole: in holotype commences abruptly as thick U­shaped in 19; terminates in 126. Dorsal blood vessel: double in 5–7, close; 8 double, separated; 9 cordiform; 10 and following simple; simple when crossing septa. Paired dorso­ventral vessels: thin tubes in 4– 8; 9–11 moniliform, not much enlarged. Nephridia: Meganephridia , paired small tufts of coiled tubules, with thin, elongated V­shaped caeca. Spermiductal funnels: proandric arrangement; one pair in 10, closely connected at septum 10/11 with vesiculae seminales. Seminal vesicles: one large pair commencing at septum 10/ 11, extending equally into 10 and 11. Spermathecae: one pair per segment; elongated ampullae, with short, thin necks; ectal parts enter body wall close to intersegmental furrows 11/12 and 12/13 respectively; posterior pair slightly larger than anterior, iridescent. Vasa deferentia : not observed, being not fully developed or deeply embedded in body wall. Ovaries: not observed. Genital glands: flat glands, in 14– 18; partially associated with internal glands of tubercula pubertatis.

Biological notes: The holotype was collected in pasture on the bank of small stream. The paratypes were found at considerable distance from the type locality, on bank of the Umsindusi River. Degradation of both areas, and water pollution were in evidence.

Discussion: Three thickened septa and spermathecal pores in 11/12 and 12/13 suggest species assignation to the belli species­group, although septum 4/5 is not thickened as much as is observed in the other species of this group. P. lovuus resembles the similarly sized setosus . Both species have spermathecae matching in shape. They differ notably in the shape and location of the seminal vesicles, commencement and extension of typhlosole. The moderate size of setae in lovuus also distinguishes it from setosus .

Distribution: The species is known only from two sites, both in Pietermaritzburg area ( Fig. 7 ).

Figures

Figs 12–13. Proandricus lovuus sp. n. 12. Holotype, dorso­lateral view with row of small papillae. 13. Paratype, enlarged lateral side with tuberculum pubertatis. [C = clitellum, T = tuberculum pubertatis, P = papilla of segment 18].

Fig. 7. The distribution of Proandricus species in KZN. 1 = adami; 2 = adriani; 3 = alatus; 4 = amphius; 5 = armstrongi; 6 = babanango; 7 = beddardi; 8 = bergvillensis; 9 = bourquini; 10 = bulwerensis; 11 = colletti; 12 = crookesi; 13 = entumeni; 14 = gracilis; 15 = hedothecus; 16 = hlatikulu; 17 = injasuti; 18 = ivari; 19 = jasoni; 20 = lovuus; 21 = marleyi; 22 = martensi; 23 = michelleae; 24 = modestus; 25 = oresbiosus; 26 = ortyi; 27 = pajori; 28 = richerti; 29 = setosus; 30 = thornvillensis.