Proandricus adami, 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 : 295-297

Proandricus adami sp. n.

( Fig. 8 )

Etymology: Named for Adam Shuttleworth in recognition of his interest in earthworms.

Material examined: KwaZulu­Natal: Holotype NMSA / Olig. 02530 Drakensberg, Royal Natal National Park , on the bank of Devil’s Hoek River (28º42'S: 28º54'E), grassland, among roots, 4 December 1996, JDP , TL. Paratypes: NMSA / Olig. 02531, 6 juv, collected with holotype; NMSA / Olig. 00918, 1 cl, and NMSA / Olig. 00919, 2 abscised cl + 8 juv, collected at Drakensberg foothills, Little Berg [south of the type locality] 2 March 1989, JDP, BRS .

Description based on holotype and paratypes.

External characters:

General: body cylindrical. Colour: in life and alcohol­preserved not pigmented, whitishgrey. Dimensions: preserved and slightly contracted holotype 60 mm long, 5 mm wide at 10, 6 mm at tubercula pubertatis. Segment number: holotype 92; paratype 103. Prostomium: prolobous, small, separated from first segment. Segmentation: secondary annulation present on preclitellar segments: 1 and 2 simple, with irregular longitudinal grooves; 3 simple; 4–8 with two simple ringlets similar in size and appearance; 9 with two ringlets, second shorter than first; 10, clitellar and postclitellar simple. Setae: moderate, closely paired; first pairs on 3; preclitellarly in regular rows, posteriorly selected pairs of ab sporadically shifted into inter­setal space between bc; on 28 ab = cd, aa> bc. Nephridial pores: obvious, in ab setal lines; first pair in 2/3. Female pores: paired, in 14, slightly below cd setae, deeply in clitellar tissues. Male pores: in 17, in tubercula pubertatis area, small, simple openings. Spermathecal pores: externally not observed; however, during dissection it was noticed that ectal parts of first spermathecal pair enter intersegmental furrow 9/10; ectal parts of second pair located in segment 10 enter into intersegmental furrow 10/11.

Clitellar region ( Fig. 8 ): Clitellum: segmented, white, on 11,12–20,21; anteriorly clitellar tissues extending dorsally on part of 11; posterior border at intersegmental furrow 20/21 or 21/22; on some paratypes extending fully on 21; ventrally partially covering segments 12–15. Tubercula pubertatis: elongated oval strips, not covered by clitellar tissues, on 16–20, between cd–ab setae, separated from clitellar tissues. Papillae: little swellings, paired or single, on 10–13, 22, 23, around ab setae.

Internal characters:

Septa: 4/5 thickened, muscular; 5/6 and 6/7 not thickened, thin; 7/8 and 8/9 thickened, muscular; other septa thin, firm. Gizzard: globular, muscular, in 7. Calciferous glands: in 9, laterally; moderate, globular, distinctly separated dorsally and ventrally. Intestine: commencing in 13, developing into folded tube in following segments; in 21–27 dorsally covered by irregularly twisted paired folds. Typhlosole: commences in 21 or 22, terminates in holotype in 53. Dorsal blood vessel: double, close to each other in 5 and 7; slightly separated in 6, widely in 8; 9 enlarged, double, cordiform; 10 and following segments enlarged, simple; crossing septa simple. Paired dorsoventral vessels: 5–8 thin vessels, 9– 11 enlarged, moniliform. Nephridia: Meganephridia ; thin, elongated coiled loops with extended elongated caeca. Spermiductal funnels: proandric arrangement; one pair of large, iridescent funnels in 10, closely connected posteriorly with seminal sacs. Vasa deferentia : single, anteriorly thick ducts, commencing laterally in 10, extend through 11 and run over flat genital glands of segments 12–14, where become embedded in body wall. Ectal parts were not observed. Seminal vesicles: one pair of very large, composite sacs, irregular in shapes, commencing at septum 10/11 extending into 11 and pushing neighboring septum 11/12 expand into 12. Both sacs composed of variable in shape and size granulated lobes, communicating with base at 10/11, closely connected with spermiductal funnels. Spermathecae: in 9 and 10, one at each side; both pairs iridescent, with sperm. Anterior spermathecae narrow, club­shaped, much smaller than posteriors, with ectal parts entering body wall at intersegmental furrow 9/10. Posterior spermathecae very large, oval, with long curved ectal ducts entering intersegmental furrow 10/11. Ovaries: not observed. Genital glands: small, flat, twice­ or three­folded glands, in some of segments 9–13.

Biological notes: The species was collected in the central Drakensberg mountains, in an area protected by KZN Wildlife, in indigenous grassland slope, and in river­bank beyond the boundaries of the park. Mature and juvenile specimens were collected in both sites during summer. Iridescence observed in spermathecae confirm species sexual reproduction.

Discussion: The location of spermathecae in segments 9 and 10 is diagnostic for the lesothoensis species­group. The species is similar to amphius described below. The shape and position of clitellum and tubercula pubertatis resemble those of amphius . The typhlosole and intestine folds are also similarly located. The species differ in the postclitellar arrangement of setae and location of anterior pair of spermathecal pores. In adami pores are in the intersegmental furrow 9/10, and their activity is confirmed by the presence of sperm in the anterior spermathecae. In amphius the spermathecae are empty with their ectal parts entering the intra­segmental body wall in segment 9, a condition presently known only in amphius and sani .

Distribution: Known from the Drakensberg mountain range in western KZN ( Fig. 7 ).

Figures

Fig. 8. Proandricus adami sp. n., holotype, ventral view with clitellar tissues and tubercula pubertatis. [C = clitellum, T = tuberculum pubertatis].

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.