Proandricus martensi, Plisko, 2002

Plisko, Jadwiga Danuta, 2002, Nine new earthworm species of Proandricus Plisko, 1992 from South Africa and Lesotho (Oligochaeta: Microchaetidae), African Invertebrates 43, pp. 183-204 : 194-196

Proandricus martensi sp. n.

( Fig. 7 )

Etymology: Named for Dr K. Martens from the Royal Belgian Institute of Natural Science, who assisted Dr M. Hamer of the School of Botany & Zoology, University of Natal, Pietermaritzburg, in collecting the type specimen.

Material examined: SOUTH AFRICA: KwaZulu-Natal: Holotype NMSA /Olig.03525 clitellate, Drakensberg Gardens, Mzimkulwane area (29º42'S: 29º19'E) on surface of path during rainy day, 16 February 1998, M. Hamer and K. Martens leg. Paratypes: NMSA /Olig.03526 3 clitellate and 3 juvenile, Underberg area (29º46'S: 29º32'E), Tegwan Farm, from pasture at ca. 15 cm depth, 23 November 2001, A. Sanders leg.

Description based on holotype and paratypes.

External characters:

General: Body cylindrical. Colour: Alcohol-preserved whitish-grey. Dimensions: Preserved holotype 115 mm long, 4 mm wide at segment 10, 6 mm at tubercula pubertatis; paratypes 92+ – 145 mm long, 7 mm wide at segment 10, 8 mm at tubercula pubertatis. Segment number: Holotype 326, paratypes (abscides197+) and 300. Prostomium: Prolobous, moderate. Segmentation: Secondary annulation present on preclitellar segments; 1 and 2 with longitudinal grooves; 3 simple, as long as first ringlet of segment 4; 4–8 with two simple ringlets, similar in size and appearance; 9 with two ringlets, second shorter than first; segments 10–12 and postclitellar simple. Setae: Small, closely paired; first pairs of ab on segment 3; on annulated segments on first ringlet; postclitellarly ab nearly equal to cd. Nephridial pores: Conspicuous, near cd setal lines; first pair in intersegmental furrow 3/4. Female pores: In 14, slightly below ab setae. Male pores: Externally not evident; probably in segment 18, or in intersegmental furrow 17/18 or 18/19, this position suggested by vasa deferentia entering body wall in segment 18. Spermathecal pores: In intersegmental furrows 11/12 and 12/13.

Clitellar region ( Fig.7 ): Clitellum: Saddle-shaped, segmented; on holotype on 13–23 with clitellar tissues on segment 13 much thinner than on following clitellar segments; on paratypes all clitellar segments 13–23 evenly covered. On segments 13–16 and 20– 23 clitellar ventral edges extended nearly to ab setal lines; on 17–19 terminating at edges of tubercula pubertatis. Tubercula pubertatis: On segments 17–19, close to ab setae, a pair of narrow, swollen, segmented ridges extending longitudinally; segmented surfaces extending between lateral borders of ridges and clitellar borders becoming vertically stretched, curved and at joints with clitellum they modify into longitudinal cavities. On paratypes a ratio of the curved segmental surfaces converted into cavities varies; it could be due to different states of maturity. Papillae: On 10 and 11 paired, small swellings around ab setae; on 12 and 24 moderate in size, swollen tubercles containing ab setae; all associated with genital glands.

Internal characters:

Septa: 4/5 5/6 6/7 thin, not thickened; 7/8 and 8/9 thickened, muscular, similar in size and appearance; other septa thin, firm. Gizzard: In 7, muscular, posteriorly soft. Calciferous glands: In 9, globular, connected with oesophagus vertically; distantly separated dorsally and ventrally. Intestine: Commences in 13. Typhlosole: Commences in 13 as narrow V-shaped tube, gradually enlarging, and in segment 20 becoming large and U-shaped; terminates in holotype in 133, in paratypes 128–147. Dorsal blood vessel: In 4–7 double only in posterior parts of segments, not separated; in 8 double, separated; in 9 double, cordiform; single when crossing septa, in 10 and in the following segments. Paired dorsoventral vessels: Thin vessels in 5–8, enlarged, moniliform in 9–11. Nephridia: Meganephridia ; coiled loops and V-shaped, short caeca.

Reproductive organs: Spermiductal funnels: Proandric arrangement (in segment 10); one pair of large funnels enclosed in common sac; both funnels closely connected with seminal sacs at posterior part of segment 10; iridescence confirms presence of sperm. Vasa deferentia: Single ducts commence from spermiductal funnels at their lateral sides and run backward medially at each side of body to segment 18, where they enter body wall; it is difficult to determine exact entry to male pores because these are not marked externally; probably they are in intersegmental furrow 18/19 or 17/18. Seminal vesicles: One pair of moderate vesicles, anteriorly connected with spermiductal funnels at septum 10/11, and confined to segment 11. Spermathecae: Two pairs per segment near septa 11/12 and 12/13; tiny, irregularly shaped thecae; anterior pair much smaller than posterior. Ovaries: Not observed, covered by body wall tissue. Genital glands: In segments 12 and 24; paired, moderate in size and similar in appearance, two-folded, elongated glands, associated with papillae.

Biological notes: Collected on outskirts of Drakensberg escarpment, in Afromontane forest with alien plantations of wattle and pine trees. Holotype associated with the new species michelleae , described below. Paratypes found in Drakensberg foothills were associated with the introduced species Octolasion lacteum (Oerley, 1885), which occurs commonly in the neighbouring pastures and grasslands.

Discussion: P. martensi can be assigned to the P. colletti species-group, having only septa 7/8 and 8/9 thickened and spermathecal pores in two intersegmental furrows 11/ 12 and 12/13. Similar to my new species michelleae , but both species differ distinctly in the shape of the clitellum and tubercula pubertatis.

Figures

Figs 6–7. Proandricus species. Clitellar region, ventral view. 6. P. injasuti sp. n. 7. P. martensi sp. n. [C = clitellum; T = tuberculum pubertatis.]