Wahoscolex michaelseni, Julka, J. M., Blanchart, Eric & Chapuis-Lardy, Lydie, 2004

Julka, J. M., Blanchart, Eric & Chapuis-Lardy, Lydie, 2004, New genera and new species of earthworms (Oligochaeta: Octochaetidae) from Western Ghats, South India, Zootaxa 486, pp. 1-27 : 23-26

Wahoscolex michaelseni sp. nov.

Type material: INDIA: Karnataka: holotype ( HAZFS /ZSI An810), clitellate, paratypes ( HAZFS /ZSI An811), 4 aclitellate, 6 clitellate, near Herbettu [13°54'N 74°46'E], 680– 750m, pasture, forest, October 1992 (E. Blanchart).

Additional material: INDIA: Karnataka: coll. E. Blanchart: 1 aclitellate, near Herbettu on way to Karni [13°56'N 74°44'E], 580m, edge (forest/pasture), October 1991; 3 aclitellate, 1 clitellate, Toskar Bare [13°54'N 74°46'E], 1000m, savanna, October 1991; 1 clitellate, near Heggarse on way to Halli Bare [13°56'N 74°46'E], 660m, forest, October 1992; 1 aclitellate, 5 km west of Karni [13°55'N 74°44'E], 580m, forest, October 1992; coll. L. Lardy: 6 clitellate, Herbettu, [13°57'N 74°47'E], 690m, moderately disturbed evergreen forest, August 2001.

Diagnosis. Setae lumbricine; spermathecal pores paired at furrows 7/8/9, at or slightly lateral to a lines; genital markings paired, medially conjoined, at furrows 11/12, sometimes 15/16, 20/21; intestine begins in 19; last pair of hearts in 13; seminal vesicles in 11 and 12; prostates paired in 17 and 19; spermathecal diverticulum adherent to duct.

W. michaelseni sp. nov. is distinguished from all other species of the genus by the presence of seminal vesicles in segment 11. It is, however, closely related to W. veereshi Julka, 1988 by the combination of following characteristics: lumbricine setae throughout the body, paired spermathecal pores in furrows 7/8/9 and paired prostates in 17 and 19. Distinction from W. veereshi is provided by the location of last pair of hearts in 13, beginning of intestine one segment further backward in 19, spermathecal diverticulum adherent to spermathecal duct and in possessing genital markings. W. michaelseni is also much longer with more number of segments than W. veereshi.

Description. Length 140–280 mm, diameter 3–4 mm, 284–390 segments. Prostomium epilobic, tongue open. First dorsal pore at 13/14, sometimes 12/13. Clitellum annular, 13–½18, 18. Setae lumbricine, aa = 3.3–4.0 ab = 0.8–0.9 bc = 1.6–2.4 cd = 0.13–0.19 dd on 12, aa = 4.2–6 ab = 1.0–1.2 bc = 2.7–3.4 cd = 0.18–0.21 dd on 24. Male pores paired, minute, in seminal grooves, on 18, median to a lines; prostatic pores paired, minute, at ends of concave seminal grooves on 17 and 19, at a lines; seminal grooves almost straight or concave with concavity lateral. Female pores minute, paired, presetal, on 14, within a lines. Spermathecal pores paired, transverse slits, in 7/8/9, at or slightly lateral to a lines ( Fig. 39 ). Genital markings paired, medially conjoined with centres at about a lines, at 11/12, sometimes 15/16, 20/21.

Unpigmented. Septa 4/5 delicate, 5/6 thin, 6/7–12/13 muscular. Gizzard large, in 5. Calciferous glands absent, but oesophagus enlarged in 16–17 and internally with low calciferous ridges. Intestine begins in 19; intestinal caeca and supra­intestinal glands absent; typhlosole simple, lamelliform, 22–26 to 194–229 (169–205 segments). Dorsal blood vessel single, complete; supra­oesophageal vessel single, 7–13; extra­oesophageal vessels paired, recognised in 5, passing to ventral surface of oesophagus in 7 and uniting with paired latero­parietal vessels in 13; subneural vessel absent; last pair of hearts in 13. Holandric, testes and male funnels paired, free, in 10 and 11; seminal vesicles in 11 and 12. Prostates tubular, paired, in 17 and 19; ducts almost straight. Penial setae ( Fig. 40 ) ornamented with closely set small spines, tip pointed and slightly excavated on one side, 1.6–2.2 mm long, 30–35 diameter. Spermathecae ( Fig. 41 ) paired, in 8 and 9, each with an ental club­shaped diverticulum, adherent to duct, which is shorter than ampulla. Stomate enteronephric megameronephridia 2 pairs in each of caudal segments posterior to typhlosole region, funnels at ab (close to nerve cord) and c. Genital marking glands absent.

Reproduction. Presumably biparental.

Ingesta. Brown mineral soil with some tiny pieces of bark, twigs and roots, and few quartz and rock particles.

Ecological data. W. michaelseni is widespread in altitude grassland, edges and forests with various soil properties: OM content 3.6–9.2 g 100g ­1 soil, C/N 11.5–17.8, proportion of gravels (> 2 mm) 14–73%, clay content 19–50%, bulk density 0.86–1.27 Mg m ­3, pH (water) 4.6–5.7, cations 2.6–11.8 cmol kg ­1 soil, CEC 9.4–22.9 cmol kg ­1 soil.

Ecological category. Possibly anecic.

Etymology. This species is named after Dr. W. Michaelsen, renowned world authority on oligochaete taxonomy.

Remarks. Referred as ‘Genus A sp1’ in Blanchart and Julka (1997).

Figures

FIGURES 35 – 41. Karmiella sulvalliensis sp. nov. (35 – 38): 35, sigmoid a seta on segment viii; 36, genital region; 37, penial seta; 38, spermatheca. Wahoscolex michaelseni sp. nov. (39 – 41): 39, genital region; 40, penial seta; 41, spermatheca. Scale bar 4.0 mm (36, 39), 0.75 mm (38, 41), 0.065 mm (35, 40), 0.035 mm (37).