Glossoscolex riograndensis subsp. pollulus, 2018

Bartz, Marie L. C., James, Samuel W., Steffen, Gerusa P. K., Antoniolli, Zaida, Steffen, Ricardo B. & Brown, George G., 2018, New species-group taxa of Glossoscolex (Clitellata: Glossoscolecidae) from Rio Grande do Sul, Brazil, Zootaxa 4496 (1), pp. 548-561 : 552-553

GlossosColex (GlossosColex) riograndensis pollulus Bartz & James , n. sp.

( Figures 1E,F , 2C,D )

Holotype. COFM BRRS0045 one adult, fragment of natiVe forest, Santa Maria , Rio Grande do Sul, Brazil, 29°39'44,89''S 53°54'50,36''O, 276 masl. 26 October 2009, G.P.K. Steffen & R.B. Steffen colls.

Paratype. A—COFM BRRS 0046 one adult. Same locality and collection data as holotype. B—COFM BRRS 0047 one subadult. Same locality and collection data as holotype.

Other material. COFM BRRS0048 adult, fragment of natiVe forest, Santa Maria, Rio Grande do Sul, Brazil, 29°39'44,89''S 53°54'50,36''O, 276 masl. 26 October 2009, M.P. Pontelli coll.

Etymology. The species is named from Latin for “small”.

Description. Dimensions: Holotype 31 mm by 3.5 mm at x, 3.8 mm at clitellum, 3.8 mm at xl, 134 segments; paratypes A 33 mm by 3.0 mm at x, 3.7 mm at clitellum, 3.5 mm at xl, 139 segments; paratype B 36 mm by 3.5 mm at x, 4.0 mm at clitellum, 3.7 mm at xl, 116 segments. Body cylindrical. Nontype specimen 28 mm long, 105 segments. Setae closely paired throughout; setal formula aa:ab:bc:cd:dd = 8.0:0.2:1.0:0.1:8.9. Setae commence in xi, not Well-Visible before clitellum. Prostomium prolobous. Unpigmented, Whitish. OVipores post setal, 3.0 mm apart, in line With setae a. Male pores 2.0 mm apart on xVii Within paired round eleVations (like a mound); clitellum saddle, xV–xxiii ( Fig. 1E,F ). Nephropores after clitellum in line of b.

Septa 6/7–10/11 equally thick and muscular. Alimentary canal With barrel shaped gizzard in Vi; esophagus With high cheVron-patterned lamellae Vii–xi, ValVular in xii, intestinal origin xiV; typhlosole origin xiV, in xiV–xxVi zigzag With Ventral edge bent oVer to form pockets, after xxVii simple WaVy lamina. Calciferous glands paired xii, small heart shaped, pedunculated, composite-tubular type; blood Vessels to gland include large branch of dorsal Vessel to approximate center of each gland. Holonephric, Vesiculate; ducts to body Wall near leVel of b; some nephridia in the anterior segments (Vi and Vii) Were full of sperm (iridescent material) ( Figure 2C,D ).

Vascular system With Ventral trunk, single dorsal trunk, lateral Vessels in Vii–ix, esophageal hearts in x–xi, last pair (xi) free. Extra-esophageal Vessel from pharyngeal glands, along Ventral-lateral face of gizzard, esophagus back to calciferous glands; supraesophageal Vessel in x–xi.

OVaries, oVarian funnels free in xiii. Male sexual system metandric, testes and funnels in xi united Ventrally in a sac shifted posteriorly to xii; seminal Vesicles tubular With lobulated edges passing through xii–xiii ranging posteriorly along intestine farther than xxxV–xxxix; Vasa deferentia long, looped from seminal Vesicles in xii, form dense zig-zag on body Wall in route to middle-anterior face of muscular round copulatory bulbs (0.7 mm diameter); bulbs extend oVer xVi–xViii. Copulatory bulbs With thin muscular outer layer, dense, delicate corrugated glandular inner surface With small lumen leading to male pore at approximate center of bulb connection to body Wall; transVerse muscle bands crossing oVer bulbs in the anterior and posterior face.

Remarks. Glossoscolex (Glossoscolex) r. pollulus is close to Glossoscolex (G.) minor Zicsi & Czusdi, 1999 considering the small body size (comp. Table 1). The differences betWeen G. (G.) r. pollulus and G. (G.) minor are as folloWs, With the characteristics of the latter in parentheses: number of segments 116–139 (198–231), clitellum saddle (annular), clitellum extension xV–xxii (xiV–xxiii), testis sacs U shaped sac in xi–xii (unpaired in xi), seminal Vesicles big tubular With lobulated edges until xxxV–xxxix (band until l), copulatory bulbs round (elongated).

G. (G.) r. pollulus is morphologically Very similar to G. (G.) r. riograndensis, With the main difference being body length, Which is smaller in G. (G.) r. pollulus (31–36 mm) than in G. (G.) r. riograndensis (53–54 mm). Furthermore, the shape of the copulatory bulbs in G. (G.) r. pollulus is round, While in G. (G.) r. riograndensis it is round to oVal ( Table 1). Both subspecies haVe sperm storage in the nephridia, but in G. (G.) r. pollulus it is more anterior segments (Vi and Vii) than in G. (G.) r. riograndensis in xii, xiii. We deemed these differences not to be enough for separation at species leVel, and furthermore, We did not haVe DNA tissue material from G. (G.) r. pollulus to compare With G. (G.) r. riograndensis . Further sampling and both morphological and DNA analysis should help reVeal possible differences betWeen these tWo subspecies, and if they correspond or not to different species.

For comparison of G. (G.) r. pollulus With G. (G.) r. nativus , see beloW.

Figures

FIGURE 1. Glossoscolex (Glossoscolex) riograndensis n. sp.. A, B. Glossoscolex (Glossoscolex) riograndensis riograndensis. C, D. Glossoscolex (Glossoscolex) riograndensis nativus n. ssp. E, F. Glossoscolex (Glossoscolex) riograndensis pollulus n. ssp. FM = female pOres; MP = male pOres; NF = nephridial pOres.

FIGURE 2. Sperm-filled nephridia Of Glossoscolex (Glossoscolex) riograndensis n. sp., histOlOgical sectiOns. A, B. Glossoscolex (G.) riograndensis riograndensis n. sp., segment xii (A) and xiii (B). C, D. Glossoscolex (G.) riograndensis pollulus n. ssp., segments Vi (C) and Vii (D).