Glossoscolex (Glossoscolex) araucariaensis, Feijoo-Martínez & Brown, 2023

Feijoo-Martínez, Alexander & Brown, George G., 2023, Three new Glossoscolex (Annelida: Crassiclitellata: Glossoscolecidae) in the truncatus group from the Brazilian Atlantic Forest, Zootaxa 5255 (1), pp. 220-234 : 223-224

Glossoscolex (Glossoscolex) araucariaensis sp. nov.

( Figs. 1 )

Etymology. The name of the species is given for Araucaria angustifolia , the dominant tree species of the type of vegetation in the habitat at the type locality.

Holotype. BRSC0024 , one adult found in surface soil (0-20 cm depth) in an Araucaria angustifolia tree plantation at the Três Barras National Forest , State of Santa Catarina, Brazil; 26.23353°S, 50.29291°W, 812 masl, 18 January, 2012, Priscila M. da Fonseca, coll.

Paratype. BRSC0025 , one adult in two pieces, same collection data as holotype .

Other material examined. BRSC0042 , two adults, one of them fragmented (only anterior segments, cut off after clitellum) in surface soil (0-20 cm depth) of native Araucaria forest (mixed ombrophilous forest) at the Três Barras National Forest , State of Santa Catarina, Brazil; 26.21908°S, 50.30366°W, 812 masl, 18 January, 2012, Priscila M. da Fonseca, coll.

Description. Endogeic species with cylindrical body, lacking pigmentation. Holotype: length 117.1 mm, diameter 1.6 mm in preclitellar region, 2.0 mm at clitellum, 1.9 mm in postclitellar region. Number of segments 305. Paratype: 139 mm long, with diameter 2.0 mm (segment 10), 1.6 mm (segment 21) and 1.8 mm (segment 40). Number of segments 262 (175 in piece with clitellum and 87 in piece with posterior region). The first segment is invaginated. Prolobic prostomium. Setae lumbricine, closely paired, setae a, b visible from segment 12, and c, d from 27. Setal ratio in segment 40: aa:ab:bc:cd:dd = 10:1:1.5:0.5:10. The annular-shaped clitellum lies in segments 15–23, 24 (=9, 10), with tubercula pubertatis absent ( Fig. 1A ). Male pores in segment 17 are at the tip of a genital tumescence with the shape of volcanic crater ( Fig. 1A ). Female pores are in segment 14, pre-setal, below nephropore and aligned close to setae b. The nephropores are above the setae b.

Internal anatomy. The anterior septa of the segments 6/7–10/11 are thin, conical and interpenetrated but thicker than the rest in the posterior region. Elongated and muscular gizzard in segment 6. One pair calciferous glands with round shape and composite tubular structure [(= Kompositenschlauchtaschen, see Michaelsen (1918: 50)] in segment 12 ( Fig. 1B ). Oesophagus–intestine transition begins in segment 15 and the typhlosole starts in segment 16. Intestinal caeca absent. Five pairs of hearts in segments 7–11. One pair of holonephridia per segment. Ovaries and ovarian funnels in segment 13. One pair of seminal vesicles beginning in segment 12 and extending to segment 93. Male sexual system metandric, testes and funnels in single mid-ventral subesophageal sac in 11; with vas deferens beginning in segment 11 and extending backwards above a, b setae, penetrating the copulatory chambers in segment 17, and exiting at the male pore in segment 17. Copulatory chambers, bean shaped, present in segments 17–18 ( Fig. 1B ).

Remarks. Glossoscolex (G.) araucariaensis sp. nov. is close to G. (G.) mariarum Bartz & James, 2012 (Lupionópolis, Paraná, Brazil), G. (G.) terraopimus Bartz & James, 2012 (Ortigueira, Paraná, Brazil) by the presence and position of annular clitellum and lack of tubercula pubertatis, but is separated by the shape and position of the copulatory pouches [G. (G.) mariarum : fusiform, 1/3 15-19; G. (G.) terraopimus : reniform, 15-1/2 18] vs. bean shaped, present in segments 17–18, as well as the setal distances.

Figures

FIGURE 1. Glossoscolex (Glossoscolex) araucariaensis, sp. nov. A. External view, showing clitellum (segment 15-23), the female pore (FP) region (segment 14) and the prevalent male pores (MP) on 17. B. Internal view, showing the salient (whitish) copulatory chambers (CC) occupying segments 17 and 18, the large whitish seminal vesicles (SV), the calciferous gland (CG) in segment 12 and the testes (T) in a subesophageal sac in segment 11.