Glossoscolex demetrioi, Dudas & Feijoo & Brown, 2025

Dudas, Rafaela Tavares, Feijoo, Alexander & Brown, George G., 2025, Four new large Glossoscolex (Clitellata: Glossoscolecidae) earthworms from Brazil, Zootaxa 5589 (1), pp. 301-320 : 313-314

Glossoscolex demetrioi sp. nov. Dudas, Feijoo & Brown

( Figures 12 , 13 and 14 )

Holotype. Brazil, one adult specimen, São Luís do Paraitinga, São Paulo, Serra do Mar State Park ; latitude/longitude: 23°20’35.1”S, 45°07’27.9”W, August 2021; J.P. Villani coll. Sample ID: MZUSP6433 (formerly BRSP0945 of COFM).

Paratype. Brazil, one juvenile specimen, same collection data as holotype. Sample ID: MZUSP6435 (formerly BRSP0944 of COFM) .

Etymology. The name of the species is a tribute to researcher Dr. Wilian Carlo Demetrio (University of São Paulo) for his many contributions to the knowledge of soil fauna and earthworm ecology in Brazil.

External morphology. Holotype: Body length 528 mm after ethanol fixation. Body mass: 177.9 g (fresh weight in alcohol). Segments 364, with intersegments. Diameter: 25.5 mm in the pre clitellar region (segment X), 27.3 mm in the clitellum (segment XVI) and 24.5 mm in the post clitellar region (segment XXX). Paratype: length 298 mm after fixation, body mass: 121.3 g. Number of segments: 231. Diameter: 16.3 mm at segment X, 14.4 mm at the clitellum (XVI) and 11.1 mm in segment XXX. Body shape cylindrical, with pigmentation on dorsal size, with stripes, some dark and others lighter in color, similar to zebra patterns over the full length of the body ( Figure 12 ). Prostomium proebilobic. Setae begin widely paired, visible from segment IX onwards ( Figure 13A ). Setal arrangement aa:ab:bc:cd:dd, 22:1.1:12.4:1:23 at segment XXX. Clitellum in XV–XXIV, saddle shape ( Figure 12 ). No genital markings present. Female pores not seen. One pair of male pores on 18/19 ( Figure 13B ), on B line, with 8.1 mm distance in between. Nephridiopores near B line.

Internal morphology. Septa membranous in 6/7/8/9/10/11, strongly attached to the body wall, 14/15/16 thin and weak ( Figure 13C ). Gizzard in VI, average size (width x length) of 8.3 x 6.7 mm, occupying 1/3 VIII externally. Calciferous glands one pair in XII, below seminal vesicles ( Figure 13C ), of tubular composite type. Intestine commences in XV without different regions and with typhlosole beginning on segment XXII. Esophageal hearts in X–XII, with dorsal esophageal connection, close to testes sacs, below septa. One pair of nephridia per segment. Testes sacs large in XI, with a very visible vas deferentia connecting to the copulatory bulb. Seminal vesicles starting in XII and ending in XXVI. Spermathecae absent. Ovaries in XIII, of small size. One pair of copulatory bulbs, in oval shape in XVI–XIX ( Figure 14 ).

Remarks. The coloring pattern in Glossoscolex demetrioi sp. nov. is quite unique and an important characteristic that differentiates it from other species. The clitellum is similar to Glossoscolex demeijeri sp. nov., also starting in segment XIV, but ending in segment XXIV. The testes sacs are a large pair located in segment XII, differing it from other species like G. paulistus , G. robustus (unpaired, XI), G. amomee , and G. giganteus australis (pair, XI). However, they are similar to those in the type species Glossoscolex giganteus and G. klossae , for instance.

Figures

FIGURE 12. External view of the large, “striped” Glossoscolex demetrioi sp. nov. holotype, from the Atlantic Forest in the Serra do Mar State Park in São Luís do Paraitinga, São Paulo. Photos: Beatriz da Silva Vanolli.

FIGURE 13. Glossoscolex demetrioi sp. nov. Holotype. A. External view, setae (St) arrangement, inside the red circles. B. External view of one of the male pores (MP). C. Overview of internal structures, septa, VII–X; copulatory bulb, XVI; calciferous gland, XII; intestine, XV. In the bottom of the picture, in the red square, the pigmentation striped pattern on the dorsal portion. St: setae, Sp: septa; CB: copulatory bulb; CG: calciferous gland; In: intestine.

FIGURE 14. Glossoscolex demetrioi sp. nov. Holotype. Close up view of a copulatory bulb.