Glossoscolex (Glossoscolex) mariebartzae Dudas, James & Brown, 2025

Dudas, Rafaela Tavares, James, Samuel Wooster, Bartz, Marie L. C. & Brown, George Gardner, 2025, New earthworm species of Glossoscolex Leuckart, 1835 and Fimoscolex Michaelsen, 1900 (Clitellata: Glossoscolecidae) from southeastern Brazil, Zootaxa 5589 (1), pp. 321-345 : 323-325

Glossoscolex (Glossoscolex) mariebartzae Dudas, James & Brown sp. nov.

( Figures 2 , and 3)

Holotype. Brazil, one adult, Minas Gerais, Itamonte, Bairro Vargem Grande, pasture soil with Araucaria trees within the Itatiaia National Park ( Figure 2A ), in the soil; latitude, longitude: 22°19”40.68’S, 44°43”57.42”; 1,771 m asl; 11 February 2009; S.W. James, G. G. Brown, M.L.C. Bartz & S.K. Dadivson coll. Sample ID COFM BRMG0494 .

Paratype. Brazil, one adult, Minas Gerais, Itamonte, Bairro Vargem Grande , same information as the holotype, with elevation: 1,821 m asl; 11 February 2009; S.W. James, G.G. Brown, M.L.C. Bartz & S.K. Dadivson coll. Sample ID: MZUSP 6437 (former COFM BRMG0063 ) .

Other material. Brazil, three juveniles; Rio de Janeiro, Resende , old growth forest, in the soil; latitude, longitude: 22°24'58.0"S, 44°31'58.4"W; elevation: 590 m asl; 11 February 2009; D. Baretta, J.M. Pereira coll. Sample ID: COFM BRRJ0565 .

Etymology. The species is named after Dr. Marie L.C. Bartz, for her long-standing contributions to earthworm biology, ecology and systematics in Brazil.

External morphology. Holotype: body length 71 mm after ethanol fixation, body mass: 0.06 g, Diameter: 2.5 mm in pre clitellar region (X), 2.6 mm at the clitellum ( XV) and 2 mm in the post clitellar region ( XXX), number of segments 75 ( Figure 2B ). Paratype: length 191 mm, body mass: 0.2 g. Diameter on segment X: 1.5 mm, at XV 1.8 mm and in the post clitellar region 1.6 mm. Number of segments 186. Body shape cylindrical, with no pigmentation. Prostomium prolobic. Setae closely paired, all setae starting in XII. Setal arrangement, at XXX-L, aa:ab:bc:cd:dd 8:1:4:1.5:7; Clitellum in XV–XXIII, annular shape ( Figure 3A, B ). Genital markings are only in the male field, on AB line. One pair of male pores on ventral position in XVII, in B line, 0.7 mm apart, and within a deep groove ( Figure 3A ). Female pores in XIV, just near b setae, very small. Nephridial non vesiculate pores in B line.

Internal anatomy. Septa 5/6 thin, slightly muscular in 6/7, then muscular in 7/8/9/10 and returning to slightly muscular 10/11, remaining septa all membranous ( Figure 3C ). A strong cylindrical gizzard in VI, with an average size (width x length) of 0.6 x 0.3 mm. One pair of calciferous glands very closely paired in XII, of composite-tubular type, sessile on the dorsal esophageal wall, large blood vessels paired on top of it, gland opening to the esophagus near dorsum. Esophagus-intestine transition in XV; intestine without caeca. Typhlosole originates with the intestine, in XV, very thick in XV–XX, tight cupped folds and after segment XX, where it changes to a simpler form, flat blade that becomes thinner and lower. Esophageal hearts in X–XI, single dorsal trunk, lateral vessels in VII–IX, supraesophageal vessel not seen. Excretory apparatus with one pair of nephridia close to the body wall and in XII–XVI they are enlarged with sperm, bigger/gigantic in the right side and smaller/modest in the left side of each segment ( Figure 3D ). Testis sac single and large in XI. Seminal vesicles in XII, long tubes run laterally to intestine ( Figures 3C ). Spermathecae absent. One pair of copulatory bulb of oval shape in XVII to XVIII ( Figure 3C, D ).

Remarks: G. mariebartzae sp. nov. belongs to the Glossoscolex subgenus and the truncatus species group, with intraclitellar male pores in segment XVII ( Righi and Lobo 1979). The male pore region of G. mariebartzae sp. nov. is relatively unique, in that the male pores are found within a groove surrounded by a single elliptical muscular region associated with the two internal copulatory pouches. Therefore, the male pores are closely paired rather than set far away from each other, as is often the case in other Glossoscolex (Glossoscolex) species. Another remarkable characteristic are the modified nephridia utilized for sperm storage, which may serve as an alternative to the absence of spermathecae, as proposed by Bartz et al. (2018). Up to now this characteristic had not been observed in other species, except G. riograndensis . The annular clitellum of G. mariebartzae sp. nov. in XV–XXXIII is a feature shared with only three other species: G. embrapaensis , G. mariarum and G. terraopimus . However, the new species has an unpaired testis sac in segment XI, a feature shared only with G. embrapaensis , as the other three species have a pair of sacs fused ventrally in XI. Nevertheless, the copulatory bulb of G. embrapaensis (segments XVIII–XXI) is much larger than that of G. mariebartzae sp. nov., which occupies only two segments (XVII–XVIII).

Figures

FIGURE 2. A. Habitat of Glossoscolex mariebartzae sp. nov., with Araucaria angustifolia trees (foreground) growing in native grasses and within the high-altitude Altantic rainforest in the Itatiaia National Park (background), Itamonte County, state of Minas Gerais. B. Recently collected specimens of G. mariebartzae.

FIGURE 3. Glossoscolex mariebartzae sp. nov. Holotype. A. External ventral view showing the male pores (MP) in each of the extremities of the slight protuberance, in XVII and the Clitellum (Cl). B. External lateral view of clitellum (Cl). C. Internal anatomy of dorsal view, showing large seminal vesicles (SV) starting in XII and copulatory bulb (CB) in XVII. D. Modified nephridia (N), with iridescence, possibly due to sperm storage.