Priodoscolex maduraiensis Ahmed & Marimuthu, 2025

Priodoscolex maduraiensis Ahmed & Marimuthu View in CoL , sp. nov.

http://zoobank.org/ urn:lsid:zoobank.org:act:2F7495D8-B95E-4F48-B796-54C989FB3065

( Figs 4–5 View FIGURE 4 View FIGURE 5 )

Type material. Holotype. Clitellate ( ZSI–GNC – An8036/2 ), Madurai (9.923514°N, 78.108583°E), Madurai district, Tamil Nadu, India; 133m above mean sea level; 8 November 2004; leg. C.K. Mandal and S. Dhani. GoogleMaps Paratypes. 14 clitellates, 2 aclitellates and 16 tail parts ( ZSI–GNC – An8037/2 ), collection details as same as holotype GoogleMaps .

Other material. 5 aclitellates ( ZSI–GNC – An3038/2 ), Yercaud (11.774038°N, 78.216717°E) (habitat coffee plantation), Salem district, Tamil Nadu, India; 1438 m above mean sea level; 30 November 2004; leg. A. Mishra and party. GoogleMaps 1 aclitellate ( ZSI–GNC – An3039/2 ) Nagalur village (11.796355°N, 78.216404°E), Yercaud, Salem district, Tamil Nadu, India; 1412 m above mean sea level; 30 November 2004; leg. A. Mishra and party GoogleMaps .

Etymology. The species epithet “ maduraiensis ” is derived from the name of the city, Madurai where the specimens have been collected. The rationale behind the species’ name is the history of the city, Madurai had been recorded by the Greek envoy, Megasthenes as early as the third century BCE ( Zvelebil 1992).

Diagnosis. Large sized; length 92–280mm; width 3–6mm, number of segments 211–389. Segment 7 biannulate, 8–12 with light annuli (two anterior and two posteriors of setal arc and one with setal arc). Colour, light brownish with reddish clitellum (preserved specimens). Prostomium prolobous. First dorsal pore in intersegmental furrow 10/11. Setae perichaetine; on the pre-clitellar region there is no dorsal or ventral setal break, post clitellum dorsal zz = 2–2.5 yz; except segment 18, the ventral most setae on segments 12–21 some time on segment 11 and 22 displaced anterior and posterior to the setal line; ventral most setae on segment 18 absent. Clitellum prominent, reddish colour, saddle shaped on segments 13–18, dorsal pores absent, 5–6 setae on each side visible ventral part of clitellum. Female pores paired in a small bulge oval area on segment 14 anterior to setal arc. Male pores closely paired on segment 18, no setae between male pores. Spermathecal pores 3 pairs, closely paired about the level of ab setal line, in segments 7,8 and 9, just posterior to the intersegmental furrow 6/7/8/9. Genital markings absent, except light bulging of ventral area on segments, 14,15,16, at the place of displaced setae. Typhlosole begin in segments 26–28. Spermathecae, three pairs in segments 7,8, and 9 sometime anterior diverted in segments 6, 7, and 8; ampulla club shaped with digitiform ectal diverticulum. Calciferous glands 4 pairs in segments 14, 15, 16, and 17, the glands in segments 15–17 are bilobed, whereas glands of segment 14 are small and single lobe. Penial setae absent.

Description. External: Colour light brownish with reddish clitellum (preserved specimen). Dimensions: Holotype: length 275 mm; width 5 mm at segment 8, 4.7 at clitellum and 4.2 at segment 20; number of segments 308; paratypes: length 92–280mm, width 3–6mm, segment 211–389; other material: length 97–208mm, width 3– 3.5mm, segments 316–376. Prostomium prolobous ( Fig. 4C View FIGURE 4 ). First dorsal pore in intersegmental furrow 10/11. Setae Perichaetine, 32 on segment 2, 74 on segment 6, 86 on segment 12, 96 on segment 19. On the pre-clitellar region there is no dorsal or ventral setal break, post clitellum dorsal zz = 2 yz. Further, the ventral setae on segments 11–20, except segment 18 displaced anterior and posterior to the setal line. Ventral most setae on segment 18 absent. Clitellum prominent, reddish colour, saddle shaped on segments 13–18, dorsal pores absent, 5–6 setae on each side visible ventral on the clitellum thickening ( Fig. 4A, B, D View FIGURE 4 ). Female pores paired, pre-setal on segment 14, nearly equi-distance between 13/14 and setal arc of segment 14. Male pores closely paired on segment 18, no setae between male pores, seminal grooves absent ( Fig. 4B, D View FIGURE 4 ). Spermathecal pores 3 pairs, closely paired at ab, in segments 7,8 and 9, just posterior to the intersegmental furrow 6/7/8/9 ( Fig. 4B View FIGURE 4 ). Genital markings absent, except epithelium bulging at ventral areas on segments, 14,15,16 and 17, at place of displaced setae. Penial setae absent.

Internal: Septa 6/7–11/12 strongly thickened, septa 5/6 and 12/13 thickened. Gizzard large cylindrical in segment 5. Intestine begin in segment 19. Typhlosole simple, lamelliform, begin in segment 28 ending in segment 204. Calciferous gland extramural, 4 pairs in segments 14–17 ( Fig. 5A, C View FIGURE 5 ). The calciferous glands of segment 14 are small in seize each with a single lobe, whereas, the glands of segments 15,16,17 are bilobed and well developed communicating dorsally, open into the intestine laterally. Nephridia meroic. Large cluster of enteronephric paired tufts in segments 4 and 5; exonephric paired tufts in segments 3 and 6–13 located at the anterior side of septa 3/4 and 6/7–13/14, open ventrally through long duct; several exonephric nephridia on the body wall of segment 14 to the last segment. Megameronephridia absent. Last pair of hearts in segment 12. Dorsal blood vessel complete, extend to the segment 3. Subneural trunk present, turning lateral in segment 15, join the latero-parietal vessel in segment 13. At segment 14 the subneural vessel branched, leave two branches on parities of segments 15 and 16 and one branch diminish posterior in segment 17. Ovaries and funnels in segment 13, ovaries grapes like, attached with posterior face of septa 12/13. Holandric, testis (testes free) and funnels in segments 10 and 11 ( Fig. 5A View FIGURE 5 ). Seminal vesicles in segments 11 and 12 (5A, C). Prostates tubulo-racemose, flattened, extend in segments 18–20; duct c shaped, curved, about 3 mm long; vas deferens join the prostatic duct ectally in segment 18 ( Fig. 5C View FIGURE 5 ). Spermathecae unidiverticulate, anterior directed in segments 6,7 and 8; spermathecal duct short, ampulla sacular, nearly club-shaped; digitiform, ectal diverticulum, about 2/3 length of duct and ampulla ( Fig. 5A, B View FIGURE 5 ). Penial setae absent.

Distribution. India: Tamil Nadu State: Madurai District: Madurai; Salam District: Nagalur.

Remarks. The new species is differentiated ( Table 1 View TABLE 1 ) from the known species Priodoscolex montanus Gates, 1940 by the number of spermathecal pores (3 pairs vs 2 pairs), origin of typhlosole 26–28 vs 27–31. Extension of clitellum 13–18 vs 13–19. Posterior dorsal break vs anterior dorsal and ventral setal break.