Andiorrhinus (Turedrilus) duranti, Feijoo & Brown & James, 2017

Feijoo, Alexander, Brown, George G. & James, Samuel W., 2017, New species of Andiorrhinus Cognetti, 1908 (Oligochaeta: Rhinodrilidae) from Venezuela and Brazil, Zootaxa 4363 (1), pp. 55-78 : 64-66

Andiorrhinus (Turedrilus) duranti sp. nov.

( Figure 4A–C )

Material examined. Holotype: Clitellate specimen (MZUSP 01482). Paratypes: 3 juveniles, 2 subadults, 4 adults, one of which was fragmented ( MZUSP 01483 ). Locality: Venezuela, state of Mérida, forest of Psidium caudatum ( Myrtaceae ), beside the Núcleo Universitario " La Hechicera ”, Universidad de Los Andes (08º38'00"N; 71º09'30"W). Altitude: 1950 m a.s.l. Collection date: 18 April 1994. Collector: Pedro Durant.

Etymology. The new species was named in honor of Professor Pedro Durant of the Universidad de Los Andes, Venezuela.

Description. Epiendogeic species, with yellow-colored dorsum and red-colored clitellum, which correspond to the respective color code numbers 231 and 106 ( Seguy 1936), and cylindrical body. Holotype: The length of the preserved holotype is 218 mm. Its diameter is 7.9 mm in the preclitellar region, 7.7 mm in the clitellum, and 6.2 mm in the postclitellar region. Number of segments: 129. Paratype: 170 mm long and widths of 7.4 mm (segment 9), 6.9 mm (segment 19) and 6.2 mm (segment 30). Number of segments: 164. The first segment is invaginated and the whitish, elongated, lobe-shaped prostomium measures 1.8 mm. Four pairs of setae are visible as of segment 6.

The common setae measure 0.91 mm and are slightly curved, presenting seven rectangular-shaped markings that adorn the tip region ( Fig. 4A ). The distance between the setae in segment 40 is aa:ab:bc:cd:dd = 10.5:1.0:11.5:0.8:43.0 and, in the posterior region in segment 204, it is 2.0:1.0:4.7:0.2:9.8 and in segment 100, 7.0:1.0:6.7:0.7:32.6. The setae of segments 7–9 and 19–23 are modified as genital setae and are contained in long follicles, located surrounded by five pairs of glandular masses in segments 19–23. Genital setae measure 2.14 mm and are slightly curved at the base and then rectilinear, ending in a needle-shaped tip. Ornamentation consists of parallel contoured grooves with pronounced gaps ( Fig. 4B ).

The saddle-shaped clitellum measures 15 mm and lies in segments 16–25 (=10), with the tubercula pubertatis located in segments 18–23 (=6). The male pores are located in segment 20 and female pores in segment 14. The nephropores are aligned with setae c and d. Two pairs of spermathecal pores were observed in intersegments 6/7 and 7/8, above the line of setae b.

Internal anatomy. The anterior septa of segments 6/7–14/15 are thick, conic, and nested, becoming thin and very fragile after 15/16. The round muscular gizzard and thick musculature are present in the cavity of segment 6. Three pairs of calciferous glands of lamellar internal structure are present in segments 7–9. The gland is connected to the esophagus by a long, sac-shaped duct, no appendage, each gland with 30–34 parallel lamellae. The esophagus-intestine transition begins in segment 26 and the S-shaped typhlosole begins in segment 27, occupying ½ of the intestinal lumen. There are no intestinal caeca. Three pairs of lateral hearts are located in segments 7–9 and two pairs of voluminous intestinal hearts, in segments 10 and 11. Both supraesophageal and subesophageal vessels are present. There is one pair of holonephridia per segment.

Two pairs of oblong testis sacs contain the testes in segments 10 and 11, and two pairs of seminal vesicles are present in segments 11 and 12. The two pairs of deferent ducts open towards the male pore in intersegment 17/18.

One pair of ovaries is present in the cavity of segment 13; the female pore is unrecognizable. Two pairs of very long, tongue-shaped spermathecae are present in segments 7 and 8. The duct is longer than the ampulla and, up to 2/3, presents numerous seminal chambers. The ampulla opens ovoidly, allowing the abundant sperm inside to be seen ( Fig. 4C ).

Remarks. Andiorrhinus (Turedrilus) duranti sp. nov. is closely related to A. (T.) brunneus (Michaelsen, 1892) and A. (T.) meansi James, 2009 due to the position of the clitellum and the tubercula pubertatis. The new species is distinguished by the extension of the clitellum and tubercula pubertatis, the shape of the spermathecae, shape and size of the normal setae and ornamentation of the genital setae. Furthermore, the new species is much smaller than A. meansi and of a different color.

Figures

FIGURE 4. Andiorrhinus (Turedrilus) duranti sp. nov., holotype. A. Common seta, segment 35. B. Showing genital seta a, segment 8; C, spermathecae of 7, 8.