Andiodrilus cravijae, Celis & Feijoo & Rangel-Ch, 2018

Celis, Liliana V., Feijoo, Alexander & Rangel-Ch, Orlando, 2018, Two new earthworm species (Oligochaeta: Annelida) of the Orinoquia region of Colombia, Zootaxa 4496 (1), pp. 440-447 : 445-446

Andiodrilus cravijae , sp. nov.

( Figure 1C–I , Table 2)

Material examined. Holotype: LVCelis267, clitellate specimen. Locality : Municipality of Puerto Rondon, rural community of La Esmeralda (06°22’01.1” N, 70°50’14.4” W), altitude: 132 m asl. Collection date: 31 August 2016. Collectors: L. V. Celis . Paratypes: 6 specimens (3 adults, 3 juveniles). Locality : Municipality of Puerto Rondon, rural community of La Esmeralda.

Description. Body cylindrical. With brown-colored dorsum, holotype: length 164 mm, diameter 4.2 mm in preclitellar region, 4.0 mm at clitellum, 3.8 mm in postclitellar region (segment xl), 301 segments. Paratypes: length 152–185 mm, diameter 3.5–4.4 mm, 284–341 segments. Setae visible from segment viii; 8 per segment, in two ventro-lateral and two latero-dorsal rows, setae slightly sigmoid with node ( Fig. 1C ). Genital setae with numerous semilunar excavations ( Fig. 1D ). Distance between setae in mid-body region (segments xl–l) aa: ab: bc: cd: dd = 8.0: 1.0: 6.0: 0.8: 19.6 (holotype). Clitellum saddle-shaped in segments 1/2 xvi–xxvii, 1/2 xxviii; tubercula pubertatis in 1/2 xix –1/2 xxv ( Fig. 1E ). Male pores in segment 1/2 xix, female pores in segment xiv. Spermathecal pores visible in 6/7 and 8/ 9 in the dorsal midline. Nephridiopores in line with setae c.

Internal anatomy. Septa 6/7–8/9 thick and muscularized, 9/10–14/15 less muscularized, thin from 15/16. Septa 9/10 and 10/11 fused near esophagus, the structures of x are in the segment xi (testicles and hearts) ( Fig. 1F ). Gizzard in segment vi. Three pair of extramural, pyriform calciferous glands with laminar structure (45–50 laminas) emerging from region of esophagus of segment vii, viii, xix ( Fig. 1G ). Transition of esophagus-intestine at 20/21. Typhlosole simple, occupying 1/2 of gut diameter. Caeca absent. Three pairs of lateral hearts in segments vii, viii and ix, and four pairs of "intestinal" hearts in segments x to xiii. One pair of holonephridia per segment ( Fig. 1H ). Male funnels in testicular sac seemingly in segment xi and connected to deferent ducts. One pair of diverticles from segment xi (similar to lobes or seminal vesicles). Male ducts run along the ventral zone of body to 1/2 xix. Ovaries in segment xiii. Three pairs of spermathecae in intersegments 6/7–8/9; spermathecae with short duct and seminal chambers and oblong ampulla, the posterior spermathecae are more voluminous than the anterior ones ( Fig. 1I ).

Etymology. The species is named after the Cravo River, department of Arauca, Colombia.

Habitat characteristics. Andiodrilus cravijae sp. nov. was collected in the alluvial plain of the Puerto Rondon, Orinoquia region of Colombia. The dominant plant formations include grassland with Axonopus purpusii and Axonopus anceps growing on banks (bancos) and marsh communities dominated by especies of Eleocharis, Phyllanthus , Ludwigia . Also are present aquatic comunities with Pontederia subovata and Ludwigia sediodes .

Comments. Andiodrilus cravijae sp. nov. is close to A. pachoensis Michaelsen, 1900 in the position of the tubercula pubertatis, and to A. major Michaelsen, 1900 , in the position of the spermathecal pores and the position of the clitellum. Andiodrilus cravijae sp. nov. is close to A. pachoensis in the position of the tubercula pubertatis (1/2 xix–1/2 xxv vs. 1/4 xix, xx–xxv in A. pachoensis ) but differs in the extension of the clitellum (11 1/2 or 12 segments vs. 10 in A. pachoensis ), the position of the male pore (1/2 xix vs. 20/ 21 in A. pachoensis ), the position the spermathecae pores (in the dorsal midline vs. in line with ab). The new species has the same position of the spermathecal pores as A. major (6/7–8/ 9 in the dorsal midline) and in the position of the clitellum (1/2 xvi– xxvii, 1/ 2 xxviii vs. xvii–xxix), but differs in the extension of the tubercula pubertatis (5 segments vs. 6 in A. major ), in the position of the male pores (1/2 xix vs. xx in A. major ) and in the position of the female pores (xiv vs. xvii in A. major ) (Table 2).

Figures

FIGURE 1. Righiodrilus cusiani (A,B) and Andiodrilus cravijae spp. nov. (C–I). Righiodrilus cusiani sp. nov., holotype. A. Ventral view. B. Spermathecae. Andiodrilus cravijae sp. nov., holotype. C. Common seta. D. Genital seta. E. Ventral view. F. Internal dorsal view (Gi, Gizzard; Cg, calciferous glands; Ts, Testis sac; Sv, seminal vesicle; Lh, Lateral heart; Ih. Intestinal heart). G. Calciferous gland. H. Nephridium. I. Spermathecae.