Parvidrilus camachoi, Martínez-Ansemil & Châtelliers & Martin & Sambugar, 2012

Martínez-Ansemil, Enrique, Châtelliers, Michel Creuzé Des, Martin, Patrick & Sambugar, Beatrice, 2012, The Parvidrilidae - a diversified groundwater family: description of six new species from southern Europe, and clues for its phylogenetic position within Clitellata (Annelida), Zoological Journal of the Linnean Society 166 (3), pp. 530-558 : 538-540

publication ID	https://doi.org/ 10.1111/j.1096-3642.2012.00857.x
DOI	https://doi.org/10.5281/zenodo.5480036
persistent identifier	https://treatment.plazi.org/id/039ADA53-1F53-6973-FCB4-26B466E7FB48
treatment provided by	Marcus
scientific name	Parvidrilus camachoi
status	SP. NOV.

Treatment

PARVIDRILUS CAMACHOI MARTÍNEZ- ANSEMIL & SAMBUGAR SP. NOV. ( FIG. 4 View Figure 4 )

Holotype: MNCN 16.03 View Materials /3070, mature specimen, longitudinal sectioned at 0.4 Mm, stained with toluidine blue and mounted in Canada balsam. Estaragüeña cave (43°17′58.2′′N, 4°36′23.5′′W, Z 53 m asl), Puentellés, Cantabria, Spain, 4.ix.2002, leg. Ana Camacho. Etymology: Named after Ana Camacho, responsible for the PASCALIS project for the Spanish partners, in honour of her important contribution to the knowledge of European biospeleology. GoogleMaps

Description: Body wall thin (especially in dorsal part), and unpapillated. Large globular clitellar cells observed on lateral sides of XI– XIII ( Fig 4D View Figure 4 , cl); porophore and surrounding area glandular. Brain long, extending into segment IV, deeply incised posteriorly ( Fig. 4B, b View Figure 4 ). Ventral nerve cord in contact with epidermis, beneath muscles of the body wall ( Fig. 4B, C View Figure 4 , nc). Most setigeral segments have a mid-dorsal glandular pouch opening posteriorly on each segment, at or near the transversal setal line ( Fig. 4B, C View Figure 4 , gp); glandular pouches absent from IV- VI.

Digestive tract complete, entirely ciliated, and ending in a terminal anus. Eversible pharynx, with small dorsal pad set off from oesophagus, followed by a narrow winding tube extending into VIII, with thick muscular walls at about VII– VIII ( Fig. 4C View Figure 4 , oe); alimentary canal completed by a gut, clearly enlarged from segment XIII ( Fig. 4E–J, g View Figure 4 ). Compact pharyngeal glands present in IV– VI ( Fig. 4B, C View Figure 4 , pg). Digestive tract from V, surrounded by a well-developed layer of chloragogen cells. Coelomocytes and nephridia not observed.

Two narrow testes attached to septum 10/11 ( Fig. 4H–I, t View Figure 4 ). Free germ cells and morulae floating in the coelomic cavity of segment XI ( Fig. 4G View Figure 4 , mo). A small seminal vesicle in XII ( Fig. 4E, G View Figure 4 , sv). Sperm funnels not observed. A piece of vas deferens (about 1.5 Mm wide) observed near the basal part of an atrium ( Fig. 4A, F View Figure 4 , vd). Atria tubular, somewhat curved, moderately elongated (about 32 Mm long, 8–10 Mm wide), extending into the beginning of XIII ( Fig. 4A, F–J, a View Figure 4 ) merging, below the nerve cord, into a common ejaculatory duct which opens at the tip of a mid-ventral porophore located on the transversal setal line of segment XII ( Fig. 4A, G–J View Figure 4 , ed, mp, p). Atrial wall thin (less than 2 Mm thick) and muscular (?); ejaculatory duct surrounded by a thin layer of muscles. Atrial lumen filled in with a granular material (secretions?, or remains of old epithelial cells?), and with a large amount of spermatozoids, their heads distally attached to atrial wall, and their long flagella orientated to the proximal atrial end, with a clear flamigerous appearance ( Fig. 4H–I View Figure 4 , gm, sp). Prostate glands absent. Two ovaries attached to septum 11/12 ( Fig. 4E, o View Figure 4 ). A large vitellogenic mature egg in segment XII, slightly protruding into XIII ( Fig. 4E, e View Figure 4 ). Oviducts not observed. A single spermatheca is present in XIII. Spermathecal ampulla round (about 18 Mm in diameter), with a fine epithelial wall (1–3 Mm thick); spermathecal duct (about 10 Mm long) as a loosely defined structure, hollowed by a very narrow duct (?), ending near the septum 12/ 13 in a somewhat lateral position, at the left side of the worm ( Fig 4A, E–H View Figure 4 , sa, sd). Ampulla filled with spermatozoids, attached around the wall, and with a fine secretion.

Remarks: The description of external anatomy cannot be given in detail as the individual was sectioned. Nevertheless, prior to sectioning, we noted that the external anatomy of this specimen agrees in all respects with that of P. spelaeus , including size of the worm, absence of modified genital setae ( Fig. 4A, E View Figure 4 , cr), and shape and number of dorsal and ventral somatic setae.

Parvidrilus camachoi sp. nov. is one of three Parvidrilus species known so far that have a single spermatheca in segment XIII. The narrow and moderately elongated, tubular, bent atria and the roundish spermathecal ampulla filed with spermatozoids attached around the wall are diagnostic traits for this new species. The closest relative to P. camachoi sp. nov. is P. spelaeus but in the latter, atria are pyriform, the spermatheca is very large and irregular in shape, and sperm is arranged in large masses of agglutinated spermatozoids into the spermatheca.

Distribution and habitat: Parvidrilus camachoi is known only from the type locality in the Estaragüeña cave Puentellés, Cantabria, Spain. Estaragüeña corresponds to a resurgence of the Diva River. The cave is hardly accessible, as there is a siphon a few metres from the entrance of the gallery. The species was found in the entrance hall, along the edge of the siphon, in wet sands with abundant organic matter.