Annls Limnoi. 33 (1) 1997 : 33-44 Groundwater Oligochaetes from Southern-Europe. I. A new genus and three new species of Rhyacodrilinae (T\ibificidae) with a redescription of Tubifex pescei (Dumnicka) comb. n. E. Martinez-Ansemil1 B. Sambugar2 N. Giani3 Keywords : Oligochaeta, Tubificidae, new species, groundwater, Rhyacodrilus, Stochidrilus, Tubifex. Many Oligochaeta were collected during recent investigations in Southern-European caves. This is the first contribution in which some data concerning the Tubificidae are summarized. Three new species of Rhyacodrilinae, including a new genus, are described: Rhyacodrilus omodeoi n. sp., Rhyacodrilus dolcei n. sp., Rhyacodrilus gasparoi n. sp. and Stochidrilus glandulosus n. geh., n. sp. The poorly known species Frearidrilus pescei (Dumnicka 1981, augm. 1987) is redescribed on the basis of new ma• terial collected in Slovenian caves; this revision allowed the proposal to ascribe it to the genus Tubifex, considering the mono• specific genus Frearidrilus as a junior synonym of Tubifex. Les Oligochètes des eaux souterraines d'Europe méridionale. I. Un nouveau genre et trois espèces nouvelles de Rhyaco• drilinae (Tubificidae) avec une redescription de Tubifex pescei (Dumnicka) comb. n. Mots clés : Oligochaeta, Tubificidae, espèces nouvelles, eaux souterraines, Rhyacodrilus, Stochidrilus, Tubifex. Une importante collection d'Oligochètes a été récoltée lors de prospections récentes de nombreuses grottes d'Europe méridio• nale. Dans cette première contribution à l'étude de ce matériel, trois espèces nouvelles de Rhyacodrilinae, dont l'une appartient à un genre nouveau, sont décrites : Rhyacodrilus omodeoi n. sp., Rhyacodrilus dolcei n. sp., Rhyacodrilus gasparoi n. sp. and Sto• chidrilus glandulosus n. gen., n. sp. Frearidrilus pescei (Dumnicka 1981, augm. 1987), espèce peu connue, est redécrite à partir de matériel nouveau récolté dans des grottes de Slovénie; cette révision a permis de proposer l'inclusion de cette espèce dans le genre Tubifex; le genre Frearidrilus, monospécifique, est donc considéré comme synonyme de Tubifex. 1. Introduction Tubificidae. Other taxonomical, as well as faunistic and ecological data on this and other families will be Recent investigations of the groundwater fauna of published later, when all the material will be identified. many european caves ( mainly of Italy and Slovenia) In this paper, we describe three new species of Rhya• yielded several samples.of aquatic oligochaetes placed codrilus and a new genus of Rhyacodrilinae, a well di• at our disposal by F. Stoch (Museo di Storia Naturale versified subfamily of Tubificidae in subterranean wa• di Trieste, Italy). ters ( Juget & Dumnicka 1986, Giani & Rodriguez, yWe are beginning the study of that interesting collec• 1988). tion by the identification of the members of the family The study of new material of Frearidrilus pescei (Dumnicka) from a Slovenian cave allows us a redes• cription and a reappraisal of this species. Unfortunately, tubificids are often scarce in caves and difficult to collect. So, very few specimens were at 1. Departamento de Bioloxia Animal, Biol. Vexetal e Ecoloxia, our disposal for the present study. Universidade da Coruña, Campus da Zapateira s/n, 15071, A Coruña, Spain. 2. Material and methods 2. Centro Ricerche S.A.R., via Anfiteatro, 9, 37121 Verona, Italy. The material collected in different cave habitats was 3. Centre d'Ecologie des Systèmes Aquatiques Continentaux, UMR C5576 CNRS, Université Paul Sabatier, 118 route de Narbonne, F- sampled with a hand net of 100 um mesh size. The 31062 Toulouse Cedex, France. samples were fixed in the field with 4 % formaldehyde Article available at http://www.limnology-journal.org or http://dx.doi.org/10.1051/limn/1997003 34 E. MARTÍNEZ-ANSEMIL, B. SAMBUGAR, N. GIANI (2) and stored in 70 % ethanol. The specimens were stai• Type locality. «Krizna Jama» (S. 65), Loz, Cerknica, ned with Erlich's haematoxylin and either dissected Slovenia, 09-19-93, subterranean watercourse in Dez- under a stereo-microscope and then mounted in Cana• manov Rov, leg. F. Stoch. da Balsam on separate microscopic slides, or mounted Etymology whole in Canada balsam. Species named after Pietro Omodeo, to show grati• The type material is deposited in the Museo di tude to the professor who first initiate one of the au• Scienze Naturali, Trento, Italy (MTSN). thors (BS) to the study of oligochaetes, and in honour 3. Description of species of his large contribution to the knowledge of Oligo- chaeta. 3.1. Rhyacodrilus omodeoi n. sp. (Fig.l) Description Holotype. N° MTSN OLI 1, 1 mature specimen, Small species. Length 3.8-4.3 mm. Maximum width stained in haematoxylin, dissected and mounted in Ca• in anteclitellar region (slightly compressed specimens) nada balsam. 0.28 mm. Segments 37-40. Prostomium with rounded Paratype. N° MTSN OLI 2, 1 mature specimen, stai• tip, 113-125 um long, 107-137 um wide at base. Tegu• ned in haematoxylin, dissected and mounted in Cana• ment with irregular brownish spots of granular secre• da balsam. tions, mainly in the middle and posterior regions. Cli- Other material. 8 immature specimens, mounted in tellum extending over 1/2X-XII. In each dorsal bundle toto in Canada Balsam. of the anterior region (including the clitellum and the Fig.l. Rhyacodrilus omodeoi n. sp. A: somatic setae; B: coelomocyte; C: Lateral view of spermatheca and male genitalia in segments XXI. a: atrium; dV : dorsal setae of segment V; dp : posterior dorsal setae; o: ovary; pr: prostat gland; ps: penial seta; sa: spermathecal ampula; sd: spermathecal duct; sf: sperm funnel; sos: somatic setae; vd: vas deferens; vIV: ventral setae of segment IV; vVII: ventral setae of segment VII; vXII: ventral setae of segment XII. Fig.l. Rhyacodrilus omodeoi n. sp. A: soies somatiques; B: coelomocyte; C: Vue latérale de la spermathèque et de l'appareil génital mâle dans les segments X et XI. a: atrium; dV : soie dorsale du segment V; dp : soie dorsale postérieure; o: ovaire; pr: prostate; ps: soie pénienne; sa: am• poule de la spermathèque; sd: canal de la spermathèque; sf: entonnoir spermatique; sos: soie somatique; vd: canal déférent; vIV: soie ventrale du segment IV; vVII: soie ventrale du segment VII; vXII: soie ventrale du segment XII. (3) GROUNDWATER OLIGOCHAETES FROM SOUTHERN-EUROPE 35 next three to five postclitellar segments) there are 1-2 Discussion finelly serrated hairs, maximum length 240 um, and Rhyacodrilus is a large genus, where Rhyacodrilus (1)2(3) bifid or pectinate crochets (intermediate teeth omodeoi n. sp ranges among a little group of species very fine and only occasionally observed at lOOOx oil having some dorsal simple pointed crochets: R. altaia- immersion and phase contrast), with distal and proxi• nus Michaelsen, 1935, R. lindbergi Hrabe, 1963 and R. mal teeth short, about equal in length and distal thin• amphigenus Juget, 1987. R. altaianus, from the Cen• ner; in the middle and posterior regions, there are (2) 3, tral Altai, with its long hair-like penial setae and long 4, 5 (6) dorsal crochets, that became progressively cur• tubular atria is a species quite apart in the genus. ved at the distal end, and with distal tooth more and The genital apparatus of R. lindbergi, described from more reduced until it desappears in some crochets of a single specimen of a cave in Portugal (Hrabe 1963) is medium-posterior bundles and in all crochets of poste- poorly known but it seems closely resembling to that . rior dorsal bundles; dorsal crochets length = 50-66um. of the new species except for the penetration of the (4) 5, 6 (7) ventral setae per bundle in segments II- spermathecal ampullae into posterior segments obser• VIII, 1-4 in IX, 1-2 in X, 1 in XI (penial seta) and 3, 4, ved in R. omodeoi n. sp. and not mentioned for R. lind• 5 (6) thereafter; all the anteclitellar setae have distal bergi. The new species has only 1 penial seta per bund• tooth thicker and 2-3 times longer than proximal; dis• le instead of 2 (undescribed) for R. lindbergi. Accor• tal and proximal teeth are equal or distal only slightly ding to Hrabe (op. cit.), the lower tooth of the anterior longer in XII, then the distal become progressively ventral setae of R. lindbergi from segment 4 up to the thinner and shorter than proximal, and occasionally posterior end of the body is much longer than the up• desappear; ventral setae length = 55-76 um. Setae of per one, whereas in R. omodeoi n. sp. (including the medium and posterior ventral bundles are similar to immature individuals) the distal tooth of all ventral se• the corresponding dorsal ones, but ventral simple poin• tae from II to X is always 2-3 times longer than the ted setae are much more unfrequent. In the youngest proximal. Simple pointed crochets are present in all individuals observed (around 30 segments), the simple postclitellar dorsal bundles of R. lindbergi but absent pointed setae are limited to the posterior dorsal in the first segments following.the clitellum of R. omo• bundles. The penial setae have the most typical shape deoi n. sp. Pectinate setae are absent in the anteclitellar in the genus; they are 70-75 um long, straight in their dorsal bundles of R. lindbergi and present in at least proximal part (maximum width = 2.5pm), with a no- some bundles of the new species (the absence of inter• dulus placed about 1/3.5 from the distal tip, the distal mediate teeth could be only apparent as a result of part faintly curved, and always (?) simple pointed end. technical problems). Hair setae are present in some Chloragogen cells from septum V/VI. Coelomocytes postclitellar dorsal bundles of the new species, whe• abundant, sphaeric, with a clearly visible central nu• reas they are limited to the anteclitellar region in R. cleus; 7-14 um in diameter. Pharyngeal glands present lindbergi. Finally R.