RHABDITID SPECIES (NEMATODA, RHABDITIDA) RECORDED IN PENINSULAR SPAIN AND BALEARIC ISLANDS

Members of the order Rhabditida are one of the most important taxa within the phylum Nematoda. They are very abundant and widely distributed in both soil and freshwater, where exploit different food resources: saprophagous and/or bacteriovorous (cephalobid species), predators (diplogasterid species), insect-parasites or entomopathogens (steinernematid species) and even, if we take into account the new concept of the group by De Ley and Blaxter (in press), plant-parasites (tylenchs). Rhabditid nematodes are also a highly diversified group, currently including 142 genera (cf. De Ley et al., 1998). Relatively scarce information on rhabditid nematodes from Spain is available and no monographic study of the group has been previously


Introduction
Members of the order Rhabditida are one of the most important taxa within the phylum Nematoda.They are very abundant and widely distributed in both soil and freshwater, where exploit different food resources: saprophagous and/or bacteriovorous (cephalobid species), predators (diplogasterid species), insect-parasites or entomopathogens (stei-nernematid species) and even, if we take into account the new concept of the group by De Ley and Blaxter (in press), plant-parasites (tylenchs).Rhabditid nematodes are also a highly diversified group, currently including 142 genera (cf.De Ley et al., 1998).
Relatively scarce information on rhabditid nematodes from Spain is available and no monographic study of the group has been previously

RESUMEN Especies de rhabdítidos (Nematoda: Rhabditida) citadas en España peninsular y las Islas Baleares
Se presenta una recopilación de citas previas de especies pertenecientes al orden Rhabditida en la España peninsular e Islas Baleares.Se listan ochenta especies de cuarenta géneros y doce familias.La información que concierne a cada especie contiene el nombre científico, sinonimia, distribución y observaciones.Los datos de distribución incluyen las localidades y/o áreas geográficas donde las especies han sido recolectadas, y las referencias correspondientes.También se realiza una breve discusión sobre el conocimiento de los nematodos rhabdítidos en el área ibérica, concluyéndose que la mayor parte de las especies se conocen deficientemente, siendo necesario un estudio taxonómico y/o faunístico adicional del taxon.Palabras clave: Citas, distribución, fauna ibérica, nematodos rhabdítidos, recopilación.carried out.However, a small and rather disperse volume of data is found in numerous contributions dealing with general nematode fauna, or in a few articles containing descriptions of previously known and/or new species.This paper, which is compiling the general chorological information (species, localities, references) of Spanish rhabditid species as first source of need information, is conceived as a starting point for a detailed taxonomic study of the group in Andalucía Oriental (southeastern Spain).
Previous remarks should be pointed out.(i) Only records from peninsular Spain and Balearic Islands have been compiled.(ii) Just the information appeared in papers, book articles or books has been taken into account, and not so those records found in abstracts of congress, Ph.D. Thesis, etc. (iii) Those records containing specific identifications of the taxa have been compiled, but not so others in which just generic identification of specimens is given.(iv) No taxonomic study of specimens has been undertaken for this contribution, and, as consequence, data and remarks provided are based on the available literature.(v) In general, the modern -although already classic - Andrássy's (1983Andrássy's ( , 1984) ) classification is followed for higher categories, but some more recent nomenclatorial changes have been also introduced, mainly at generic and specific levels.(vi) References to taxa authorities are omitted in the corresponding list, i.e., only those papers refering to records and their remarks are presented.

Historical outline
Although the first records of rhabditid nematodes from Spain were made by Madrid-Moreno (1911), who cited Anguillulina stercorarius in two different habitats (a garden from Madrid city and plancton from Lozoya River), and Muñoz-Medina (1945) who found Rhabditis aspera in Sierra Nevada mountains (province of Granada), the pioner of nematological studies in Spain and the first author providing morphological and chorological information of rhabtidid species was Enrique Gadea Buissan.In his Ph.D. Thesis (1952), Gadea described and recorded eleven species, and in his numerous subsequent papers he would add new species and records to the Spanish nematode fauna.In the sixties, Jiménez-Millán and collaborators (see, for instance, Arias et al., 1963;Jiménez-Millán et al., 1965) reported additional records, even describing the new genus Chitinotylenchoides Arias & Jiménez-Millán, 1968 which is later on considered a junior synonym of Tylopharynx De Man, 1876. Jiménez-Guirado (1974, 1976) and Palomo (1979) made new contributions in the seventies.In the 80s and 90s, Hernández et al. (1988), Hernández and Jordana (1990) and De Ley et al. (1994) recorded and described several rhabditid species, mainly cephalobs.Ocaña and Picazo (1991) carried out an interesting contribution to our knowledge of the species inhabiting freshwater in Sierra Nevada mountains.Finally, Navarro and Lluch (1999) have described a new species belonging to the genus Paracrobeles Heyns, 1968 from eastern Spain.

Commented compendium of previous records of rhabditid nematode species from peninsular Spain and Balearic Islands
The available information on the presence of rhabditid nematodes in Spain is compiled below.Species are alphabetically ordered according to their specific epithet.Data of each species contains four sections: scientific name, synonymy, distribution and remarks.Information concerning distribution includes the name of the localities where the species was found, the province of these localities (locality/province) and the respective reference.Appendix I shows the taxonomic position of the species, and Appendix II offers an alphabetical list of the species ordered by their generic names.Bütschli, 1873 REMARKS: See under its senior synonym R. terricola Dujardin, 1845.(Cobbold, 1884) Dougherty, 1955SYNONYMY: Pelodera axei Cobbold, 1884;Rhabditella axei (Cobbold, 1884) Chitwood, 1933.DISTRIBUTION: Quinto Real/Navarra (Monreal & Campoy, 1982).

elaboratus, Acrobeles
REMARKS: Unfortunately no description nor illustration of the species were given by the authors who recorded it, and no posterior finding is known.
REMARKS: Material described by Gadea (1952a) has a quite long body compared with the usual range of the species (L=1.2 vs L=0.45-0.60 mm), and other authors did not supply additional information of the species.Therefore, revision of this material and new collection of specimens are needed to confirm the presence of P. filiformis in the country.foetida, Tylopharynx (Bütschli, 1874)  DISTRIBUTION: Alcanar/Tarragona and Cocentaína/Alicante (Arias & Jiménez-Millán, 1968& 1973;Bello et al., 1973).
REMARKS: No additional information about this species is available.
REMARKS: Armendáriz and Hernández (1992) provided measurements and illustrations of the specimens collected in northern Spain.(De Man, 1880)
REMARKS: This is a worldwide distributed species.Although some measurements provided by Gadea (1952) are out the usual range of the species (V=47 vs V=62-68), more recent records confirm its presence in the North of the Iberian Peninsula and surely in the Balearic Islands.Monreal and Campoy (1982) and Mateo and Campoy (1983) provided measurements and/or illustrations of the material collected in Navarra.Boström, 1986 DISTRIBUTION: Sayerri Valley/Huesca (De Ley et al., 1994).
REMARKS: Gadea (1952c) described and illustrated in detail the specimens found in Castellón, and his measurements fit well with the available data of the species.Zullini, 1983 DISTRIBUTION: Sierra Nevada/Granada (Picazo et al., 1988).
REMARKS: No additional information about this species is available.DISTRIBUTION: Sierra de Gata/Salamanca (Palomo, 1979).
REMARKS : De Ley et al. (1994) recorded and described in detail this species that they identified as Cervidellus serratus, one of its junior synonyms.

Discussion
According to the expossed information the catalogue of rhabditid species forming part of the Spanish fauna (except those inhabiting the Canary Islands) includes eighty species belonging to forty genera and twelve families, that is, little more than one-fourth of the total world rhabditid genera are presented in the Iberian soils and freshwaters.However, these data should be considered as preliminary results and taken with caution due that various error sources exist.As mentioned in the introduction, no monographic study on rhabditid diversity in the Iberian Peninsula has been carried out so far, thus an increase of the inventory should be obtained in the future when these studies are developed.The information refering to forty-five species is merely chorological and/or faunistic, lacking detailed descriptions and revisions of this material.Moreover, some of the records date from the fifties and sixties of the past century and were not ever confirmed.Therefore, new surveys and collections will be necessary to ascertain the real (c) Sociedad de Amigos del Museo Nacional de Ciencias Naturales y Consejo Superior de Investigaciones Científicas Licencia Creative Commons 3.0 España (by-nc) http://graellsia.revistas.csic.espresence of a high number of species in the Iberian geography.If these actions were undertaken, the number of taxa would be likely reduced.
considered this taxon as species inquirienda.
it is valid.No additional information about this species is available.