Abstract
This work is a contribution to the knowledge of freshwater sponges (Porifera, Demospongiae, Spongillidae) of the Douro River watershed. Specimens were found in 24 of 32 transects in 16 sampling stations. Distribution and several ecological data were obtained in 25 wadeable river transects (20+/5−) and 7 deep lakes (4+/3−) of six sub-basins of the northern Iberian plateau. Four species ( Ephydatia fluviatilis, E. muelleri, Heteromeyenia baileyi and Spongilla lacustris ) were recorded throughout the survey during successive dry sessions and classified by microscopic observation of siliceous sclera. The maximum species richness was found in the Negro River, where sympatric coexistence was detected in three species. E. muelleri was only found in the Aliste River, and it is the first record of this species in the Douro basin. H. baileyi showed a preference for shallow areas in flowing waters, and was only present on hard stony substrates (quartzites). S. lacustris and E. fluviatilis were found on compacted sediments, rocks and submerged wood substrates, and in a wide interval of depths. E. fluviatilis was absent in mountain lakes, whereas it was the most frequent species in rivers. H. baileyi and S. lacustris showed preference for acidic and low mineralization rivers, while both species of Ephydatia for more mineralized waters. The influence of chemical water and other environmental parameters on the distribution range of each species and its presence in syntopy with other invertebrate indicators of oligotrophic conditions, acidity and high oxygenation in water is remarked.
Highlights
This work is a contribution to the knowledge of freshwater sponges
several ecological data were obtained in 25 wadeable river transects
The maximum species richness was found in the Negro River
Summary
Las muestras de esponjas vivas fueron recogidas en sucesivas campañas de trabajo en las subcuencas fluviales del Duero situadas en la parte más occidental de Castilla y León (Fig. 1). Fig. 1.— Localización de los tramos de las subcuencas fluviales en las que se estudiaron las esponjas, tipos de masas de agua y ubicación y red a la que pertenecen las estaciones de seguimiento de la calidad del agua (www.chduero.es) utilizadas (referencia en Tabla 1). Se han hallado en la parte de la demarcación del Duero en la que se ha trabajado cuatro de las seis especies citadas para la Península Ibérica en la monografía de Traveset (1986), única referencia hasta la actualidad sobre la fauna dulceacuícola de poríferos en este ámbito. Tabla 1.— Encuadre hidrográfico de los ecosistemas, estación referencia para los datos de calidad del agua (Fig. 1) y presencia (+) de las cuatro especies de poríferos dulceacuícolas. Table 1.— Ecosystems hydrographic framing, reference data station for water quality (Fig. 1) and presence (+) of the four species of freshwater sponges
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
