Pires, F. 2007. Taxonomy, abundance and distribution of sponges (Filo Porífera) in the Algarve coast. 

1. Sponges occur all over the world, in almost every aquatic habitats and at all depths. Since the interest in this animals has grown in the pharmaceutical industry and in the monitorization of ecosystems it is necessary a profound study in both an ecological and a taxonomical level. 2. Although the available information is quite scarce, it is known that physical factors such as light affect the Porifera distribution. Consequently, with the data obtained from RenSub project I and II from CCMAR, seasonality, area and depths were studied for marine sponge distribution. The sampling area corresponded to two distinctive regions: from Albufeira to Vale do Lobo and from Galé to Barra Nova do Ancão, from 0 to 30m depth. PRIMER v6 (Plymouth Routines in Multivariate Ecological Research) was used to analyse the data obtained. Phorbas fictitius was the species with higher occurrence frequency, followed by Scopalina lophiropoda. There were no significant differences in species composition between seasons (p = 0,103), which indicates that seasonality does not influence the distribution of marine sponges. There were significant differences in the composition of species (p = 0,001) between the studied areas. The most relevant differences found were between Albufeira and Celas, and between Anzol and Greta. These two last locations are very close to each other and have the same depths, differing only in the topology of the sea floor, which indicates that the spatial variation is important in the distribution of sea sponges. There was a significant variation in the species composition between the several depths’ ranges studied (p =0,004), showing that sponge distribution is strongly correlated with depth. A distribution pattern was also observed for species’ diversity and abundance, being characterized by low values at depths inferior to 10m, increasing to a maximum close to 15m and decreasing at higher depths. 3. In the taxonomical study the samples were collected using scuba diving equipment, in a 60m transect. The specimens were photographed in situ and in the laboratory, being stored individually in 70% alcohol. To allow a better observation of the sponge’s skeleton structures, tangential and transversal cuts to the sponge surface were made using histological Araldite as medium. A new procedure was used in this study, using disposable pipets to collect the spicules, thus increasing the safety of this procedure and also the amount of collected spicules. Of the 37 identified species six new records for Portugal and other two for the continental area of Portugal were discovered: Axinella guiteli, Crella fusifera, Dictyonella incisa, Dictyonella marsillii, Dictyonella plicata, Hymeniacidon mammeata, and Mycale lingua and Spongionella pulchella, respectively.