Malacofauna associada às ascídias do Golfo do México

Abstract

In the benthic environment, the ascidians have a sessile habit and can dispute or share the substrate with various organisms, including molluscs, maintaining both harmonic and disharmonious ecological relations. The Ascidiacea class possesses chemical defenses in the tunic as a protection strategy, characterized as a process of allelopathy, involving, therefore, the production of secondary metabolites. Few studies were carried out with a focus on the relation between ascidians and molluscs. The goal of this study was to know the malacofauna associated to the Ascidiacea class through samples collected by SCUBA or dredging in the years 1966, 1967, 1969, 2001 and 2012 in the Gulf of Mexico, Florida (USA). A total of 355 lots with samples of ascidians were analyzed in order to find molluscs attached to the tunic. After analysis, only 23 lots were found containing associated malacofauna, belonging to the 15 species (Gastropoda specie 1, Calliostoma aff. pulchrum, Bivalvia specie 1, Entodesma brasiliense, Plicatula gibbosa, Chama sinuosa, Chamidae sp., Chama sp., Pseudochama sp., Diplodonta cf. notate, Musculus lateralis, Chione cancellata, Anadara secernenda, Arca zebra, Ostrea cf. puelchana), with them being partially or totally involved by the ascidians. In addition, it is worth mentioning the discovery of a new record (Ostrea cf. puelchana) for the Gulf of Mexico. In this way, the study developed here provides information that may be of great relevance for the increase of ecological studies related to the association of molluscs and ascidians.