MALACOLOGICAL SOFT-BOTTOM ASSEMBLAGES IN THE ENVIRONMENTAL PROTECTION AREA OF ARQUIPÉLAGO DE SANTANA, MACAÉ, RIO DE JANEIRO
Keywords:
In 1993, seventeen stations were sampled at Área de Proteção Ambiental in Santana's Archipelago (Macaé-RJ) using van-Veen grab and dredge. 152 taxa were identified and submitted to co-occurrence patterns analysis which showed two malacological assemblagesAbstract
In 1993, seventeen stations were sampled at Área de Proteção Ambiental in Santana's Archipelago (Macaé-RJ) using van-Veen grab and dredge. 152 taxa were identified and submitted to co-occurrence patterns analysis which showed two malacological assemblages, one representing the stations with fine sand bottoms and mud, the other one with course sand. The association of fine sand was characterized by deposit feeders as Nucula puelcha, Adrana electa and by filter feeders with long siphons like Pcriploma compressa and Macoma lenta; on the other hand, the coarse sand association was distinguished by mollusks without siphon or with short siphon as Americuna besnardi, Glycimeris longior aud Carditamera floridana. The discriminant model based on abiotic variables was 100% efficient in identifying the environment where the two assemblages occur, and variables like grain size, kurtosis and mud percentage were specially important. It is practicable to use dead collected mollusks to establish species assemblages and/or malacological homogeneous areas, since the results from the analysis that used the living collected animals compared to the results from the dead collected animals showed that only 6% of' all stations changed grouping.
