ABSTRACT
The crustose coralline algae occupy several different habitats in the rocky shores. In this study morphological characteristics of these algae were related to the influence of environmental factors. The algae collection was done at Praia do Forno (RJ) using 10 m transects lines with 30 random points to quantify coralline algae. The morphological aspects were observed by a stereomicroscope and anatomic sections were prepared to identify the groups/taxons. Six morphological groups were identified being four more abundant. Hydrolithon samoënse (Foslie) D. Keats & Y. Chamberlain dominated on the littoral (53%) and sublittoral zones together with the chlorophyte Codium spongiosum Harvey and on barren rocks, exposed to wave action and high density of herbivorous sea-urchins(57-87%). Spongites sp was abundant on nearby rocky crevices on the littoral zone (39-40%). Lithophyllum sp. dominated from littoral (44%) to sublitoral zones together with Codium (43-74%) and Sargassum(74-93%). There was inconspicuous seasonal variation on the distribution of H. samoënse and Lithophyllum sp. Protuberant thalli of Lithophyllum dominated in places under high sedimentation while flat thalli of H. samoënse and Spongites dominated in areas with high herbivory. The distribution of form-functional groups in different habitats agrees with patterns associated with biotic and abiotic disturbances, expected for rocky shore communities.
Keywords:
crustose coralline algae; rocky shore; distribution; form-functional groups; habitats