Coralline algal turfs commonly occur on temperate-subtropical rocky intertidal shores and function as habitat for different invertebrate taxa. Coralline algae are diverse with varied morphologies. On the rocky intertidal shore of Amakusa Shimoshima Island, Kumamoto, Japan, two coralline algae coexist sympatrically. One belongs to genus Amphiroa, characterized by the possession of branched fronds, while the other belongs to genus Corallina, with feather-like fronds. In this study, we investigated invertebrate assemblages associated with two coralline turfs to clarify differences in community structure.
Amphiroa and Corallina turfs with associated invertebrates were sampled and animals were classified and counted. Data on environmental characteristics were also obtained from sampling sites. PERMANOVA and nonmetric multidimensional scaling (nMDS) analyses were conducted to evaluate and visualize variation in faunal composition among the turf species. PAMANOVA revealed that the difference in turf species explained 13% of variation in faunal dissimilarity. This result suggested that faunal composition might be affected by turf species identity. GLMMs were applied to the abundances of top six invertebrate taxa found in each turf species. Effects of some factors on invertebrate assemblages were different between turf species. Overall, the results showed that the abundances of associated animal taxa were differences on two turf species.