Endolithic community replacement on a Pliocene rocky coast

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Abstract
A limestone karst topography on the island of Rhodes, Greece, was flooded by a tectonically dominated transgression starting in late Pliocene time. Surfaces in contact with seawater were sculptured by communities of boring and rasping organisms. A raised cliff, studied in detail, comprises habitats such as a cliff‐foot platform, steep surfaces along the cliffline, a cave, and overhangs. Each habitat has a distinctive bioerosion sculpture. Four trace fossil suites were recognized, comprising six ichnocoenoses, the work of different endolithic paleocommunities in environments ranging from illuminated, shallow water cliff‐face to aphotic, tranquil inner reaches of the cave. As the transgression progressed, and surfaces were exposed to deepening water, new trace fossils were superimposed on old. Thirty‐one ichnospecies were identified, belonging to Caulostrepsis, Cen‐trichnus, Conchotrema, Entobia, Gastrochaenolites, Gnathichnus, Maeandropolydora, Oichnus, Phrixichnus (new), Radulichnus, Ren‐ichnus, Rogerella, and Trypanites. The bivalve(?) boring Phrixichnus phrix and the sponge boring Entobia goniodes are new. Some Gastrochaenolites contain body fossils of boring bivalves. The ichnotaxa are distributed among six ichnoguilds. The trace fossils show a range of preservation potentials according to the tier in which they were emplaced. Two ichnofacies are denned, according to site of preservation of the material: an entobian ichnofacies and a gnathichnian ichnofacies.