Aulopora in the context of Carbonate hardgrounds

Tabulata, commonly known as tabulate corals, is a class of extinct corals.They are almost always colonial, forming colonies of individual hexagonal cells known as corallites defined by a skeleton of calcite, similar in appearance to a honeycomb. Adjacent cells are joined by small pores. Their distinguishing feature is their well-developed horizontal internal partitions (tabulae) within each cell, but reduced or absent vertical internal partitions (septa). They are usually smaller than rugose corals, but vary considerably in shape, from flat to conical to spherical.

Around 300 species have been described. Among the most common tabulate corals in the fossil record are Aulopora, Favosites, Halysites, Heliolites, Pleurodictyum, Sarcinula and Syringopora. Tabulate corals with massive skeletons often contain endobiotic symbionts, such as cornulitids and Chaetosalpinx.

An epibiont (from the Ancient Greek meaning "living on top of") is an organism that lives on the surface of another living organism, called the basibiont ("living underneath"). The interaction between the two organisms is called epibiosis. An epibiont is, by definition, harmless to its host. In this sense, the interaction between the two organisms can be considered neutralistic or commensalistic; as opposed to being, for example, parasitic, in which case one organism benefits at the expense of the other, or mutualistic, in which both organisms obtain some explicit benefit from their coexistence. These organisms have evolved various adaptations to exploit their hosts for protection, transportation, or access to resources. Examples of common epibionts are bacteria, barnacles, remoras, and algae, many of which live on the surfaces of larger marine organisms such as whales, sharks, sea turtles, and mangrove trees.

Although there is no direct effect of the epibiont to the host, there are often indirect effects resulting from this interaction and change in the surface of the host. This has been found to be especially important to marine organisms and aquatic ecosystems, as surface qualities do impact necessary ecological functions such as drag, radiation absorption, nutrient uptake, etc.