Corals, solenoporaceans (including rodolites), calcareous sponges. Sometimes associated microbes.
Bioherms around 50-60 m thick.

Reef growth limited to upper Callovian - lower Oxfordian according to ref. 1529.
Abstract of ref. 1529.
Rich and various crinoidal assemblages existed at Callovian-Oxfordian time in the Sudak environs on Crimea. 22 species are described: Dolichocrinus aberrans, Eugeniacrinitescaryophilites, E. quenstedti, Pilocrinus moussoni, Cyrtocrinus nutans (order Cyrtocrinida), Millericrinus annulatus, M. convexus, M. echinatus, M. etalloni, M. goupilianus, M. granulosus, M. knorri, M. milleri, M. multipunctatus, M. rotiformis, M. thiollieri (order Millericrinida), Balanocrinus dumortieri, B. subteres, Margocrinus modestus, Chariocrinus? burgundicus, Isocrinus amblyscalaris and 'Pentacrinus' cingulatissimus (order Pentacrinida). The described species belong to two ecological  types: cirriferous (long-stalked plastic, long-stalked immovable and short-stalked forms) and cirriless (long-stalked and short-stalked). Crinoids occupied four trophic tiers and inhabited four types of the biotopes: interreef depressions, interreef rises, reef slopes and reefs. A certain connection exists between biotope types, trophic tiers of crinoids and their ecological types. Tubular worms, bryozoans, bivalves, sponges and corals were settling on crinoid stalks in a certain sequence during the lifetime of crinoids or after their perishing. Millericrinid stems were damaged by parasites, predators and scavengers. Pentacrinid stems were twisted, depending on the environmental dynamics. Atrophy of cirri is typical for tong-stalked flexible pentacrinids.