The regeneration in some caryophyllid corals from the Korytnica Clays (Middle Miocene;

Abstract

A common case of regeneration from very small fragments (composed even of those containing at least one entoseptum) is reported in some scleractinian corals coming from a specific, solitary-coral-dominated community of the near-to-shore facies of the Korytnica Clays (Middle Miocene, Badenian; Holy Cross Mountains, Central Poland). It concerns the specifically indeterminable caryophyllids, some individuals of which underwent regeneration twice. The regeneration itself (growth from tiny fragments of the primary individual) is discussed in its relation to the reparation (a repair of an injury within the animal's skeleton). The whole population of the regenerated caryophyIlids, which dominated a local near-to-shore community within, the Korytnica Basin, characterizes by the size distinctly smaller than that of normal individuals. This event is compared to that recognized in some populations of the present-day and ancient free-living bryozoans, those inhabiting the Korytnica Basin including. In both these groups (caryophyllid corals, and free-living bryozoans) the regeneration is discussed as an important mean for reproduction of the species, and as an immanent biological feature of some selected taxa.