title: A Cretaceous scleractinian coral with a calcitic skeleton.
abstract: It has been generally thought that scleractinian corals form purely aragonitic skeletons. We show that a well-preserved fossil coral, Coelosmilia sp. from the Upper Cretaceous (about 70 million years ago), has preserved skeletal structural features identical to those observed in present-day scleractinians. However, the skeleton of Coelosmilia sp. is entirely calcitic. Its fine-scale structure and chemistry indicate that the calcite is primary and did not form from the diagenetic alteration of aragonite. This result implies that corals, like other groups of marine, calcium carbonate-producing organisms, can form skeletons of different carbonate polymorphs.
authors.affiliation: Institute of Paleobiology, Polish Academy of Sciences, Twarda 51/55, PL-00-818 Warsaw, Poland. stolacy@twarda.pan.pl
authors.forename: Jaroslaw
authors.initials: J
authors.lastname: Stolarski
authors.forename: Anders
authors.initials: A
authors.lastname: Meibom
authors.forename: Radoslaw
authors.initials: R
authors.lastname: Przenioslo
authors.forename: Maciej
authors.initials: M
authors.lastname: Mazur
mesh_terms: D000818:Animals; D037421:Anthozoa / Q000033:anatomy & histology* / Q000737:chemistry*; D002113:Calcification, Physiologic; D002119:Calcium Carbonate; D003460:Crystallization; D005580:Fossils; D019015:Geologic Sediments; D014131:Trace Elements / Q000032:analysis
chemical_list: D014131:Trace Elements; D002119:Calcium Carbonate