Pliensbachian corals from the Western Tethys

Abstract

ABSTRACT Late Liassic in the Western Tethys has been the cradle of Middle and Late Jurassic diversity of corals. This is what revised and enhanced taxonomy of corals from Pliensbachian and Toarcian stages reveals. The current new taxonomic study of Pliensbachian corals describes 66 species distributed in 41 genera and 20 identified families. It includes four new genera: Podosmilia n. gen., Tubulosmilia n. gen., Prismastrea n. gen. and Spongiocoenia n. gen.; and 20 new species: Axosmilia amellagouensis n. sp., Apocladophyllia guigouensis n. sp., Coryphyllia bicuneiformis n. sp., Coryphyllia capillaria n. sp., Proleptophyllia calix n. sp., Proleptophyllia magna n. sp., Proleptophyllia subphaceloida n. sp., Fungiaphyllia praecursor n. sp., F. rotunda n. sp., Margarosmilia dividenda n. sp., Paravolzeia calabrensis n. sp., Distichophyllia pauciseptata n. sp., Retiophyllia zizensis n. sp., Epismiliopsis paraeudesi n. sp., Phacelostylophyllum mg. arbustulum n. sp., Podosmilia horologium n. gen., n. sp., Stylophyllopsis bovista n. sp., S. veracolumella n. sp., Tubulosmilia regularis n. gen., n. sp. and Prismastrea organum n. gen., n. sp. So many new species appear surprising at first sight considering the special attention paid in this study to the correction of species diversity overestimations that took place in the literature of the last century as a consequence of a typological approach. Many taxa previously considered extinct at T-J boundary were still living during Pliensbachian times, various genera are known only for Pliensbachian. In addition, a small number of genera namely Isastrea, Montlivaltia and Thamnasteria have their first occurrence during this stage. Despite their low abundance during Pliensbachian, these genera will significantly increase their part in Middle and Upper Jurassic communities. Most collected coral assemblages come from both reefs and level-bottom assemblages found in carbonate platform situation.