Morphology, taxonomy and distribution of the Early Cretaceous coral genus Holocoenia (Scleractinia) and its first record in the Caribbean

Abstract

Although ten species are currently assigned to the Early Cretaceous coral genus Holocoenia, its characteristics are poorly known. Using material from the type locality of the type species Astrea micrantha along with described and undescribed material from France, Mexico, Poland and Spain, the genus is revised. It has a cerioid form with small calices, compact septa, a styliform columella, and an incomplete septothecal to synapticulothecal wall. Provisionally, it is assigned to the family Thamnasteriidae, being closely related to Mesomorpha and Thamnasteria. The genera Stereocaenia and Paretallonia are considered junior synonyms of Holocoenia. According to the present revision the genus contains only two species, which range from the Valanginian to the Aptian. Holocoenia micrantha is restricted to the central Tethys whereas Holocoenia jaccardi extends geographically from South America (Aptian of Argentina) and southern North America (Aptian of Puebla, Mexico) to the eastern Tethys (Hauterivian of Georgia). The indication of the genus in the San Juan Raya area in Puebla is the fi rst indication in Central America. While the genus has been indicated in only eleven outcrop areas, making it rather rare, in many of these localities samples of Holocoenia are common.