Coralinofaune of the Pirabas Formation (Lower Miocene), State of Pará: new taxa.

Abstract

This paper presents a systematic study of new coralinofaune elements of the Pirabas Formation. Trochoseris catadupensis, Discotrochus sp., Fungia (Cycloseris) costulata, Plascomilia sp., Bathycyathus sp., Asterosmilia compressa, Balanophyllia (Eupsammia) sp. And Dendrophyllia sp were recognized. This species are anermatypic, have affinity with the faunes that occur in Tertiary litostratigraphic units of the Central and South Americas, and are common in marine biotas since the Eocene. Asterosmilia compressa is an additional index fossil for the Pirabas Formation, because marks the Lower Miocene in Dominican Republic. The Fungia (Cycloseris) costulata, recorded as Recent in Asia, is present in the Pirabas Formation, south border of the Caribbean biogeographic realm, and represents the first record of the disjunct endemism or bipolarity, that occur in systematic groups whose biologic events of the rapid evolution and irradiation allow a species to occur in hemispheres separated by a distinct barriers, although in separated geologic times.