DISTRIBUZIONE DELLE DASICLADALI (ALGHE VERDI) NEI SEDIMENTI DEL CRETACEO INFERIORE IN FACIES DI PIATTAFORMA CARBONATICA DELL'APPENNINO CENTRO-MERIDIONALE (LAZIO E ABRUZZO)

Abstract

Further micropaleontologic and biostratigraphic researches previously curried out on carbonatic Cretaceous sediments outcropping in Southern Lazio (M. Aurunci) and Abruzzi (M. d'Ocre), allowed us to identify a rich dasy­cladaleans association, particularly during Valanginian-Al­bian time interval. 25 species of dasycladaleans have been identify; severa! species such as Cylindroporella ivanovici (SOKAC), Cylin­droporella elliptica BAKALOVA, Salpingoporella hasi CoNRAD, RADOICié & REY, Clypeina radici SoKAC, are for the first time recorded in Italy. Local stratigraphic range of identified dasycladaleans is given (see Fig. 3); the taxon range has been referred to the previously established biozones (CmoccHINI & MANCINELLI, 1977; CHIOCCHINI, MANCINELLI & ROMANO, 1983). This range­chart shows that, during Upper Hauterivian-Lower Aptian time interval, a fluorishing of Algal species which appear var­ious and aboundant, is observed. At the end of Lower Apti­an the distribution of dasycladaleans has been interrupted un­til the end of lower Albian.