ASTEROCALCULUS HERAKI N. GEN., N. SP., A NEW CALCAREOUS ALGA (GYMNOCODIACEAE) FROM THE UPPER TRIASSIC HAUPTDOLOMITE OF ZUMBERAK, NORTH CROATIA

A sample of Upper Triassic, early diagenetic, peritidal dolomite (Haup tdolomite) from western Zumberak (north Croatia) contains a new specie s of calcareous algae (family Gymnocodiaceae). The new algal species i s accompanied by rich foraminiferal assemblage consisting of numerous Triasina hantkeni, Auloconus permodiscoides, and Aulo tortus sinuousus and less numerous Aulotortus friedli and A. tenuis. The new algal spe cies is represented by numerous variously oriented sections which enab le the accurate description and interpretation of its morphologic feat ures of both outer shape and inner structure. In the present paper the new algal species is described as Asterocalculus heraki n. gen., n. s p., characterized by a cylindrical thallus with loosely spaced levels of tubular protrusions, supposedly functioning as another type of repr oductive structures, in addition to 'conceptacles', or having some unk nown physiological function.