Aratrisporites compositus n. sp., a guide-fossil from the Triassic Cuyo Basin, western Argentina

VOLKHEIMER, W. & ZAVATTIERI, A.M.

NEUES JAHRBUCH FUR GEOLOGIE UND PALAONTOLOGIE-MONATSHEFTE

E. Schweizerbart'sche Verlagsbuchhandlung

Lugar: Stuttgart; Año: 1991 vol. 9 p. 564 - 578

0028-3630

The morphologic features and intraspecific variability of a relevant population of a new species of Aratrisporites (monolete spores) from the material of Middle to Upper Triassic age (Potrerillos Formation, Cuyo Basin, Mendoza Province, Argentina) are studied. Statistic counts of suprageneric groups indicate a moist paleoenvironment. The species is compared with other selected species registered previously in gondwanic and extra-gondwanic sedimenta of the world. An evolutionary line from Aratrisporites tenuispinosus to A. compositus is proposed. At the present state of knowledge, the distribution of A. compositus is limited to the Middle to Upper Triassic of southern South America.