Abstract

PUEBLA, Gabriela G. A new angiosperm leaf morphotype from the Early Cretaceous (Late Aptian) of San Luis Basin, Argentina. Ameghiniana [online]. 2009, vol.46, n.3, pp.557-566. ISSN 1851-8044.

A new fossil angiosperm leaf morphotype, "LC-Microphyll trifoliate", from the Late Aptian La Cantera Formation, central western Argentina, is described. The leaf remains occurred at the type section of the formation within a low diversity macrofloral association. Fossils are found mainly as isolated small size leaflets (0.3-1.5 cm long). The leaves are pinnately compound (imparipinnate, trifoliate), the leaflets have pinnately lobed margin, first vein category pinnate, secondary veins craspedodromous opposite to subopposite ending at the apex of lobes and an intramarginal vein. "LC-Microphyll trifoliate" is among the earliest record of leaf remains possibly allied to the eudicots and one of the first evidence of angiosperm with compound leaves.

Keywords : Angiosperm; Eudicots; Late Aptian; La Cantera Formation; Argentina.