Novelties in the xylotaphoflora from Chiquimil Formation (Miocene), Catamarca-Argentina

摘要

The purpose of this study is to present two new records of angiosperm woods from Cerro Pampa locality in Catamarca province, Argentina. Chiquimil Formation, a fossiliferous unit composed of volcaniclastic sandstones with intercalated mudstones from the late Miocene, outcrops in this locality. Fabaceae Menendoxylon vasallensis Lutz and Paraalbizioxylon caccavarie Martinez woods have been formerly recorded in this fossiliferous site. In this work, the oldest record of Malvaceae for Argentina is presented and described: Bastardioxylon antiqua nov. gen. et sp. whose most distinctive feature is the presence of rays with sheath cells in the secondary wood. Furthermore, Menendoxylon lutzi nov. sp. has preserved a parenchymatic pith with the presence of arthropod coprolites and fungal filaments. These associated organisms provide useful information on the paleoenvironment that prevailed in the area and indicate warm and seasonally humid conditions which are ?in turn? sustained by the data derived from fossil biota and sedimentology. The two new angiosperm woods records from Cerro Pampa extend the composition and distribution of the paleoxyloflora components in Santa Maria Group.