New paleobotanical data from the Puntudo Chico Formation (uppermost Cretaceous, Chubut Province, Argentina)

VERA, E.I.; PEREZ LOINAZE, V.S.; LLORENS, M.; PASSALIA, M.G.

Revista del Museo Argentino de Ciencias Naturales, n.s.

Museo Argentino de Ciencias Naturales Bernardino Rivadavia

Lugar: Buenos Aires; Año: 2023

1853-0400

The Puntudo Chico Formation is a continental unit cropping out in central and northern region of the Chubut Province in Argentina. It is one of the units that covers the Chubut Group, and its age is currently regarded as Campanian to lower Maastrichtian. The paleontological content of this unit essentially consist of silicified conifer trunks of Podocarpoxylon mazzoni (Petriella) Müller-Stoll et Schultze-Motel, Agathoxylon antarcticus (Poole et Cantrill) Pujana, Santillana et Marenssi and Brachyoxylon sp. cf. B. currumili Bodnar, Escapa, Cúneo et Gnaedinger 2013 (reported from the El Quiosco locality), and palms and the dicot Aextoxicoxylon kawasianus Vera, Perez Loinaze, Llorens et Passalia identified at Estancia María de las Nieves locality. In this contribution, new conifer woods are reported from the latter unit. Podocarpoxylon mazzoni is reported as the most abundant taxon in this site, as in El Quiosco. A second taxon is Cupressinoxylon austrocedroides Nishida, representing the first record of the genus for the unit. Finally, a third wood type is recognized, which can be separated from the other two taxa here identified, but given its deficient preservation remains with unclear taxonomic placement. The shared presence of P. mazzonii and C. austrocedroides in the Puntudo Chico Formation and in a Danian unit cropping out in the region (i.e. the Salamanca Formation) is discussed.