FIRST RECORD OF VOLTZIALEAN MALE CONE (LUTANTHUS) AND PODOCARPACEAN FEMALE CONE (RISSIKISTROBUS) FROM THE LATE TRIASSIC OF ARGENTINA, INCLUDING NEW PLANT REMAINS OF THE PASO FLORES FORMATION

A.M. ZAVATTIERI; GNAEDINGER SILVIA

AMEGHINIANA

ASOCIACION PALEONTOLOGICA ARGENTINA

Lugar: Buenos Aires; Año: 2017 vol. 54 p. 224 - 246

0002-7014

New plant remains from the upper section of the Paso Flores Formation, at the Cañadón de Pancho locality, western area of the Collón Curá River, Neuquén Province, Argentina are described and illustrated. These are: Lutanthus ornatus, Rissikistrobus plenus, Rissikistrobus reductus, Rissikia media, Umkomasia sp., Sphenobaiera argentinae, Pseudoctenis spatulata, Taeniopteris crassinervis, and Yabeiella brackebuschiana. In addition, Baiera triassica Gnaedinger and Zavattieri, replacing the homonymous species previously identified in Argentina as Baiera taeniata, Ginkgo taeniata, Sphenobaiera taeniata, is herein described. Furthermore, species previously described for other localities in the Paso Flores Formation are recorded for the first time for the Quemquemtreu area at Cañadón Pancho locality. These species are: Asterotheca rigbyana, Marattiopsis muensteri, Cladophlebis kurtzii, C. indica, Dictyophyllum (Dictyophyllum) tenuifolium, Goeppertella stipanicicii, Dicroidium incisum, D. odontopteroides, D. lancifolium, Pachydermophyllum praecordillerae, Heidiphyllum elongatum, Baiera furcata, Sphenobaiera robusta, Pseudoctenis carteriana and P. falconeriana. The Voltziales male cone Lutanthus herein described from the Paso Flores Formation is the second record for the Gondwana realm; the Podocarpaceae female cone Rissikistrobus is reported for the first time from Triassic strata of Argentina and constitutes the third record for Gondwana. Comparisons with the plant diversity recorded in other localities of the Paso Flores Formation throughout the Neuquén Province are also analyzed. The Cañadón de Pancho mega and microflora assemblages suggest a Late Triassic (Uppermost Norian = Rhaetian) age, being the youngest fossil flora recorded to date in the Triassic basins of Argentina.