CABALERI nora Graciela
The angiosperm pollen Volkheimerites labyrinthus gen. et sp. nov. from the earliest Paleogene (Danian) of Patagonia, Argentina
NARVAEZ, P. L.; MEGO, N.; SILVA NIETO, D. G.; PRAMPARO, M.B.; CABALERI, N. G.
AMER ASSOC STRATIGRAPHIC PALYNOLOGISTS FOUNDATION
Lugar: Huston; Año: 2022 p. 1 - 13
Volkheimerites labyrinthus gen. et sp. nov., an angiosperm pollen type, is fully described and illustrated. The specimens were retrieved from lower Paleocene strata of the Salamanca Formation (San Jorge Basin) located in Chubut Province, Patagonia, Argentina. Medium to large size (25.555 lm) and a characteristic striate sculpture with labyrinthine pattern are distinguishing features of the grains in this new genus. Volkheimerites labyrinthus shares the presence of a coarse tectum supported by columellae with the fossil genera Dichastopollenites, Trisectoris and Periretisyncolpites, and some Winteraceae and Annonaceae species, but differs in having striate-labyrinthine as opposed to reticulate ornamentation. Our material is also distinguishable by the occurrence of solitary grains (monads) instead of the morefrequent presence of tetrads in the Winteraceae family or grains separated into two hemispheres as in Dichastopollenites. The large thin area of the exine appears to be morphologically analogous to the proximal thinning of the exine in the monads of tetrads as occurs in some Annonaceae species. The detailed description and illustration of this new angiosperm pollen genus expands our understanding of Paleocene plant diversity in Patagonia.