MACNBR   00242
MUSEO ARGENTINO DE CIENCIAS NATURALES "BERNARDINO RIVADAVIA"
Unidad Ejecutora - UE
artículos
Título:
Taxonomy and biostratigraphy of Cretaceous megaspores from Patagonia, Argentina
Autor/es:
LILIANA VILLAR DE SEOANE AND SERGIO ARCHANGELSKY
Revista:
CRETACEOUS RESEARCH (PRINT)
Editorial:
Elsevier Science Ltd29(2):354-372.
Referencias:
Lugar: Inglaterra; Año: 2008 vol. 29 p. 354 - 374
ISSN:
0195-6671
Resumen:
Abstract. Megaspores from the Kachaike and Piedra Clavada formations of Albian and
?Cenomanian age in Santa Cruz Province, Argentina, are described and
illustrated by scanning electron micrographs. These include six new species:
Arcellites humilis, A. pentagonalis, A. sp. A, Erlansonisporites verrucatus,
Minerisporites aequatus and Striatriletes areolatus. Striatriletes reticulatus
(Zerndt) Sweet and Trileites cf. T. murrayi
(Harris)
Marcinkiewicz are recorded for the first time from Argentina. Another eight
species that were previously recorded in Patagonia are also described based on
specimens found in new localities. Comparison with similar megaspore taxa from
other palaeofloristic regions suggests that the megaspores in these formations
are of Albian age (perhaps extending into the Cenomanian), confirming previous
data obtained from
other
studies of marine and terrestrial fossils from these formations. The botanical
affinities of the megaspores with heterosporous lycopsids (Isoetaceae and
Selaginellaceae) and water ferns (Marsileaceae and Salviniaceae) suggest that a
warm, humid climate and abundant water bodies prevailed during the Albian in
Patagonia. The stratigraphic distribution of all known Early Cretaceous
Patagonian megaspores allows recognition of three separate assemblages, M1eM3,
each characterized by several exclusive taxa. M1 spans the
BerriasianeBarremian, M2 is Aptian, and M3 is Albiane?Cenomanian.