Bennettitales from the Middle Jurassic of northwestern Oaxaca, Mexico: Diversity, sedimentary environments, and phytogeography
Por:
Lozano-Carmona D.E., Velasco-De León M.P.
Publicada:
1 oct 2021
Resumen:
The Jurassic flora of Mexico represents a key element for the knowledge
of the paleoflora on the western margin of equatorial Pangea because of
its abundance and diversity. Bennettitales were the dominant group and
are represented by leaves and reproductive organs in Jurassic outcrops
from southern Mexico. This group has been historically recorded in seven
lithostratigraphic units in southern Mexico in a range from the Toarcian
to the Callovian. These reports have focused on morphological and
taxonomical aspects for the obtention of paleofloristic listings by
locality but do not provide environmental data or have any impact on
biostratigraphic or phytogeographic analyses. The highest number of
localities in Mexico has been reported in the state of Oaxaca, where
plant fossils are more abundant and better preserved in comparison with
localities of Guerrero, Puebla, Veracruz, and Hidalgo states. Therefore,
in order to reinforce the paleofloristic knowledge of southern Mexico,
the present study documents the diversity of Bennettitales in
northwestern Oaxaca region, which is composed of 11 fossil-genera and 41
fossil-taxa, included 30 valid species and 11 species that need
taxonomic revision. We provide the description of a new species,
Williamsonia sanjuanensis sp. nov., new findings of Williamsonia
nathorstii, and the first record of Bennetticarpus for southern Mexico.
We also describe fossiliferous outcrops of the Zorrillo and
Zorrillo/Taberna undifferentiated formations and propose their
sedimentary environments. In addition, we provide a proposal of one
biozone based on Bennettitales. Finally, we recognize six
spatio-temporal distribution patterns for this plant group in
northwestern Oaxaca. These new data add to a growing set of information
on the Jurassic flora of Mexico and allow to substantiate the
paleobotanic importance of southern Mexico within the region of North
America.
Filiaciones:
Lozano-Carmona D.E.:
Posgrado en Ciencias Biológicas, Unidad de Posgrado, Circuito de Posgrados, Ciudad Universitaria, Universidad Nacional Autónoma de México, Coyoacán, Ciudad de México, C.P 04510, Mexico
Colección de Paleontología, Facultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México, Batalla 5 de Mayo, Ejercito de Oriente, Iztapalapa, Ciudad de México, C.P 09230, Mexico
Velasco-De León M.P.:
Colección de Paleontología, Facultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México, Batalla 5 de Mayo, Ejercito de Oriente, Iztapalapa, Ciudad de México, C.P 09230, Mexico
Lozano-Carmona, DE (Corresponding Author), Univ Nacl Autonoma Mexico, Posgrad Ciencias Biol, Unidad Posgrad, Circuito Posgrad, Ciudad Univ, Ciudad De Mexico 04510, Mexico. Enrique Lozano-Carmona, Diego, Univ Nacl Autonoma Mexico, Posgrad Ciencias Biol, Unidad Posgrad, Circuito Posgrad, Ciudad Univ, Ciudad De Mexico 04510, Mexico. Enrique Lozano-Carmona, Diego
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