Triassic vertebrates of gondwanan aspect from the richmond basin of virginia.
نویسندگان
چکیده
A new locality of early Late Triassic age in the Richmond basin of east-central Virginia has yielded abundant remains of a diversified assemblage of small to medium-sized tetrapods that closely resembles Southern Hemisphere (Gondwanan) assemblages in the predominance of certain synapsids. Associated palynomorphs indicate an early middle Carnian age for the fossiliferous strata. The discovery suggests that previously recognized differences between tetrapod assemblages of early Late Triassic age from Gondwana and Laurasia at least in part reflect differences in stratigraphic age, rather than geographic separation.
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ورودعنوان ژورنال:
- Science
دوره 249 4972 شماره
صفحات -
تاریخ انتشار 1990