OSTEODERMS OF JUVENILES OF STAGONOLEPIS (ARCHOSAURIA: AETOSAURIA) FROM THE LOWER CHINLE GROUp, EAST-CENTRAL ARIZONA
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چکیده
We describe for the first time small «25 mm) dorsal paramedian, lateral, and appendicular /ventral scutes (osteoderms) of aetosaurs from the Blue Hills in Apache County, east-central Arizona. These diminutive scutes, collected by c.L. Camp in the 1920s, preserve diagnostic features of the common Adamanian aetosaur Stagonolepis. Stagonolepis wellesi was already known from the Blue Hills, so identification of juvenile scutes of Stagonolepis simply confirms the existing biostratigraphic and paleogeographic distribution of the genus. Still, application of the same taxonomic principles used to identify larger, presumably adult, aetosaur scutes suggests that juvenile aetosaurs should provide the same level of biostratigraphic resolution obtained from adults.
منابع مشابه
Redescription of Calyptosuchus (Stagonolepis) wellesi (Archosauria: Pseudosuchia: Aetosauria) from the Late Triassic of the Southwestern United States with a discussion of genera in vertebrate paleontology
Calyptosuchus wellesi is a medium-sized desmatosuchian aetosaur common in Adamanian (early to middle Norian) age rocks from the Chinle Formation and Dockum Group of the Western United States. Known chiefly from osteoderms, this taxon has never been fully described and non-osteoderm material assigned to Calyptosuchus has been done so based on questionable criteria. Mapping of aetosaurian element...
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