Moenkopia

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Moenkopia
Temporal range: Middle Triassic, 247.2–242.0  Ma
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Moenkopia

Schaeffer & Gregory, 1961
Binomial name
Moenkopia wellesi
Schaeffer & Gregory, 1961

Moenkopia (meaning "for Moenkopi") is an extinct genus of prehistoric sarcopterygians from the Coelacanthidae [1] found in the Middle Triassic Moenkopi Formation of Arizona. The type, and only species, M. wellesi, was named in 1961 in honour of Samuel Paul Welles. [2] It is only known from the holotype, UMCP 36193, a partial skull consisting only of the basisphenoid that was collected in 1939 or 1940 by Samuel Welles and briefly noted on by him in 1947, [3] and other assorted specimens found before 2005 in the Radar Mesa by S. J. Nesbitt, W. G. Parker and R. B. Irmis. [4]

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Moenkopi Formation

The Moenkopi Formation is a geological formation that is spread across the U.S. states of New Mexico, northern Arizona, Nevada, southeastern California, eastern Utah and western Colorado. This unit is considered to be a group in Arizona. Part of the Colorado Plateau and Basin and Range, this red sandstone was laid down in the Lower Triassic and possibly part of the Middle Triassic, around 240 million years ago.

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References

  1. P. L. Forey. 1998. History of the Coelacanth Fishes 1-440
  2. B. Schaeffer and J. T. Gregory. 1961. Coelacanth fishes from the continental Triassic of the western United States. American Museum Novitates 2036:1-18
  3. S. P. Welles. 1947. Vertebrates from the Upper Moenkopi Formation of northern Arizona. University of California Publications in Geological Sciences 27(7):241-294
  4. S. J. Nesbitt. 2005. The Moenkopi Formation along the Little Colorado River in eastern Arizona. In S. J. Nesbitt, W. G. Parker, R. B. Irmis (eds.), Guidebook to the Triassic Formations of the Colorado Plateau in northern Arizona, Mesa Southwest Museum Bulletin 9:13-23