MSM 00-103, between Winslow and Holbrook (Triassic to of the United States)

Also known as Moenkopi

Where: Navajo County, Arizona (35.0° N, 110.7° W: paleocoordinates 3.5° N, 39.1° W)

• coordinate estimated from map

• small collection-level geographic resolution

When: Holbrook Member (Moenkopi Formation), Aegean to Aegean (247.2 - 242.0 Ma)

• Early Anisian age is based on stratigraphic position and taxonomic correlations, e.g. Eocyclotosaurus Ortlam 1970 in the Holbrook Member with E. lehmanni in the Upper Buntsandstein, Germany. Age is also supported by magnetostratigraphy and Eocyclotosaurus wellesi (Lucas and Schoch 2002).

•The Holbrook Member is bounded below by the uppermost gypsum layer at the Moqui Member contact, an is separated by the overlying Chinle Formation by an unconformity.

• bed-level stratigraphic resolution

Environment/lithology: terrestrial; lag, fine-grained, pebbly conglomerate

• ridge-forming channel lag deposits consisting of small pebbles and rip-up clasts.

Size class: macrofossils

Collection methods: surface (float), mechanical,

• MSM - Mesa Southwest Museum, Mesa, AZ

Primary reference: S. J. Nesbitt and R. L. Whatley. 2004. The first discovery of a rhynchosaur from the upper Moenkopi Formation (Middle Triassic) of northern Arizona. PaleoBios 24(3):1-10 [R. Whatley/R. Whatley/R. Whatley]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 49856: authorized by Robin Whatley, entered by Robin Whatley on 28.04.2005, edited by Richard Butler

Creative Commons license: CC BY (attribution)

Taxonomic list

• Hybodonts, temnospondyls, poposaurids, vertebrate coprolites, and Neocalamites impressions are said to be found in similar channel lag deposits within the Holbrook member.
Osteichthyes
 Dicynodontia -
Dicynodontia indet. dicynodont
MSM 3310, isolated tusk
Reptilia
 Rhynchosauria - Rhynchosauridae
Ammorhynchus navajoi Nesbitt and Whatley 2004 rhynchosaur
partial maxilla