Placerville Localities 7-10 (Permian of the United States)

Also known as San Miguel Canyon

Where: San Miguel County, Colorado (38.0° N, 108.0° W: paleocoordinates 8.7° N, 32.9° W)

• coordinate estimated from map

• small collection-level geographic resolution

When: Cutler Formation, Wolfcamp (296.4 - 268.0 Ma)

• about 550-620 feet below top of Cutler Fm.

•" [...] the present [...] study [...] has convinced us that the age is Early Permian beyond all reasonable doubt, equivalent to that of the Moran, Putnam, and Admiral Formations of Texas." (Lewis & Vaughn, 1965 p. C41). According to that statement the collection is of Wolfcampian age.

• group of beds-level stratigraphic resolution

Environment/lithology: fluvial-lacustrine; fine, micaceous, red siliciclastic sediments and lenticular, gray conglomerate

• No interpretation is given by the authors. The description of the rocks suggests that they represent a playa setting with periodically active alluvial fans.
• "In the Placerville area, the Cutler Formation is made up of interbedded, interlensing conglomerate, sandstone, siltstone, and shale. [...] The coarse clastic rock outcrops are generally a dark red to maroon, but they are gray to

•greenish gray in some places. [...] Crossbedding is common. Torrential deposition took place, as shown by lateral gradation, interlensing, and interbed

•ding between sandstone and conglomerate. No individual beds of conglomerate can be traced laterally for more than a few hundred feet. Finer grained micaceous sandstone, siltstone, and shale that weather to hematite red commonly contain bleached zones from 1 to 75 mm in diameter; these zones seemingly have organic centers. These finer clastics yielded almost all the fossil vertebrates; they contain many mud cracks and raindrop and other impressions including footprints." (Lewis & Vaughn, 1965 p. C5)

Size class: macrofossils

Reposited in the MCZ

Collection methods: bulk,

Primary reference: G. E. Lewis and P. P. Vaughn. 1965. Early Permian Vertebrates from the Cutler Formation of the Placerville Area, Colorado. United States Geological Survey Professional Papers 503-C:C1-C46 [J. Mueller/T. Liebrecht/T. Liebrecht]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 85479: authorized by Johannes Mueller, entered by Torsten Liebrecht on 29.12.2008

Creative Commons license: CC BY (attribution)

Taxonomic list

Osteichthyes
 Temnospondyli - Dissorophidae
Platyhystrix rugosus Case 1910 tetrapod
MCZ 2982
Reptilia
 Eureptilia - Captorhinidae
? Captorhinidae indet. Case 1911 eureptile
MCZ 2981
Osteichthyes
 Pelycosauria -
Pelycosauria sp. pelycosaur
MCZ unnumbered
 Cotylosauria -
Limnoscelops longifemur n. gen. n. sp.
Limnoscelops longifemur n. gen. n. sp. Lewis and Vaughn 1965 tetrapod
MCZ 2984 (type)
 Seymouriamorpha - Seymouriidae
Seymouria sp. Broili 1904 tetrapod
MCZ 2983; "new but unnamed species"