Trigonia (Scabrotrigonia) emoryi (Conrad, 1857)

Remarks

• Collector:   Dan Milam

• Formation:  Washita Group, Lower Weno Limestone

• Location:    Tarrant County, TX

General Info

Synonyms (older names and misidentifications in the literature)

• "Cordova Clam"
• 1857 Trigonia emoryi Conrad
• 1903 Trigonia emoryi Conrad; Shattuck
• 1910 Trigonia emoryi Conrad; Böse
• 1924 Trigonia emoryi Conrad; Gillet
• 1928 Trigonia emoryi Conrad; Adkins
• 1944 Trigonia emoryi Conrad; Shimer and Shrock
• 1953 Trigonia emoryi Conrad; Brand
• 1960 Trigonia emoryi Conrad; Perkins
• 1969 Pterotrigonia (Scabrotrigonia) emoryi (Conrad); Moore
• 1977 Scabrotrigonia emoryi (Conrad); Kauffman
• 1982 Pterotrigonia emoryi (Conrad); Offeman et al.
• 2002 Scabrotrigonia emoryi (Conrad); Akers & Akers

Stratigraphic Occurrence

• Uppermost Washita Group, Grayson Formation of north Texas
• Uppermost Washita Group, Buda Formation of central Texas
• Fredericksburg and Washita Group equivs in Coahuila and Chihuahua, Mexico
• Upper Washita Group, Mainstreet Formation of north Texas
• Upper Washita Group, Weno Formation of north Texas
• Lower Washita Group, Fort Worth Formation of north Texas
• Fredericksburg Group, Goodland Formation of north Texas
• Fredericksburg Group, Walnut Formation of north Texas

Age

• Trigonia (Scabrotrigonia) emoryi (Conrad) is a long–ranging clam. It ranges from about late Middle Albian to lower Cenomanian time (~104 to 97 mya).

Geographic Occurrence (by no means an all-inclusive list)

• Chihuahua, Mexico
• Coahuila, Mexico
• El Paso County, Texas
• Tarrant County, Texas
• Travis County, Texas
• Wise County, Texas

Remarks

         For identification and descriptions, see:

• Böse, E. 1910. Monografía Geológica y Paleontológica del Cerro de Muleros, Cerca de Ciudad Juárez, Estado de Chihuahua. Boletín del Instituto Geológico de México 25.
• Perkins, B. F. 1960. Biostratigraphic Studies in the Comanche (Cretaceous) Series of Northern Mexico and Texas. Geological Society of America Memoir 83.