Weches L2: Marquez, Leon County, TX (Eocene of the United States)

Where: Leon County, Texas (31.2° N, 96.3° W: paleocoordinates 33.3° N, 85.2° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Weches Formation (Claiborne Group), Lutetian (47.8 - 41.3 Ma)

• Original Description: Middle Eocene: Claiborne Group: Mount Selman Formation: Weches Member. (Revised stratigraphy elevates the Weches member to formation in the Lutetian).

• group of beds-level stratigraphic resolution

Environment/lithology: marine; concretionary, brown, gray marl

• (The Weches localities are all similar, so a generalized section is provided here). Weches member of Mount Selman formation - g. Red, weathered, glauconitic, fossiliferous marls... 10-20 ft., f. Grey to brown limestone forming large rounded concretions, discontinuous. Corresponds to lentil B of Renick and Stenzel (12, p. 79) in counties further west... 1 ft. e. Layer of Ostrea sellaeformis Conrad and Venericardia planicosta Lamarck... 1 ft. d. Grey to brown, powdery marls with white calcareous nodules, frequently covered with slumped materials... 5 ft. c. Grey, roughly pitted limestone forming prominent benches. Corresponds to lentil A of Renick and Stenzel (12, p.79) in counties further west... 1-2 ft. b. Red-brown, weathered, glauconitic sands and marls with Ostrea sellaeformis Conrad... 1 ft. Queen City member of Mount Selman formation - a. Grey-brown, silty, lignitic shales. (Beds b to d form the basal part of the Weches member, which makes a steep scarp in this region. Zanthopsis peytoni in its typical form is restricted to bed d and occurs in rough nodular lime concretions, the variety parva is restricted to bed g and occurs free. Both forms are common enough to be used as guide fossils for their respective levels).

Size class: macrofossils

Preservation: concretion

Collection methods: Other fossils were collected during this investigation, but only crustaceans are presented here.

Primary reference: H. B. Stenzel. 1934. Decapod Crustaceans from the Middle Eocene of Texas. Journal of Paleontology 8(1):38-56 [L. Ivany/C. Visaggi/C. Visaggi]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 43138: authorized by Linda Ivany, entered by Christy Visaggi on 10.08.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

Malacostraca
 Decapoda - Callianassidae
Callianassa wechesensis n. sp. Stenzel 1934 decapod
 Decapoda - Zanthopsidae
Zanthopsis peytoni Stenzel 1934 crab