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Cedar Hill, TMM 43209 (Cretaceous of the United States)

Where: Dallas County, Texas (32.6° N, 97.0° W: paleocoordinates 33.0° N, 64.3° W)

• coordinate based on nearby landmark

• small collection-level geographic resolution

When: Collignoniceras woollgari ammonoid zone, Kamp Ranch Limestone Formation, Middle Turonian (94.3 - 89.3 Ma)

• "...less than 20 cm above the Turonian Kamp Ranch limestone, which lies in the Collignoceras woollgari Zone. The ten metres overlying the Kamp Ranch have no reported ammonites and the Prionocyclus percarinatus Zone is not recorded... we consider that the postition of [the] type approximates the Collignoceras woollgari Zone... the absolute age is constrained by the underlying Vasoceras birchbyi Zone (93.40 +or- 0.63) and the overlying Prionocyclus percarinatus Zone (90.51 +or-0.45, each separated from the Collignoceras woollgari Zone by one missing zone. an estimate of ~92 Ma for the first appearance of these primitive mosasauroids is not unreasonable" (Jacobs et al. 2005, p. 262).

• formation-level stratigraphic resolution

Environment/lithology: limestone

Size class: macrofossils

Reposited in the TMM

Primary reference: G. L. Bell and M. J. Polcyn. 2005. Dallasaurus turneri, a new primitive mosasauroid from the Middle Turonian of Texas and comments on the phylogeny of Mosasauridae (Squamata). Netherlands Journal of Geosciences 84(3):177-194 [M. Uhen/M. Uhen] more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 80888: authorized by Mark Uhen, entered by Mark Uhen on 19.05.2008

Creative Commons license: CC BY (attribution)