Guichón (water well) (Cretaceous to of Uruguay)

Also known as Uruguaysuchus aznarezi type

Where: Paysandù, Uruguay (32.3° S, 57.2° W: paleocoordinates 38.8° S, 29.4° W)

• coordinate based on nearby landmark

• small collection-level geographic resolution

When: Guichón Formation (Paysandú Group), Aptian to Aptian (125.0 - 83.6 Ma)

• See discussion in Soto et al. (2011, 2012) regarding the age of the Guichón Formation

• bed-level stratigraphic resolution

Environment/lithology: fluvial; sandstone

• These lithologies were deposited in southwest- trending alluvial–fluvial systems comprising low-sinuosity channels traversing through sandy plains. Subordinate to the already mentioned sandstones are conglomeratic and pelitic lithologies, interpreted as channel-fill and overbank deposits, respectively. It is inferred that the Guichón Formation was deposited in warm, semi-arid climatic conditions.
• Guichón Formation comprises mainly pink-greyish to reddish sandstones, which contain moderate to well-sorted, subrounded, fine to medium-sized grains in a pelitic matrix. These sandstones (which compositionally are feldspathic wackes) are either massive or may instead exhibit parallel lamination, cross-lamination and graded bedding.

Size classes: macrofossils, mesofossils

Collected by C. Rusconi in the 1930s

Collection methods: salvage, quarrying, mechanical,

Primary reference: F. v. Huene. 1934. Neue Saurier-Zähne aus der Kreide von Uruguay [New saurian teeth from the Cretaceous of Uruguay]. Centralblatt für Mineralogie, Geologie und Paläontologie, Abteilung B: Geologie und Paläontologie 1934(4):183-189 [M. Carrano/M. Carrano]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 65322: authorized by Matthew Carrano, entered by Matthew Carrano on 21.09.2006, edited by Philip Mannion

Creative Commons license: CC BY (attribution)

Taxonomic list

Reptilia
 Saurischia -
Theropoda indet.2 Marsh 1881 theropod
tooth "B"
 Neornithischia -
Iguanodontia indet.2 Baur 1891 bird foot dinosaur
tooth "A2"
Iguanodontia indet.2 Baur 1891 bird foot dinosaur
tooth "A1"
 Loricata - Uruguaysuchidae
"Uruguaysuchus aznarezi n. gen. n. sp." = Uruguaysuchus aznarezi1, "Uruguaysuchus terrai n. sp." = Uruguaysuchus aznarezi1
"Uruguaysuchus aznarezi n. gen. n. sp." = Uruguaysuchus aznarezi1 Rusconi 1933 crocodilian
CA unnumbered - holotype (an approximately.1.2-m-long articulated adult individual (including a complete skull, mandible, right forelimb, 18 vertebrae, both ilia and partial right hindlimb, as well as a few associated osteoderms); 5 partial paratype skeletons also found, but now lost (Soto et al. 2011); FC-DPV 2320 - referred specimen (partial skull, a lower jaw and three cervical vertebrae)
"Uruguaysuchus terrai n. sp." = Uruguaysuchus aznarezi1 Rusconi 1933 crocodilian
CA unnumbered - type (a complete mandible and skull in articulation)