Los Alamitos vertebrates, lower section (Cretaceous to of Argentina)

Where: Río Negro, Argentina (42.1° S, 66.3° W: paleocoordinates 45.0° S, 52.3° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Los Alamitos Formation, Campanian to Campanian (83.6 - 66.0 Ma)

• lower section of formation includes two layers with fossils, about 7 meters apart, in lower third of section

• group of beds-level stratigraphic resolution

Environment/lithology: lacustrine - large; bioturbated siltstone

• dominant environment lacustrine, more brackish than fresh (clay flocculation in pelites). waters were oxygenated; lake permanent and shallow.
• "Pelitic facies: includes dominant massive, laminated or rippled (rare) siltstones and claystones, with yellowish (lower part of the sequences) to reddish, orange, brown and purple hues (upper part), and massive sandstones. This rocks show typical paquidermis solution pattern which allow its recognition in outcrops. The non-calcareous pelites contains (lower half) almost all the vertebrate remains"

Size classes: macrofossils, mesofossils

Preservation: trace

Collected by J. F. Bonaparte, J. E. Powell in 1982

Collection methods: quarrying, surface (float), surface (in situ), mechanical,

Primary reference: R. R. Andreis. 1987. The Late Cretaceous fauna of Los Alamitos, Patagonia, Argentina part I—stratigraphy and paleontology. Revista del Museo Argentina de Ciencias Naturales "Bernardino Rivadavia" e Instituto Nacional de Investigacion de las Ciencias Naturales: Paleontología 3(3):103-110 [M. Carrano/M. Carrano/M. Carrano]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 45088: authorized by Matthew Carrano, entered by Matthew Carrano on 04.10.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

 Saurischia - Titanosauridae
Titanosauridae indet.2 Lydekker 1885 titanosaurid
 Neornithischia - Hadrosauridae
"Kritosaurus australis" = Secernosaurus koerneri1
"Kritosaurus australis" = Secernosaurus koerneri1 Brett-Surman 1979 hadrosaurine