ammonites
Rio Gualo (5th cycle) (Triassic of Argentina)

Where: La Rioja, Argentina (29.9° S, 67.8° W: paleocoordinates 49.5° S, 36.9° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Los Rastros Formation (Agua de la Peña Group), Ladinian (242.0 - 235.0 Ma)

• Insect remains are preferentially preserved in olive-green, thinly laminated mudstones deposited in deep, well-oxygenated lakes.

• formation-level stratigraphic resolution

Environment/lithology: lacustrine - large; lithified, black, carbonaceous claystone

• "The features observed in the facies assemblage A suggest that it was deposited in a deep off-shore lacustrine depositional environment. The claystones were deposited by suspension in distal-lake conditions…" Mancuso et al., 2007
• "This facies assemblage is dominated by dark gray to black carbonaceous claystones (Fl) interbedded with iron mudstones and very fine-grained sandstones (SFm) (figures 3, 4). The tabular beds form a laterally persistent succession with thickness that ranges from 2 to 5 m. The claystones are horizontally laminated, and formed by continuous microlamination with different grain sizes."

Size classes: macrofossils, mesofossils

• beetle specimens consist of 90% isolated elytra

Preservation: mold/impression

Collection methods: quarrying,

• Specimens kept in PULR-I – Invertebrate Paleontological Collection, Universidad Nacional de La Rioja, Argentina

Primary reference: R. G. Martins-Neto, O. F. Gallego, and R. N. Melchor. 2003. The Triassic insect fauna from South America (Argentina, Brazil and Chile): a checklist (except Blattoptera and Coleoptera) and descriptions of new taxa. Acta Zoologica Cracoviensia 46:229-256 [M. Clapham/J. Karr/M. Clapham] more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 122987: authorized by Matthew Clapham, entered by Jered Karr on 08.01.2012

Creative Commons license: CC BY-NC-ND (attribution-noncommercial-no derivatives)