La Pola, Argentine Bryozoans (Ordovician of Argentina)

Where: San Juan, Argentina (30.3° S, 68.5° W: paleocoordinates 34.7° S, 133.7° W)

• coordinate stated in text

When: Amorphognathus tvaerensis brachiopod zone, La Pola Formation, Sandbian (458.4 - 453.0 Ma)

• included in Las Plantas sequence; Baltoniodus variabilis Subzone

Environment/lithology: shallow subtidal; sandstone

• conclusions: combination of these growth forms indicates shallow shelf conditions
• fig. 3: Microfacies of the main bryozoan-bearing rocks (lenticular quartz-bioclastic-rich sandstones

•figure 2: silty green shales/fine grained sandstone, bioclastic conglomerates and breccias, pebbly mudstones, bioturbated and nodular mudstones

•succession of thick-bedded coarse-grained debris flows (ranging from mud to clast supported) with interbedded pebbly mudstones, amalgamated lenticular quartz-bioclastic- rich sandstones, as well as a few turbidites and silty shales

Size classes: macrofossils, mesofossils

Primary reference: A. Ernst and M. Carrera. 2022. A cool-water bryozoan association from the La Pola Formation (Sandbian, Ordovician) of Argentine Precordillera. Geodiversitas 44(20):563-601 [B. Seuss/B. Seuss]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 226179: authorized by Barbara Seuss, entered by Barbara Seuss on 21.06.2022

Creative Commons license: CC BY (attribution)

Taxonomic list

Crinoidea indet. Miller 1821 Sea lily
 Trepostomata - Heterotrypidae
 Trepostomata - Halloporidae
 Trepostomida -
 Trepostomida - Monticuliporidae
 Trepostomida -
 Fenestrata - Chasmatoporidae
Parachasmatopora "sp. A" Morozova and Lavrentjeva 1981
 Cystoporata - Constellariidae
 Cryptostomata - Arthrostylidae
Arthroclema "sp. A" Billings 1862
 Cryptostomata -
 Cryptostomata - Rhinidictyidae
 Cryptostomata - Stictoporellidae