Barreirinha Formation

The Barreirinha Formation is a late Frasnian geologic formation of the Amazon Basin in the state of Amazonas of northern Brazil. The group comprises deep marine black shales and sandstones.

Fossil content
The formation has provided conodont fossils of:


 * Mehlina gradata
 * Ozarkodina aff. sannemanni
 * Cryptotaxis sp.
 * Polygnathus sp.
 * ?Prioniodina sp.