Anzaldo Formation

Anzaldo Formation
Stratigraphic range: Katian ~460–446  Ma PreꞒ Ꞓ O S D C P T J K Pg N
Type	Geological formation
Unit of	Cochabamba Group
Underlies	San Benito Formation
Overlies	Capinota Formation
Lithology
Primary	Sandstone
Location
Coordinates	17°48′S65°48′W / 17.8°S 65.8°W / -17.8; -65.8
Approximate paleocoordinates	45°06′S127°30′W / 45.1°S 127.5°W / -45.1; -127.5
Region	Cochabamba Department
Country	Bolivia
Extent	Cordillera Oriental
Anzaldo Formation (Bolivia)

The Anzaldo Formation is a Katian geologic formation of central Bolivia. The formation belongs to the Cochabamba Group, overlies the Capinota Formation and is overlain by the San Benito Formation. The formation is famous for being where Sacabambaspis , a jawless fish that has become a popular internet meme in recent years, was discovered. ^[1]

Fossil content

The formation has provided the following fossils:

Fish

Pteraspidomorphi

• Huemacaspis bistrami ^[2]
• Sacabambaspis janvieri ^{[3] [4]}

Trilobites

• Leiostegina inexpectans ^[5]

Bivalves

• ?Grammysia sp. ^[5]
• ?Modiomorpha sp. ^[5]
• ?Parallelodon sp. ^[5]
• "Ctenodonta" sp. ^[5]
• "Goniophorina" sp. ^[5]

Gastropods

• Gyrospira tourteloti ^[5]

Lingulida

• Bistramia elegans ^[3]
• Dignomia munsterii ^{[2] [3]}

See also

• List of fossiliferous stratigraphic units in Bolivia
• Cancañiri Formation
• La Ciénega Formation
• Santiago Formation

References

1. Anzaldo Formation at Fossilworks.org
2. Emig & Herrera, 2006
3. Gagnier et al., 1996
4. Pradel et al., 2007
5. Branisa, 1965

Bibliography

• Pradel, A.; Sansom, I. J.; Gagnier, P.-Y.; Cespedes, R.; Janvier, P. (2007), "The tail of the Ordovician fish Scabambaspis", Biology Letters , 3 (1): 72–75, doi:10.1098/rsbl.2006.0557, PMC   2373808 , PMID   17443969
• Emig, C. C.; Herrera, Z. (2006), "Dignomia munsterii (Brachiopoda, Lingulata) from the Ordovician of Bolivia, with redescription of the genus", Geodiversitas , 28: 227–237
• Gagnier, P. Y.; Blieck, A.; Emig, C. C.; Sempere, T.; Vachard, D.; Vanguestaine, M. (1996), "New paleontological and geological data on the Ordovician and Silurian of Bolivia", Journal of South American Earth Sciences , 9 (5): 329–347, Bibcode:1996JSAES...9..329G, doi:10.1016/S0895-9811(96)00018-1
• Branisa, L (1965), "Los fósiles guias de Bolivia: I. Paleozoico", Boletín de Servicio Geologico de Bolivia la Paz, Bolivia, 6: 1–282