‘‘Rincon", ‘‘Escuela Seccional de Puesto Grande’’, Tarija [Pircancha Fm] (Ordovician of Bolivia)

Where: Bolivia (21.2° S, 65.1° W: paleocoordinates 45.7° S, 128.8° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Baltograptus deflexus graptolite zone, Pircancha Formation, Moridunian (478.6 - 471.8 Ma)

• STRATIGRAPHIC RELATIONS: From the Pircancha Fm, for which lithostratigraphic relations are not discussed. AGE: Lower Arenig, on the basis of graptolite biostratigraphy. STRATIGRAPHIC POSITION: From the basal 150 m of the about 1,800 m thick lower

•formation.

•JA: switched from Arenig to Moridunian because age is specifically given as "early Arenig (Moridunian)"

• group of beds-level stratigraphic resolution

Environment/lithology: offshore; brown, green, silty mudstone

• ENVIRONMENT: Open shelf environment; deposition below wave base, but above storm wave base. The apparent lack of benthic fossils combined with rather rare occurrences of trace fossils is interpreted as being due to high depositional rates, unsupportive muddy substrates, cold climate, and oxygen deficiency as mentioned above.
• SPECIFIC LITHOLOGY: Greenish-brown weathered silty mudstone. LITHIFICATION: Unknown.

Size class: macrofossils

Preservation: replaced with pyrite

Reposited in the MfN

Collection methods: surface (in situ),

• COLLECTOR: Not stated in text. REPOSITORY: Museum für Naturkunde, Humboldt-Universität, Berlin.

Primary reference: B.-D. Erdtmann, B. Weber, H.-P. Schultze and S. Egenhoff. 2000. A possible agnathan plate from the lower Arenig (Lower Ordovician) of South Bolivia. Journal of Vertebrate Paleontology 20(2):394-399 [A. Hendy/A. Hendy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 90413: authorized by Austin Hendy, entered by Austin Hendy on 19.07.2009

Creative Commons license: CC BY (attribution)

Taxonomic list

• COVERAGE: Exhaustive for macrofossils and vertebrates. NOMENCLATURE: Authoritative publication with modern nomenclature and species-resolution identifications.
Pterobranchia
 Graptoloidea - Phyllograptidae
Pseudophyllograptus densus Tornquist 1879 graptolite
Tetragraptus cf. amii Elles and Wood 1902 graptolite
 Graptoloidea - Dichograptidae
Didymograptus cf. suecicus Tullberg 1880 graptolite
 Graptoloidea - Didymograptidae
Baltograptus deflexus Elles and Wood 1901 graptolite
Agnatha
  -
Pircanchaspis rinconensis n. sp. Erdtmann et al. 2000 jawless fish