Jarcas stream, Negra Muerta, Sella Valley, Bolivia (Silurian to of Bolivia)

Where: Tarija dept., Bolivia (21.4° S, 64.7° W: paleocoordinates 54.3° S, 121.4° W)

• outcrop-level geographic resolution

When: upper Member (Lipeon Formation), Gorstian to Gorstian (427.4 - 419.2 Ma)

• Age is determined through field relations and some less-than-diagnostic invertebrate fossils (originally designated as the Kirusillas Fm.)

• formation-level stratigraphic resolution

Environment/lithology: deltaic; lithified, green siltstone and lithified, green sandstone

• Regressive regime in front of a prograding delta complex; distributary mouth bars were formed in the marginal marine environments.
• Ove-green finely micaceous rusty weathering silty mudstones, siltstones and fine sandstones dip consistently to the south at 70-80 degrees.

Size classes: macrofossils, microfossils

Preservation: adpression, permineralized, coalified, original carbon, original sporopollenin, replaced with limonite

Collection methods: mechanical,

• info taken from Morel et al 1995; Edwards et al 2001

Primary reference: B. Petriella and R. Suarez Soruco. 1989. Presencia de plantas terrestres, probablemente vosculares, en las formaciones Kirusillas y Tarabuco (Lampayano-Silurico Superior) de Bolivia. Revista Tecnica de YPFB 10:119-121 [P. Gensel/M. Kotyk]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 11158: authorized by Pat Gensel, entered by Michele Kotyk on 23.07.2001

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
unclassified
  -
cf. Tarrantia sp.1, Protista indet.1
Protista indet.1 Haeckel 1866
Algae resembling Buthotrephis or Hungerfordia.
Psilophytopsida
 Psilophytales -
Cooksonia cf. caledonica2, ? Cooksonia sp., ? Cooksonia sp.1, cf. Cooksonia pertoni1, cf. Cooksonia hemisphaerica1
? Cooksonia sp. Lang 1937
? Cooksonia sp.1 Lang 1937
Hostinella
  -
Hostinella sp.
Hostinella sp. Barrande 1882
3 types of axes were distinguished by Edwards et al 2001
Rhyniaceae
  - Rhyniaceae
cf. Steganotheca sp., cf. Steganotheca sp.
cf. Steganotheca sp. Edwards 1970
Morel et al. note that this identification is shakey at best.
cf. Steganotheca sp. Edwards 1970
Morel et al. note that this identification is shakey at best. Edwards et al 2001 note it too however
1Edwards et al. 2001; 2Morel et al. 1995