Seccion del Rio Escondido, layer 1.: Rhuddanian, Argentina

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Crinoidea
Crinoidea indet. Miller 1821
Pterobranchia - Graptoloidea - Normalograptidae
Climacograptus normalis (Lapworth 1877)
recombined as Normalograptus normalis
Pterobranchia - Graptoloidea - Monograptidae
Clinoclimacograptus sp.
Climacograptus innotatus Nicholson 1869
recombined as Paraclimacograptus innotatus
Pterobranchia - Graptoloidea - Climacograptidae
Climacograptus cf. rectangularis
Strophomenata - Strophomenida - Leptostrophiidae
Aphanomena aff. mullochensis (Reed 1917)
    = Eostropheodonta parvula Benedetto and Montoya 2015
Wagner 2020
original and current combination Eostropheodonta chilcaensis parvula
Eostropheodonta chilcaensis (Benedetto 1995)
Benedetto and Montoya 2015
Eostropheodonta chilcaensis parvula
    = Eostropheodonta parvula Benedetto and Montoya 2015
Wagner 2020
original and current combination Eostropheodonta chilcaensis parvula
Strophomenata - Strophomenida - Rafinesquinidae
Leptaena sp. Dalman 1828
Rhynchonellata - Rhynchonellida - Leptocoeliidae
? Anabaia informal n. sp.
Rhynchonellata - Rhynchonellida - Trigonirhynchiidae
Rostricellula sp. Ulrich and Cooper 1942
Rhynchonellata - Orthida - Heterorthidae
Heterorthella precordillerana Benedetto 1995
Rhynchonellata - Orthida - Dalmanellidae
Dalmanella aff. testudinaria (Dalman 1828)
original and current combination Orthis testudinaria
Tentaculitida
Tentaculitida indet. Ljaschenko 1955
unclassified
Bryozoa indet. Ehrenberg 1831
Gastropoda
Gastropoda indet. Cuvier 1795
Bivalvia
Pelecypoda indet. Goldfuss 1820
synonym of Bivalvia
Trilobita
Trilobita indet. Walch 1771
see common names

Geography
Country:Argentina State/province:San Juan
Coordinates: 30.3° South, 68.7° West (view map)
Paleocoordinates:34.3° South, 135.2° West
Basis of coordinate:based on nearby landmark
Geographic resolution:local area
Time
Period:Silurian Epoch:Llandovery
Stage:Rhuddanian 10 m.y. bin:Silurian 1
*Epoch:Early/Lower Llandovery
Key time interval:Rhuddanian Graptolite zone: Atavograptus atavus
Age range of interval:443.80000 - 440.80000 m.y. ago
* legacy (obsolete) database fields
Stratigraphy
Formation:La Chilca
Local section:Rio Escondido Local bed:30 m
Local order:bottom to top
Stratigraphic resolution:group of beds
Stratigraphy comments: Age based on fact that beds containing the brachiopods are interbedded with or above beds of Atovograptus atavus Biozone.
Lithology and environment
Primary lithology:hummocky CS,"cross stratification",shelly/skeletal sandstone
Secondary lithology: "shale"
Lithology description: Lower part of shale and Sst...Upper part of fine-grained Sst [the part with fossils]...high-angle cross beds...hummocky cross beds...
Environment:marine indet.
Geology comments: Precordillera. Occurrences generally in dense shell accumulations; valves generally fragmented and disarticulated, indicating turbulence, possibly due to storms. In other instances the valves are articulated, less fragmented. Some cases of partial or total silicification.
Taphonomy
Modes of preservation:body,replaced with silica
Size of fossils:macrofossils
Collection methods and comments
Collection excludes:some macrofossils
Reason for describing collection:biostratigraphic analysis
Collection method comments: Brachiopods studied and listed; other higher taxa simply mentioned; graptolites listed for two of the sections that contain them. See location details.
Metadata
Database number:25093
Authorizer:M. Foote, P. Wagner Enterer:M. Foote, P. Wagner
Modifier:P. Wagner Research group:marine invertebrate
Created:2002-08-28 09:55:34 Last modified:2019-09-18 23:16:14
Access level:the public Released:2002-08-28 09:55:34
Creative Commons license:CC BY
Reference information

Primary reference:
7045. J. L. Benedetto. 1995. Braquiopodos del Silurica temprano malvinocafrico (Formacion La Chilca), Precordillera Argentina. Géobios 28(4):425-457 [M. Foote/M. Foote/J. Alroy]

Secondary references:

54722 J. L. Benedetto and E. Montoya. 2015. The Afro–South American brachiopod Castellaroina Boucot from the Silurian of the Argentine Precordillera: its origin and phylogenetic relationships. Paläontologische Zeitschrift 89:1-24 [W. Kiessling/W. Kiessling]
65064 P. Wagner. 2020. Subspecies kluges: a pointless taxonomic database to create species opinions for subspecies that then will be over-ruled and allow subspecies occurrences to be recognized as the subspecies rather than the parent species. [P. Wagner/P. Wagner/P. Wagner]