Halla Beds Brachiopods: Homerian, Sweden

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
unclassified
Leptaenioidea silurica
Strophomenata - Strophomenida - Furcitellidae
Pentlandina loveni (Verneuil 1848)
Strophomenata - Strophomenida - Strophochonetidae
Protochonetes minimus (Sowerby 1839)
Strophomenata - Strophomenida
Strophochonetes cingulatus (Lindström 1861)
Strophomenata - Orthotetida - Triplesiidae
Plectotreta lindstroemi Ulrich and Cooper 1936
Strophomenata - Orthotetida - Chilidiopsidae
Morinorhynchus adnatus (Hedström 1917)
Orthotetes adnata
Chileata - Dictyonellida - Eichwaldiidae
Dictyonella capewellii (Davidson 1848)
recombined as Eodictyonella capewellii
Rhynchonellata - Spiriferida - Cyrtiidae
Eospirifer radiatus (Sowerby 1834)
Cyrtia exporrecta (Wahlenberg 1818)
recombined as Cyrtia exporrectus
Rhynchonellata - Spiriferida - Delthyrididae
Howellella elegans Muir-Wood 1925
Rhynchonellata - Spiriferida - Cyrtinopsidae
Kozlowskiellina deltidialis (Hedstrom 1923)
Rhynchonellata - Athyridida - Rhynchospirinidae
Homoeospira baylei (Davidson 1848)
Rhynchonellata - Athyridida - Meristellidae
Whitfieldella sp. Hall and Clarke 1893
Meristina obtusa (Dalman 1828)
Rhynchonellata - Rhynchonellida - Hebetoechiidae
Sphaerirhynchia spp.
Rhynchonellata - Rhynchonellida - Trigonirhynchiidae
? Microsphaeridiorhynchus nucula (Sowerby 1839)
Rhynchotreta cuneata (Dalman 1828)
? Ancillotoechia ? bidentata (Hisinger 1827)
Rhynchonellata - Pentamerida - Gypidulidae
Gypidula galeata (Dalman 1828)
Rhynchonellata - Pentamerida - Pentameridae
Pentamerus gothlandicus Lebedev 1892
Rhynchonellata - Orthida - Dalmanellidae
? Isorthis ? crassa (Lindström 1861)
Rhynchonellata - Orthida - Rhipidomellidae
Dalejina hybrida (Sowerby 1839)
Rhynchonellata - Atrypida - Atrypidae
Atrypa reticularis (Linnaeus 1758)
original and current combination Anomia reticularis
Rhynchonellata - Atrypida - Lissatrypidae
Glassia obovata (Sowerby 1839)
recombined as Lissatrypa obovata
see common names

Geography
Country:Sweden State/province:Gotland
Coordinates: 57.5° North, 18.4° East (view map)
Paleocoordinates:19.7° South, 2.6° West
Basis of coordinate:based on political unit
Geographic resolution:local area
Time
Period:Silurian Epoch:Wenlock
Stage:Homerian 10 m.y. bin:Silurian 2
*Epoch:Late/Upper Wenlock
Key time interval:Homerian
Age range of interval:430.50000 - 427.40000 m.y. ago
* legacy (obsolete) database fields
Stratigraphy
Formation:Halla Beds
Stratigraphic resolution:group of beds
Stratigraphy comments: Correlation from Jeppsson (1983), Fossils and Strata 15:128
Lithology and environment
Primary lithology:bioturbation argillaceous "limestone"
Secondary lithology:ooidal "limestone"
Lithology description: Ref. 11073: "Halla Beds (15m): In the eastern part of Gotland a series of shallow marine sediments was deposited on a discontinuity plane. Pure oolites at the base are overlain by bioturbated argillaceous limestones with an abundant but impoverished marine fauna, indicating marginal marine to lagoonal conditions. These limestones grade into conglomeratic oncolites which are interrupted by evenly abraded hardgrounds..."
Environment:marine indet.
Taphonomy
Collection methods and comments
Reason for describing collection:taxonomic analysis
Metadata
Database number:13528
Authorizer:M. Foote Enterer:M. Foote
Modifier:M. Foote Research group:marine invertebrate
Created:2002-04-12 09:00:37 Last modified:2006-09-15 15:15:11
Access level:the public Released:2002-04-12 09:00:37
Creative Commons license:CC BY
Reference information

Primary reference:

6126. M. G. Bassett and L. R. M. Cocks. 1974. A review of Silurian brachiopods from Gotland. Fossils and Strata (3)1-56 [M. Foote/M. Foote/M. Foote]

Secondary references:

11073 C. Samtleben, A. Munnecke, T. Bickert and J. Paetzold. 1996. The Silurian of Gotland (Sweden): facies interpretation based on stable isotopes in brachiopod shells. Geologische Rundschau 85:278-292 [M. Foote/M. Foote/M. Foote]