Delthyris elevata-Howellella elegans Community in Holmestrand District (Silurian of Norway)

Where: Norway (68.8° N, 15.0° E: paleocoordinates 12.2° S, 9.5° W)

• coordinate based on nearby landmark

• local area-level geographic resolution

When: Steinsfjorden Formation, Sheinwoodian (433.4 - 430.5 Ma)

• Middle part of Steinsfjorder Fmn., Late Sheinwoodian or Early Homerian.

• formation-level stratigraphic resolution

Environment/lithology: marine; argillaceous carbonate

• "The facies represent a low energy, muddly lagoonal environment with periodically stagnant waters, as indicated by pseudomorphs of sulfate minerals, although these minerals might be more suggestive of within sediment conditions rather than sediment surface and overlying water conditions. In similar environments, where the sed. rate was high and the bottom v. soft, the Microsphaeridiorhynchus nucula Comm. usually replaced this one. this is probably a BA 2 to 3 unit."
• "This is a low diversity comm. developed in carbonates where brachiopods are eurytopic (present in most communities in the succession)..."

Collection methods: Table 22.4 gives absolute and relative abundances.

Primary reference: B. G. Baarli, H. B. Keilen, and M. E. Johnson. 1999. Silurian communities of the Oslo Region, Norway. In A. J. Boucot and J. D. Lawson (eds.), Paleocommunities--a case study from the Silurian and Lower Devonian 327-349 [M. Foote/M. Foote/P. Wagner]more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 14275: authorized by Michael Foote, entered by Michael Foote on 29.05.2002

Creative Commons license: CC BY (attribution)

Taxonomic list

• Some taxa not listed to genus level.
Trilobita
 Phacopida - Calymenidae
Calymenidae indet. Milne-Edwards 1840 trilobite
Ostracoda
 Leperditicopida -
Herrmannina sp. Kegel 1933 ostracod
Strophomenata
 Strophomenida - Rafinesquinidae
"Leptaena depressa" = Leptaena (Leptaena) depressa
"Leptaena depressa" = Leptaena (Leptaena) depressa Sowerby 1824
Rhynchonellata
 Athyridida - Athyrididae
cf. Glassina sp. Hall and Clarke 1893
 Terebratulida - Megathyrididae
"Rhynchotreta cuneata" = Argyrotheca cuneata
"Rhynchotreta cuneata" = Argyrotheca cuneata Dalman 1828
 Spiriferida - Delthyrididae
Howellella elegans Muir-Wood 1925
Delthyris elevata Dalman 1828
 Atrypida - Glassiidae
 Rhynchonellida - Trigonirhynchiidae
 Rhynchonellida - Rhynchotrematidae
"Ferganella diodonta" = Stegerhynchus diodontus
"Ferganella diodonta" = Stegerhynchus diodontus Dalman 1828
Bivalvia
 Ostreida - Pterineidae
Cephalopoda
 Orthoceratida -
"Orthoceratida indet." = Orthocerida
"Orthoceratida indet." = Orthocerida Kuhn 1940
Orthoceratid sp. A