Upper Visby Beds:Fossils of Gotland found only in Vis. Beds (Manten 1971, T.XVI) (Silurian of Sweden)

Where: Gotland, Sweden (57.6° N, 18.3° E: paleocoordinates 21.6° S, 3.0° W)

• coordinate based on political unit

• local area-level geographic resolution

When: Upper Visby Beds Formation, Sheinwoodian (433.4 - 430.5 Ma)

• group of beds-level stratigraphic resolution

Environment/lithology: offshore ramp; lithified, gray, blue marl and lithified, pyritic, gray limestone

• SEP: Silurian of Gotland has been variably described as a ramp and platform. Based on my read of the literature, I think if falls best into the ramp category. From Samtleben et al. (1996). Geol. Rundsch 85:278-292; "This series of micritic limestones and marls (of the Lower Visby) shows upward increasing intercalations of biodetritic limestones (packstones, in the upper part grainstones) which indicate episodes of wave-base influence on the sea floor...erosional discordances and channel structures indicate the effects of bottom currents."
• ...thin layers of rather soft bluish grey marlstone which alternate with harder marly limestone. The latter is dense to finely crystalline and light grey in color. Lithologically, therefore, there is little difference between the Upper Visby Beds and the underlying Lower Visby sediments...In the marly limestone, pyrite is found locally in isolated crystals or in groups of crystals... (Manten 1971, p. 280)

Primary reference: A. A. Manten. 1971. Silurian Reefs of Gotland. Developments in Sedimentology 13:1-539 [M. Foote/M. Foote/P. Wagner]more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 13675: authorized by Michael Foote, entered by Michael Foote on 17.04.2002, edited by Pete Wagner

Creative Commons license: CC BY (attribution)

Taxonomic list

• List restricted to "fossils which in Gotland are found only in the Visby Beds".
Anthozoa
 Heliolitida - Halysitidae
Catenipora escharoides Lamarck 1816 tabulate coral
 Favositida - Alveolitidae
Planalveolites fougti tabulate coral
 Favositida - Theciidae
Thecia hisingeri tabulate coral
 Stauriida - Aulophyllidae
 Stauriida - Lykophyllidae
"Phaulactis angusta" = Phaulactis, "Lykophyllum tabulatum" = Phaulactis
"Phaulactis angusta" = Phaulactis horn coral
"Lykophyllum tabulatum" = Phaulactis horn coral
 Cystiphyllida - Tryplasmatidae
"Pholidophyllum tabulatum" = Tryplasma
"Pholidophyllum tabulatum" = Tryplasma horn coral
 Cystiphyllida - Goniophyllidae
Trilobita
 Phacopida - Encrinuridae
Ostracoda
 Palaeocopida - Beyrichiidae
 Palaeocopida - Craspedobolbinidae
Strophomenata
 Strophomenida - Leptaenoideidae
Liljevallia gotlandica Hedstrom 1917
Rhynchonellata
 Orthida - Dalmanellidae
 Atrypida - Anazygidae
""Rhynchonella" exigua" = Zygatrypa exigua
""Rhynchonella" exigua" = Zygatrypa exigua Lindström 1861
Stenolaemata
 Trepostomida - Monticuliporidae
 Cystoporata - Ceramoporidae
Gastropoda
 Euomphalina - Platyceratidae
"Cyclonema delicatulum" = Cyclonema delicatula
"Cyclonema delicatulum" = Cyclonema delicatula Lindström 1884 snail
 Euomphalina - Oriostomatidae
"Poleumita roemeri" = Oriostoma roemeri, "Cyclonema giganteum" = Oriostoma giganteum
"Poleumita roemeri" = Oriostoma roemeri Lindström 1884 snail
"Cyclonema giganteum" = Oriostoma giganteum Lindström 1884 snail
 Euomphalina - Holopeidae
"Callonema scalariforme" = Holopea scalariforme
"Callonema scalariforme" = Holopea scalariforme Lindström 1884 snail
 Euomphalina - Elasmonematidae
"Callonema obesum" = Discordichilus obesum
"Callonema obesum" = Discordichilus obesum Lindström 1884 snail