Silica Formation Unit 18 (18A,18B) (Devonian of the United States)

Where: Ohio (41.7° N, 83.7° W)

• Paleocoordinates: 31.0° S, 50.8° W (Wright 2013)

• coordinate based on nearby landmark

• local area-level geographic resolution

When: Silica Formation, Givetian (387.7 - 382.7 Ma)

• group of beds-level stratigraphic resolution

Environment/lithology: marine; pyritic, gray, calcareous, carbonaceous shale and lenticular, argillaceous limestone

• Overall sequence: Bioclastic limestone; argillaceous limestone; shale. This unit: 18B: "shale, calcareous, dark-gray, carbonaceos, strong petroliferous odor on fresh surface; weathering into light-gray angular fragments; some pyrite noted on weathered surfaces..." 18A: "shale, calcareous, gray to dark-gray, similar to unit 18B. One or more argillaceous limestone lenses may be present near base...an Aulocystis thicket or bioherm well developed in north end of North Quarry"

Primary reference: R. V. Kesling and R. B. Chilman. 1975. Strata and megafossils of the Middle Devonian Silica Formation. University of Michigan Papers on Paleontology 8:1-408 [M. Foote/M. Foote/M. Foote]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 38469: authorized by Michael Foote, entered by Michael Foote on 21.04.2004

Creative Commons license: CC0 (CC0)

Taxonomic list

Show authors, comments, and common names
Anthozoa
 Auloporida - Aulocystidae
Aulocystis auloporoidea
 Favositida - Pachyporidae
"Trachypora alpenensis" = Thamnoptychia
"Trachypora alpenensis" = Thamnoptychia tabulate coral
Crinoidea
 Taxocrinida - Taxocrinidae
Eutaxocrinus wideneri
Asteroidea
  -
Silicaster esseri
Silicaster esseri Kesling 1969 sea star
Ophiuroidea
 Oegophiurida - Protasteridae
Strataster devonicus
Strataster devonicus Kesling 1972 brittle star
Malacostraca
 Archaeostraca -
Rhinocaris ehlersi
Stenolaemata
 Tubuliporata - Hederellidae
Hederella alpenensis
Strophomenata
 Strophomenida - Chonetidae
Longispina sp.
 Orthotetida - Areostrophiidae
"Orthopleura "sp. B Imbrie"" = Imbriea
"Orthopleura "sp. B Imbrie"" = Imbriea Reily 2020
Rhynchonellata
 Spiriferida - Mucrospiriferidae
Mucrospirifer mucronatus
 Terebratulida - Rhipidiothyrididae
Rhipidothyris "sp. A", Rhipidothyris "sp. B"
 Rhynchonellida - Trigonirhynchiidae
Cupularostrum "sp. A"
Cupularostrum "sp. A" Sartenaer 1961
 Rhynchonellida - Leiorhynchidae
Leiorhynchus "sp. C"
 Orthida - Draboviidae
Sphenophragmus cf. nanus
 Orthida - Schizophoriidae
Schizophoria sp.
Schizophoria sp. King 1850
 Spiriferinida - Cyrtinidae
Cyrtina umbonata
Lingulata
  -
Lingulata indet.
Lingulata indet. Gorjansky and Popov 1985
Bivalvia
 Ostreida - Pterineidae
Leptodesma (Leiopteria) ausablensis, Cornellites flabellum
 Pectinida - Aviculopectinidae
Aviculopecten sp.
Aviculopecten sp. M'Coy 1851 scallop