Nexocrinus Association, Rhuddanian, Southern Ontario: Rhuddanian, Canada

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Asteroidea - Hadrosida - Promopalaeasteridae
? Promopalaeaster granti
Crinoidea - Diplobathrida - Dimerocrinitidae
Nexocrinus delicatulus
Crinoidea - Homocrinida - Homocrinidae
Homocrinus diminutus
see common names

Geography
Country:Canada State/province:Ontario
Coordinates: 43.8° North, 79.8° West (view map)
Paleocoordinates:22.9° South, 49.9° West
Basis of coordinate:based on political unit
Geographic resolution:local area
Time
Period:Silurian Epoch:Llandovery
Stage:Rhuddanian 10 m.y. bin:Silurian 1
Key time interval:Rhuddanian
Age range of interval:443.80000 - 440.80000 m.y. ago
Stratigraphy
Stratigraphy comments: Rhuddanian A-B. Whirlpool, Manitoulin, Cabot Head, and Power Glen Formations.
Lithology and environment
Primary lithology: calcareous sandstone
Lithology description: "calcareous sandstone"
Environment:transition zone/lower shoreface Tectonic setting:foreland basin
Geology comments: "found in proximity to, but not directly associated wiht, occurrences of the starfish Promopalaeaster? granti and the small inadunate crinoid Homocrinus diminutus" "These appear to represent opportunistic echinoderms adapted to life udner relatively unstable substrate conditions in the proximal storm-dominated sandy shelf...probably BA 2"
SEP environmental call based on given information
Taphonomy
Collection methods and comments
Reason for describing collection:paleoecologic analysis
Metadata
Database number:26686
Authorizer:M. Foote Enterer:M. Foote
Modifier:S. Peters Research group:marine invertebrate
Created:2002-10-24 07:35:08 Last modified:2003-05-14 12:20:11
Access level:the public Released:2002-10-24 07:35:08
Creative Commons license:CC BY
Reference information

Primary reference:
4379. T. J. Frest, C. E. Brett, and B. J. Witzke. 1999. Caradocian-Gedinnian echinoderm associations of Central and Eastern North America. Paleocommunities--a case study from the Silurian and Lower Devonian 638-783 [M. Foote/K. Koverman/P. Wagner]