'Entomis' migrans Community in Prague Basin: Ludfordian, Czech Republic
List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
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Pterobranchia
- Graptoloidea
- Monograptidae
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Bohemograptus bohemicus
(Barrande 1850)
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Cephalopoda
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Cephalopoda indet.
Cuvier 1797
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Ostracoda
- Cypridinida
- Bolbozoidae
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Entomis migrans
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| synonym of Entomozoe | ||||||||||
| genus name in quotes | ||||||||||
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Bolbozoe bohemica
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| rare | ||||||||||
| see common names | ||||||||||
Geography
| Country: | Czech Republic |
| Coordinates: | 49.9° North, 14.0° East (view map) |
| Paleocoordinates: | 51.2° South, 56.7° East |
| Basis of coordinate: | based on nearby landmark |
| Geographic resolution: | local area |
Time
| Period: | Silurian | Epoch: | Ludlow |
| Stage: | Ludfordian | 10 m.y. bin: | Silurian 2 |
| *International age/stage: | Early/Lower Ludfordian | ||
| Key time interval: | Ludfordian | Zone: | Monograptus fritschi linearis |
| Age range of interval: | 425.60000 - 423.00000 m.y. ago | ||
| * legacy (obsolete) database fields | |||
Stratigraphy
| Stratigraphic resolution: | group of beds |
Lithology and environment
| Primary lithology: | gray,red or brown calcareous "shale" |
| Includes fossils? | Y |
| Lithology description: "Disarticulated shells occur abundantly in calcareous, brownish-grey shales together with rare Bolbozoe bohemica, scattered nektobenthic cephalopod shells, and rare graptolites." | |
| Environment: | marine indet. |
| Geology comments: "In the Prague Basin this faceis represent the deepest facies. Benthic fauna is usually very rare here, and there is no evidence for current action above the sea botom. The sediments correspond to below wave base conditions. Pelagic ostracodes together with graptolites and cephalopod shells were carried into this part of the basin by surface currents.
The lack of benthic fauna speaks for unfavorable sea bottom conditions, low oxygen content, and very little circulation, well below wave base. Pelagic ostracodes were carried together with cephalopod shells into this part of the basin by surface currents. E. migrans also occurs abundantlyh in the limestone facies... [Shale horizons with B. bohemica alternate with horizons dominated by 'Entomis' migrans. B. bohemica never collected in limestones, while E. migrans occurs in cephalopod Lst. facies, which is shallower, subtidal. Possibly this is explained by preferred depths of these pelagic forms.] Alternation of the two communities in the calcareous shales may be due to changes in the circulation pattern above the sea bottom." | |
Taphonomy
Collection methods and comments
| Collection excludes: | some macrofossils |
| Reason for describing collection: | paleoecologic analysis |
| Collection method comments: Despite broad distribution of community, it seems clear from the description that the elements are found at the type locality. | |
| Taxonomic list comments:Ostracodes are the focus. Other groups mentioned but not listed in detail. | |
Metadata
| Database number: | 14192 | ||
| Authorizer: | M. Foote | Enterer: | M. Foote |
| Modifier: | M. Foote | Research group: | marine invertebrate |
| Created: | 2002-05-22 12:30:57 | Last modified: | 2006-09-15 15:14:05 |
| Access level: | the public | Released: | 2002-05-22 12:30:57 |
| Creative Commons license: | CC BY |
Reference information
Primary reference:
| 6282. | J. Kříž. 1999. Bivalvia communities of Bohemian type from the Silurian and Lower Devonian carbonate facies. In A. J. Boucot. J. D. Lawson (ed.), Paleocommunities -- A case study from the Silurian and Lower Devonian 229-252 [M. Foote/M. Foote/P. Wagner] |