Wiestal, Schönbauer site, fish-layer 5 (bed 1) (Triassic of Austria)

Where: Austria (47.7° N, 13.1° E: paleocoordinates 27.4° N, 17.1° E)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Seefeld Member (Hauptdolomit Formation), Alaunian (215.6 - 212.0 Ma)

• The stack of bituminous dolomicrites is assumed to be deposited coeval to a similar succession at the type locality in Seefeld (Hopf et al., 2001; Donofrio et al., 2003). There, Donofrio et al. (2003) extracted some conodonts from tempestite layers and assigned the Seefeld Member into the time span between the base of the Alaunian 2 and the Sevatian 1 (Norian, Upper Triassic). However, the dolomicrites at the Wiestal site are devoid of microfossils.

• bed-level stratigraphic resolution

Environment/lithology: basinal (); lithified, dolomitic, carbonaceous lime mudstone

• The fine-grained, regularly laminated deposits at the Wiestal site point to quiet, protected and stagnant lagoonal waters that were responsible for the remarkable and excellent fossil preservation. The undisturbed mm-scale lamination of the dolostones implies the complete absence of any benthonic, bottom-dwelling fauna. The perfect and nearly exclusive articulation of any fossil substance as well as the high TOC because of incomplete necrotic decay of organic matter, speaks in favour of a strictly anoxic water body that was developed in the Wiestal (and Seefeld) basins at greater water depths below the wave base.
• Very hard, thin- to medium-bedded, dark- to blackish-grey, bituminous dolomicritic limestones. Every bed is confined by a (sub-) mm-thick marly bedding plane. The individual beds show thicknesses between 10 and 60 cm, which can vary across short distances – some layers show a lateral dwindling within a few metres. Most of the horizons exhibit a very fine lamination at a sub-mm scale, often accompanied by synsedimentary load marks being similar to midget normal faults with mm-sized offsets (Fig. 3). The preservation of fine sedimentary lamination implies the absence of endobenthic sediment feeders such as small crustaceans, gastropods and annelids.

Size class: macrofossils

Preservation: adpression

Collected in 2012-2015

• Repository: private collections of some of the above authors (abbreviations: collection Gerhard Wolf, Bad Vigaun: CGW; collection Joop van der Wielen, Salzburg: CJW; collection Thomas Hornung, Berchtesgaden: CTH; collection Burgmuseum Golling: CBG).

Primary reference: T. Hornung, I. Kogan, G. Moosleitner, G. Wolf, and J. Wielen. 2019. The Norian fish deposits of Wiestal ("Seefeld Member", Northern Calcareous Alps, Salzburg, Austria) - taxonomy and palaeoenvironmental implications. Austrian Journal of Earth Sciences 112:125-165 [M. Clapham/M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 207547: authorized by Matthew Clapham, entered by Matthew Clapham on 17.01.2020

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Osteichthyes
 Saurichthyiformes - Saurichthyidae
Saurichthys deperditus
Saurichthys deperditus Costa 1862 ray-finned fish
Actinopteri
 Semionotiformes - Callipurbeckiidae
Paralepidotus ornatus
Paralepidotus ornatus Agassiz 1832
 Semionotiformes - Macrosemiidae
Legnonotus krambergeri
 Pholidophoriformes - Pholidophoridae
Pholidophorus latiusculus