Tejra Quarry, Medenine, Unit 1 (Triassic of Tunisia)

Where: Tunisia (33.4° N, 10.4° E: paleocoordinates 4.6° S, 16.4° E)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Ouled Chebbi Formation, Illyrian (247.2 - 242.0 Ma)

• Compared to the local Ouled Chebbi Formation (Soussi et al. 2017)

• group of beds-level stratigraphic resolution

Environment/lithology: fluvial-lacustrine; claystone and sandstone

• "The first unit (Unit 1) is about 25 m thick. It is made up of the alternations of red and grey to greenish thin claystone beds with numerous thin sandstone beds showing at their bases thin conglomeratic horizons. The sandstones are composed of medium to coarse, well sorted quartz grains. Desiccation features are observed as well as numerous ripple marks on upper surfaces of thin sandstone layers. The brownish and greenish claystone intervals encountered at the base of the section are rich in conchostracans. A set of beds made up of grayish-yellowish and brownish claystones, situated about 5 m above the first conglomerate level and marking the base of the section, yielded abundant and the most diverse freshwater fauna. Most of the fossils come from yellowish layer situated at the top of the lower grayish/greenish bed. The fauna is represented by conchostracans, horseshoe crabs, freshwater bivalves, rare microconchids and lingulids. Desiccation cracks, small burrows and casts after plant roots were also present in this horizon." (Soussi et al. 2017)

Size class: macrofossils

Preservation: trace

Collection methods: Repository: Institute of Paleobiology of Polish Academy of Sciences (ZPAL)

Primary reference: M. Soussi, G. Niedźwiedzki, M. Tałanda, D. Dróżdż, T. Sulej, K. Boukhalfa, J. Mermer and B. Błażejowski. 2017. Middle Triassic (Anisian-Ladinian) Tejra red beds and Late Triassic (Carnian) carbonate sedimentary records of southern Tunisia, Saharan Platform: Biostratigraphy, sedimentology and implication on regional stratigraphic correlations. Marine and Petroleum Geology 79:222-256 [A. Dunhill/B. Allen]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 203922: authorized by Alex Dunhill, entered by Bethany Allen on 28.08.2019, edited by Matthew Clapham

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
unclassified
  -
cf. Dictyonatella sp.
Tentaculita
 Microconchida -
Microconchida indet.
Lingulata
 Lingulida - Lingulidae
Lingularia sp.
Lingularia sp. Biernat and Emig 1993
Gastropoda
 Murchisoniina - Zygopleuridae
cf. Polygyrina sp.
Bivalvia
  -
Bivalvia indet.
Bivalvia indet. Linnaeus 1758 clam
 Cardiida - Anthracosiidae
Unionites cf. longus
Xiphosura
 Xiphosurida - Limulidae
Limulitella tejraensis n. sp.
Limulitella tejraensis n. sp. Błażejowski et al. 2017 horseshoe crab
Branchiopoda
 Diplostraca -
Conchostraca indet.
Conchostraca indet. Sars 1867 clam shrimp
 Ichnofossils -
Rusophycus sp., Palaeophycus sp., Lockeia sp., Planolites sp.
Rusophycus sp. Hall 1852
Palaeophycus sp. Hall 1847
Lockeia sp. James 1879
Planolites sp. Nicholson 1873