Gara Sbaa (MSNM collection): Late/Upper Cenomanian, Morocco

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Crinoidea - Comatulida
Comatulida indet. Clark 1908
Actinopteri - Amiiformes
Amiiformes indet. Hay 1929
Actinopteri - Aulopiformes - Dercetidae
aff. Rhynchodercetis sp. Arambourg 1943
Actinopteri - Pycnodontiformes - Pycnodontidae
Pycnodontidae indet. (Agassiz 1833)
Xiphosura - Xiphosurida - Limulidae
Xiphosura indet. (Latreille 1802)
    = Mesolimulus tafraoutensis n. sp. Lamsdell et al. 2020
Lamsdell et al. 2020
Malacostraca - Isopoda
Isopoda indet. Latreille 1817
Malacostraca - Decapoda - Galatheidae
Cretagalathea exigua n. gen., n. sp. Garassino et al. 2008
3 specimens
Galathea sahariana n. sp. Garassino et al. 2008
4 specimens
Malacostraca - Decapoda - Paragalatheidae
Paragalathea africana n. sp. Garassino et al. 2008
1 specimen
Malacostraca - Decapoda - Telamonocarcinidae
Telamonocarcinus cf. gambalatus Larghi 2004
1 specimen
Malacostraca - Decapoda - Cenomanocarcinidae
Corazzatocarcinus cf. hadjoulae (Roger 1946)
2 specimens
Malacostraca - Decapoda
Glypheoidea indet. Winckler 1882
1 specimen
Malacostraca - Decapoda - Glypheidae
Glyphea garasbaaensis n. sp. Garassino et al. 2008
15 specimens
Malacostraca - Decapoda
Caridea indet. Dana 1852
1 specimen
Malacostraca - Decapoda - Penaeidae
Penaeidae indet. Rafinesque 1815
3 specimens
Cretapenaeus berberus Garassino et al. 2006
3 specimens
Insecta - Hemiptera
Homoptera indet. Leach 1815
see common names

Geography
Country:Morocco
Coordinates: 30.5° North, 4.8° West (view map)
Paleocoordinates:17.8° North, 4.8° West
Basis of coordinate:stated in text
Geographic resolution:outcrop
Time
Period:Cretaceous Epoch:Late/Upper Cretaceous
Stage:Cenomanian 10 m.y. bin:Cretaceous 5
Key time interval:Late/Upper Cenomanian
Age range of interval:100.50000 - 93.90000 m.y. ago
Stratigraphy
Formation:Akrabou
Stratigraphic resolution:group of beds
Stratigraphy comments: There are no calcareous fossils in the Gara Sbaa Lagerstätte and, consequently, it has proved difficult to establish the precise age of the deposit. The underlying Kem Kem beds, in this region resting on folded Palaeozoic strata, has been dated as Albian or Cenomanian on account of its vertebrate remains. However, over most of the outcrop the vertebrate-bearing part of the Kem Kem beds is overlain by a series of variegated mudstones, thin sandstones and evaporites for which there is no age determination. These mudstones pass up into marls and shelly limestones and, at Gara Sbaa, into the fossiliferous laminated limestone described here. The marls and shelly limestones yield abundant examples of Ilymatogyra cf. africana, a bivalve that usually indicates a mid to early Late Cenomanian age (Ettachfini and Andreu, 2004; Dhondt and Jaillard, 2005). In the Goulmima region of southern Morocco laterally equivalent carbonates of the Akrabou Formation have been dated as Late Cenomanian to Turonian on account of their marine benthic and planktonic foraminiferan assemblages (Ettachfini and Andreu, 2004). It is highly likely that the Gara Sbaa Lagerstätte is of Late Cenomanian or Early Turonian age but because there are no strata overlying the laminites, a minimum age cannot be determined at this locality.
Previously under Gara Sbaa member of the Akrabou Formation, but the Gara Sbaa unit is now considered a Formation, and is older than the Akrabou Formation (see Ibrahim et al. 2020)
Lithology and environment
Primary lithology:planar lamination,dolomitic lithified lime mudstone
Lithology description: The fossil-bearing parts of the Gara Sbaa laminites are restricted to a few horizons within the finely laminated dolomitised limestone with laminae of just 1e2 mm in thickness. In the middle to upper part of the unit the laminae are planar with few interruptions, but toward the base some bedding planes exhibit ripple marks with wave lengths of w50 mm
Environment:lagoonal/restricted shallow subtidal
Geology comments: The Gara Sbaa fossil locality represents a shallow marine plattenkalk Konservat Lagerstätte deposited during the latest Cenomanian marine transgression, perhaps under the influence of widespread oceanic anoxia. Its fossil assemblage is dominated by marine fishes with rarer input from nearby terrestrial sources.
Taphonomy
Modes of preservation:body,mold/impression,soft parts
Lagerst�tten type:conservation
Size of fossils:macrofossils
Collection methods and comments
Reason for describing collection:taxonomic analysis
Collection method comments: Repository: Museo di Storia Naturale di Milano, Italy (MSNM)
Metadata
Also known as:Agoult
Database number:127539
Authorizer:C. Schweitzer, M. Clapham Enterer:E. Johnson, M. Clapham
Modifier:G. Varnham Research group:decapod,marine invertebrate
Created:2012-05-17 06:42:34 Last modified:2022-04-04 05:52:26
Access level:the public Released:2012-05-17 06:42:34
Creative Commons license:CC BY
Reference information

Primary reference:
41571.decapod A. Garassino, A. De Angeli, and G. Pasini. 2008. New decapod assemblage from the Upper Creaceous (Cenomanian-Turonian) of Gara Sbaa, southeastern Morocco. Atti della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano 149(1):37-67 [C. Schweitzer/E. Johnson/M. Clapham]

Secondary references:

74866 J. C. Lamsdell, J. N. Tashman, G. Pasini and A. Garassino. 2020. A new limulid (Chelicerata, Xiphosurida) from the Late Cretaceous (Cenomanian-Turonian) of Gara Sbaa, southeast Morocco. Cretaceous Research 106(104230) [M. Clapham/M. Clapham]