Kandreho Formation

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Kandreho Formation
Stratigraphic range: Toarcian
~180–176  Ma
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Type Geological formation
Lithology
Primary Marly limestone
Location
Coordinates 17°30′S45°18′E / 17.5°S 45.3°E / -17.5; 45.3
Approximate paleocoordinates 22°18′S24°00′E / 22.3°S 24.0°E / -22.3; 24.0
Region Mahajanga Province
CountryFlag of Madagascar.svg  Madagascar
Extent Mahajanga Basin
Type section
Named for Kandreho
Named byGeiger
Year defined2004
Outcrop of the formation in Madagascar

The Kandreho Formation is an Early Jurassic (middle or late Toarcian) geological formation of the Mahajanga Basin of Madagascar. The marly limestones of the formation were deposited in a subtidal lagoonal environment. The formation overlies the Bouleiceras and Spiriferina beds of the early Toarcian and has been correlated to the Marrat Formation of Saudi Arabia. [1] Fossils of the marine crocodylian " Steneosaurus" as well as bivalves and the ammonite Nejdia have been found in the formation. [2] [3] The name Kandreho Formation was proposed by Geiger in 2004. [4]

Contents

Fossils

Crocodyliformes

GenusSpeciesLocationMaterialNotesImages
" Steneosaurus " [1]
  • S. sp.
BehazonatyUpper jaw fragmentA thalattosuchian mesoeucrocodylian. The genus Steneosaurus is a wastebasket taxon and the current referral of this specimen is unknow
Example of coeval Thallatosuchian also referred to Steneosaurus, Macrospondylus Steneosaurus NT small.jpg
Example of coeval Thallatosuchian also referred to Steneosaurus, Macrospondylus

See also

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References

  1. 1 2 Buffetaut, Eric; Termier, Geneviéve; Termier, Henri (1981). "A teleosaurid (Crocodylia, Mesosuchia) from the Toarcian of Madagascar and its palaeobiogeographical significance". Paläontologische Zeitschrift. 55 (3–4): 313–319. doi:10.1007/bf02988145. ISSN   0031-0220.
  2. Behazonaty, SW of the basin of the Kelifely at Fossilworks.org
  3. Buffetaut et al., 1981, p.314
  4. Geiger, 2004, p.125

Bibliography