Lameta Formation
Stratigraphic range: Maastrichtian
~70–66 Ma
↓
Exposure of the Lameta Formation at its type locality of Lameta
TypeGeological formation
UnderliesIntertrappean Beds, Deccan Traps deposits
OverliesJabalpur Group or Precambrian Basement
Area5,000 km2 (1,900 sq mi)
ThicknessVariable, typically 18–45 m (59–148 ft)
Lithology
PrimaryClaystone, sandstone limestone
OtherConglomerate
Location
Coordinates23°12′N 80°00′E / 23.2°N 80.0°E / 23.2; 80.0
Approximate paleocoordinates24°42′S 63°12′E / 24.7°S 63.2°E / -24.7; 63.2
RegionWestern India
Country India
ExtentMadhya Pradesh, Gujarat, Maharashtra, Andhra Pradesh, Telangana
Type section
Named forLameta Ghat
Lameta Formation is located in India
Lameta Formation
Lameta Formation (India)

The Lameta Formation, also known as the Infratrappean Beds (not to be confused with the contemporaneous Intertrappean Beds), is a sedimentary geological formation found in Madhya Pradesh, Gujarat, Maharashtra, Telangana, and Andhra Pradesh, India, associated with the Deccan Traps.[1] It is of Maastrichtian age (Late Cretaceous), and is notable for its dinosaur fossils. Many dubious names have been created for isolated bones, but several genera of dinosaurs from these rocks are well-supported, including the titanosaur sauropod Isisaurus and the abelisaurs Indosaurus, Indosuchus, Laevisuchus, and Rajasaurus.[2] As well as mammals, snakes and other fossils.

Lithology

The formation is underlain by the Lower Cretaceous sedimentary "Upper Gondwana Sequence" also known as the Jabalpur Formation, and is overlain by the Deccan Traps basalt. The Lameta Formation is only exposed at the surface as small isolated outcrops associated with the Satpura Fault. The lithology of the formation, depending on the outcrop, consists of alternating clay, siltstone and sandstone facies, deposited in fluvial and lacustrine conditions. The environment at the time of deposition has alternatively been considered semi-arid, or tropical humid.[3][4]

Fossil content

Dinosaurs

Color key
Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.
Life restoration of dinosaurs in Lameta Formation
Sauropods
Genus Species Location Stratigraphic position Material Notes Images
Isisaurus I. colberti Dongargaon Hill A titanosaur.
Jainosaurus J. septentrionalis Bara Simla "Basicranium and partial postcranial skeleton."[5] A titanosaur.
Titanosaurus T. blanfordi "Caudal vertebrae."[6]
T. indicus "Teeth"[7]
Megaloolithus[8] M. jabalpurensis

M. megadermus M. cylindricus M. dhoridungriensis M. walpurensis M. problematica M. khempurensis M. Sp.

Sauropod egg fossils
Theropods
Genus Species Location Stratigraphic position Material Notes Images
Compsosuchus C. solus "Vertebrae" Previously considered a Noasauridnow considered an indeterminate Abelisaurid[9]
Coeluroides C. largus Bara Simla "Isolated vertebrae."[10] A Indeterminate theropod also known from Dabrazhin Formation of Kazakhstan
Dryptosauroides D. grandis Bara Simla "Vertebrae."[10]
Indosaurus I. matleyi Bara Simla Partial skeleton, including a partial skull.[11]
Indosuchus I. raptorius Bara Simla Cranial remains, including two braincases, as well as a nearly complete skeleton.[11] An abelisaurid theropod.
Jubbulpuria J. tenuis "Vertebrae."[10] Likely junior synonym of Laevisuchus[12]
Lametasaurus L. indicus Bara Simla "Sacrum, ilia, tibia."[10] "Sacrum, ilia, tibia, spines, armor."[13]
Laevisuchus L. indicus Bara Simla Only vertebrae.[11] A noasaurid
Ornithomimoides O. barasimlensis Bara Simla "Vertebrae."[10] An abelisaurid[12]
O. mobilis Bara Simla "Vertebrae"[10]
Orthogoniosaurus O. matleyi Bara Simla "Tooth"[10]
Rahiolisaurus R. gujaratensis Rahioli Village An abelisaurid.
Rajasaurus R. narmadensis Temple Hill, Rahioli A partial skeleton consists of maxillae, premaxillae, braincase, and quadrate bone on the skull; and spine, hip bone, legs, and tail in post-cranial remains. An abelisaurid.
Noasauridae Indeterminate A partial dentary[12] A ceratosaur
Ornithischian
Genus Species Location Stratigraphic position Material Notes Images
Brachypodosaurus B. gravis "Humerus."[14] May not be dinosaurian
Spheroolithus? Sp. Polgaon,

Tidkepar

Egg fossils Questionably assigned to this genus[15]
Deltapodus[16] Solitary footprint Possibly a Late Cretaceous Stegosaur, Like Dravidosaurus

Reptile

Snakes

Genus Species Location Stratigraphic position Material Notes Images
Sanajeh S. indicus A skull, precloaca vertebrae and ribs. A madtsoiid snake
Sanajeh about to attack a titanosaur hatchling
Madtsoia M. pisdurensis[17] A madtsoiid snake

Turtles

Genus Species Location Stratigraphic position Material Notes Images
Jainemys J. pisdurensis A bothremydid side-necked turtle

See also

References

  1. ^ Wilson Mantilla, Gregory P.; Renne, Paul R.; Samant, Bandana; Mohabey, Dhananjay M.; Dhobale, Anup; Tholt, Andrew J.; Tobin, Thomas S.; Widdowson, Mike; Anantharaman, S.; Dassarma, Dilip Chandra; Wilson Mantilla, Jeffrey A. (2022-04-01). "New mammals from the Naskal intertrappean site and the age of India's earliest eutherians". Palaeogeography, Palaeoclimatology, Palaeoecology. 591: 110857. doi:10.1016/j.palaeo.2022.110857. ISSN 0031-0182.
  2. ^ Weishampel et al., 2004, pp.517-606
  3. ^ Srivastava, Ashok K.; Mankar, Rupesh S. (January 2015). "Lithofacies architecture and depositional environment of Late Cretaceous Lameta Formation, central India". Arabian Journal of Geosciences. 8 (1): 207–226. doi:10.1007/s12517-013-1192-y. ISSN 1866-7511. S2CID 67851941.
  4. ^ Kumari, Anjali; Singh, Seema; Khosla, Ashu (January 2021). "Palaeosols and palaeoclimate reconstruction of the Maastrichtian Lameta Formation, Central India". Cretaceous Research. 117: 104632. Bibcode:2021CrRes.11704632K. doi:10.1016/j.cretres.2020.104632. S2CID 224946979.
  5. ^ "Table 13.1," in Weishampel, et al. (2004). Page 269.
  6. ^ "Table 13.1," in Weishampel, et al. (2004). Page 270.
  7. ^ "Table 13.1," in Weishampel, et al. (2004). Page 271.
  8. ^ Khosla, Ashu; Lucas, Spencer G. (2020), "Discussion: Oospecies Diversity, Biomineralization Aspects, Taphonomical, Biostratigraphical, Palaeoenvironmental, Palaeoecological and Palaeobiogeographical Inferences of the Dinosaur-Bearing Lameta Formation of Peninsular India", Late Cretaceous Dinosaur Eggs and Eggshells of Peninsular India, Cham: Springer International Publishing, vol. 51, pp. 207–271, doi:10.1007/978-3-030-56454-4_5, ISBN 978-3-030-56453-7, retrieved 2024-01-21
  9. ^ Mohabey, D. M.; Samant, B.; Vélez-Rosado, K. I.; Wilson Mantilla, J. A. (2024). "A review of small-bodied theropod dinosaurs from the Upper Cretaceous of India, with description of new cranial remains of a noasaurid (Theropoda: Abelisauria)". Journal of Vertebrate Paleontology. e2288088. doi:10.1080/02724634.2023.2288088.
  10. ^ a b c d e f g "Table 3.1," in Weishampel, et al. (2004). Page 50.
  11. ^ a b c "Table 3.1," in Weishampel, et al. (2004). Page 49.
  12. ^ a b c Mohabey, Dhananjay M.; Samant, Bandana; Vélez-Rosado, Kevin I.; Wilson Mantilla, Jeffrey A. (2024-02-07). "A review of small-bodied theropod dinosaurs from the Upper Cretaceous of India, with description of new cranial remains of a noasaurid (Theropoda: Abelisauria)". Journal of Vertebrate Paleontology. doi:10.1080/02724634.2023.2288088. ISSN 0272-4634.
  13. ^ "Table 17.1," in Weishampel, et al. (2004). Page 368.
  14. ^ "Table 17.1," in Weishampel, et al. (2004). Page 367.
  15. ^ Khosla, Ashu; Lucas, Spencer G. (2020), "Indian Late Cretaceous Dinosaur Nesting Sites and Their Systematic Studies", Late Cretaceous Dinosaur Eggs and Eggshells of Peninsular India, Cham: Springer International Publishing, vol. 51, pp. 117–205, doi:10.1007/978-3-030-56454-4_4, ISBN 978-3-030-56453-7, retrieved 2024-02-13
  16. ^ Galton, Peter M.; Ayyasami, Krishnan (2017-07-01). "Purported latest bone of a plated dinosaur (Ornithischia: Stegosauria), a "dermal plate" from the Maastrichtian (Upper Cretaceous) of southern India". Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen. 285 (1): 91–96. doi:10.1127/njgpa/2017/0671. ISSN 0077-7749.
  17. ^ Mohabey, D.M.; Head, J.J.; Wilson, J.A. (2011). "A new species of the snake Madtsoia from the Upper Cretaceous of India and its paleobiogeographic implications". Journal of Vertebrate Paleontology. 31 (3): 588–595. Bibcode:2011JVPal..31..588M. doi:10.1080/02724634.2011.560220. S2CID 129792355.

Bibliography

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