| Ariyalaur Group | |
|---|---|
| Stratigraphic range: Late Cretaceous to Palaeogene (Paleocene) (Campanian to Danian) ~ | |
| Type | Geological group |
| Sub-units | Sillakkudi formation, Kallakurichi Formation, Ottakovil formation, Kallamedu Formation |
| Underlies | Niniyur Formation |
| Overlies | Anaipadi Formation, Trichinopoly Group |
| Location | |
| Country |  India |
  Ariyalur Group (India)  Ariyalur Group (Tamil Nadu) | |
The Ariyalaur Group is a geological group in Tamil Nadu in Southern India. [1] [2]
Color key
| Notes Uncertain or tentative taxa are in small text; |
| Dinosaurs from the Ariyalaur group | |||||
|---|---|---|---|---|---|
| Genus | Species | Material | Notes | Member | Images |
| Abelisauridae indet. [3] | "Disassociated remains" and teeth. | Kallamedu formation | |||
| Carnosauria indet.? [4] | "Fragmentary remains". | Carnosauria was often used as a wastebasket taxon. | Kallamedu formation | ||
| Troodontidae indet. [3] | One isolated tooth (DUGF/52). | Kallamedu formation | |||
| Bruhathkayosaurus [4] [5] | B. matleyi | ilium and ischium, femur, tibia, radius and part of a vertebra (specifically a platycoelous caudal centrum). Remains no longer exist. | Initially described as a Theropod, it was reclassified as a Titanosaur. | Kallamedu formation |  |
| Sauropoda | Indeterminate. [6] [7] | "Fragmentary remains". | Kallamedu formation | ||
| Titanosauria | Indeterminate. [8] | Solitary egg. | Kallamedu formation | ||
| Titanosauria | Indeterminate. [9] | Ten large sauropod bones, some of which could be identified as a humerus or femur, proximal end of a femur and scapula. All the bones pertain to the limbs. | Similar in size to Bruhathkayosaurus. [5] | Kallamedu formation | |
| Fusioolithus [8] | F. baghensis | Dinosaur eggs. | Kallamedu formation | ||
| ?Camarasauridae [10] | Indeterminate. | Vertebrae. | Camarasaurids are not known from the cretaceous. | Kallamedu formation | |
| ?Stegosauria [11] | Indeterminate. | Misinterpreted sauropod bone. | Other more plausible Stegosaur material is known from Cretaceous India. | Kallamedu formation | |
| Sauropoda | Sauropoda indet. [5] | "Scant remains". | |||
| Stegosauria | Stegosauria indet. [5] | ||||
| Theropoda | Theropoda indet. [5] | "Scant remains". | |||
| Theropoda [12] | indet. | A Theropod. | Kallankurichchi formation | ||
| ? Titanosaurus [12] | T. indicus | A dubious genus of titanosaurian sauropod. | Kallakurichi Formation |  | |
| Megaloolithus [13] | M. cylindricus | Fossilised eggs. | A Sauropod Oogenus. | Kallakurichi Formation |  The holotype of Sanajeh preserved with Megaloolithus |
| Stegosauridae [12] | Stegosauridae indet | A Stegosaurid. | Kallakurichi Formation | ||
| Molluscs from the Ariyalaur group | |||||
|---|---|---|---|---|---|
| Genus | Species | Material | Notes | Member | Images |
| Inoceramus [5] | I. sp. | Sillakkudi formation |  | ||
| Karapadites [5] | K. karapadense | Sillakkudi formation | |||
| Inoceramus [14] | I. bulbus | A clam. | Kallakurichi formation | ||
| I. tamulicus | Kallakurichi formation | ||||
| Pycnodonta [14] | P. vesicularis | A clam. | Kallakurichi formation | ||
| Ostrea (Alectryonia) [14] | sp. | A clam. | Kallakurichi formation |  | |
| Anisomyon [14] | A. indicus | A snail. | Kallakurichi formation |  | |
| Foraminiferas from the Ariyalaur group | |||||
|---|---|---|---|---|---|
| Genus | Species | Material | Notes | Images | |
| Globotruncana | G. arca [5] | Sillakkudi formation |  | ||
| G. ventricosa [5] | Sillakkudi formation | ||||
| G. elevata [5] | Sillakkudi formation | ||||
| Sea Urchins from the Ariyalaur group | |||||
|---|---|---|---|---|---|
| Genus | Species | Material | Member | Notes | Images |
| Hemipneustes | H. compressus [15] | Kallakurichi Formation |  | ||
| Rhynchonellatans from the Ariyalaur group | |||||
|---|---|---|---|---|---|
| Genus | Species | Material | Notes | Member | Images |
| Rectithyris | R. subdepressa [14] | Kallakurichi Formation | |||
| Rhynchonella | R. sp. [14] | Kallakurichi Formation |  | ||
| Brachiopods from the Ariyalaur group | |||||
|---|---|---|---|---|---|
| Genus | Species | Material | Notes | Member | Images |
| Gyrodina | G. globosa [14] | Kallakurichi Formation | |||
| Neobulimina | N. sp. [14] | Kallakurichi Formation | |||
| Arthropods from the Ariyalur group | |||||
|---|---|---|---|---|---|
| Genus | Species | Material | Notes | Member | Images |
| Thalassinoides | T. sp. [16] | An ichnofossil made by decapod crustaceans, or fish | Ottakovil Formation |  | |
| Ophiomorpha | O. sp. [16] | Made by burrowing arthropods | Ottakovil Formation |  | |
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