Irdin Manha Formation
Irdin Manha Formation
Stratigraphic range : Eocene
Location
Coordinates 43°42′N 112°00′E/43.7°N 112.0°E/ 43.7; 112.0
Approximate paleocoordinates 45°12′N 105°42′E/45.2°N 105.7°E/ 45.2; 105.7
The Irdin Manha Formation is a geological formation from the Eocene located in Inner Mongolia , China, a few kilometres south of the Mongolian border.
Fossil content 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.Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Mammals U.S. paleontologists Henry Fairfield Osborn and Roy C. Andrews discovered two premolars on the site in 1923, and assigned the specimen to the new genus Eudinoceras because he believed it to be related to "Dinoceras Uintatherium ). Within a decade, however, as more complete specimens were recovered, the animal was identified as a Mongolian relative to the North American pantodont Coryphodon Andrewsarchus
Artiodactyls Artiodactyls reported from the Irdin Manha FormationGenus Species Presence Material Notes Images Achaenodontidae ?An incomplete upper tooth (AMNH 20136). Doubtfully assigned to the family. Cf. Archaeomeryx , gen indet. Fragment of lower jaw (AMNH 20173). A traguliform . Andrewsarchus A. mongoliensis Around Telegraph Line Camp. A large skull. A relative of entelodonts formerly thought to be a mesonychid . Erlianhyus E. primitivus Irdin Manha, Erlian Basin, Nei Mongol. A right upper maxilla with P3–M3 (IVPP V 28275). A basal artiodactyl. Gobiohyus G. orientalis Telegraph Line Camp. Jaw elements. A helohyid also found in the Ulan Shireh Formation. G. pressidens Telegraph Line Camp. Partial right rami . A helohyid . G. robustus Telegraph Line Camp. Left ramus (AMNH 20246). A helohyid . Obotherium O. parvum Irdin Manha, Erlian Basin, Nei Mongol. Teeth and lower jaws A tapirulid.
Cimolestans Cimolestans reported from the Irdin Manha FormationGenus Species Presence Material Notes Images Eudinoceras E. mongoliensis 2 premolars & jaw elements. A coryphodontid .
Dinoceratans Dinoceratans reported from the Irdin Manha FormationGenus Species Presence Material Notes Images Gobiatherium G. mirificum 25 miles southwest from Iren Dabasu. Skull, jaws & limb elements. An uintatheriid .
Ferae Ferae reported from the Irdin Manha FormationGenus Species Presence Material Notes Images Miacis M. invictus Isolated upper molar (AMNH 20137). A miacid . Propterodon P. irdinensis Jaw fragments. A hyaenodontid . Sarkastodon S. mongoliensis About 25 miles southwest of Iren Dabasu. Skull & jaws. An oxyaenid .
Glires Glires reported from the Irdin Manha FormationGenus Species Presence Material Notes Images Advenimus A. burkei Near Camp Margetts. Jaw elements. A ctenodactyloid rodent. Asiomys A. dawsoni Huheboerhe. Fragment of right calcaneus (IVPP V24417). An ischyromyid rodent. Erenlagus E. anielae Huheboerhe. Teeth. A stem-lagomorph . Gomphos G. shevyrevae Huheboerhe escarpment. Teeth & foot elements. A mimotonid. Ischyromyidae genus indet. Species A Irdin Manha escarpment. Right calcaneus (IVPP V24416). Relatively large ischyromyid rodent, calcaneus comparable in size to that of a coypu or Asiatic brush-tailed porcupine . Species B Daoteyin Obo. Right calcaneus (IVPP V24418). Large ischyromyid rodent with calcaneus matching in length that of a coypu & similar in structure to that of Paramys Mimolagus M. aurorae Irdin Manha escarpment. Teeth & foot elements. A large mimotonid. Pappocricetodon P. neimongolensis Huheboerhe. Teeth. A cricetid rodent. P. cf. P. zhongtiaensis Huheboerhe. A left molar . A cricetid rodent. P. sp.Huheboerhe. A right molar. A cricetid rodent. Paramyidae Paramyid spp. Teeth & jaws. 3 sizes of paramyid rodents, possibly different species. ?Paramyid sp. Left jaw (AMNH 80801). Possible small paramyid rodent. Simplicimys S. bellus Huheboerhe. Teeth. A ctenodactyloid rodent also known from the Arshanto Formation. Strenulagus S. solaris Irdin Manha and Huheboerhe localities. Isolated cheek teeth, fragmentary upper incisors (dI2) and postcranial elements. A stem-lagomorph also known from the Khaychin Formation. Tamquammys T. fractus Huheboerhe. Right maxilla (V17798). A ctenodactyloid rodent. T. wilsoni Teeth. A ctenodactyloid rodent also known from the Arshanto & Nomogen formations. Yongshengomys Y. extensus Huheboerhe. Teeth. A ctenodactyloid rodent. Yuomys Y. huheboerhensis Huheboerhe. Teeth. A ctenodactyloid rodent. Y. sp. AHuheboerhe. A right molar (V17805). A ctenodactyloid rodent. Y. sp. BHuheboerhe. A right molar (V17806). A ctenodactyloid rodent. Y. sp. CHuheboerhe. A right molar (V17807). A ctenodactyloid rodent.
Mesonychians Mesonychians reported from the Irdin Manha FormationGenus Species Presence Material Notes Images Hapalodectes ?H. auctus An upper molar or possibly premolar (AMNH 20130). A hapalodectid . H. serus Around Telegraph Line Camp. Lower cheek tooth (AMNH 20172). A hapalodectid . Harpagolestes H. leei Huheboerhe & Daoteyin Obo. Tooth elements. A mesonychid . Mesonychidae Gen. indet. AMNH 20132. About the size of Harpagolestes uintensis Gen. indet. Isolated tooth (AMNH 20133). About the size of Synoplotherium lanius Mongolonyx M. dolichognathus 7 miles west of Camp Margetts. Jaw elements. A large mesonychid .
Panperissodactyla Panperissodactylas reported from the Irdin Manha FormationGenus Species Presence Material Notes Images Caenolophus C. proficiens Lower jaw & isolated teeth. A rhinocerotoid . Cooperia C. totadentata Telegraph Line Camp, 23 miles southeast of Iren Dabasu. Front of skull (AMNH 20116). Generic name preoccupied, renamed Forstercooperia Desmatotherium D. fissum Upper jaw fragment. A helaletid . D. mongoliense Irdin Manha escarpment, Duheminboerhe, Huheboerhe & Chaganboerhe. Parts of 10 individuals. A helaletid also found in the Mergen Formation. Forstercooperia F. totadentata Telegraph Line Camp, 23 miles southeast of Iren Dabasu. Front of skull (AMNH 20116). A paraceratheriid , originally named Cooperia . F. ulanshirehensis Irdin Manha site. Jaw elements. A paraceratheriid also known from the Ulan Shireh Formation. Gnathotitan G. berkeyi Irdin Manha. Jaw elements. A brontothere . Lophialetes L. expeditus Jaw elements. A lophialetid. L. minutus Upper molar. A lophialetid. Metatelmatherium M. cristatum Camp Margetts. Skull & lower jaw (AMNH 26411). A brontothere . M. parvum Irdin Manha. Fragment of left lower jaw (AMNH 20168). A brontothere . Microtitan M. mongoliensis Jaw elements. A brontothere . Pappaceras P. confluens Upper gray clays & Camp Margetts area. Skull & jaw elements. A paraceratheriid . Paracolodon P. fissus Duheminboerhe & Daoteyin Obo. Skull elements & teeth. A helaletid . Protitan P. bellus Spring Camp, East Mesa, Shara Murun region. Palatal side of skull (AMNH 26104). A brontothere . P. grangeri Skull elements. A brontothere . P. minor Camp Margetts. Skull elements. A brontothere . P. obliquidens Irdin Manha. Part of left maxilla (AMNH 20125). A brontothere . P. robustus Irdin Manha. Jaw elements & teeth. A brontothere . Rostriamynodon R. grangeri East of Camp Margetts. Complete skull & mandible (AMNH 107635). An amynodontid . Teleolophus T. medius Teeth & jaws.
Primates Primates reported from the Irdin Manha FormationGenus Species Presence Material Notes Images Tarkops T. mckennai Huheboerhe. Incomplete left lower jaw (IVPP V16424). An omomyid .
Reptiles Birds Birds reported from the Irdin Manha FormationGenus Species Presence Material Notes Images Buteoninae Chimney Butte. Left coracoid (AMNH FR 2941). Specimen reassigned to Eogrus? sp. Eogrus E. aeola Chimney Butte. Right metatarsus (AMNH 2936). An eogruid . E.? sp.Chimney Butte. Left coracoid (AMNH FR 2941). Formerly thought to represent a buteonine , now thought to be an eogruid . Telecrex T. grangeri Chimney Butte, Shara Murun region. An incomplete right femur (AMNH 2942). A guineafowl , formerly thought to be a rail .
Crocodilians Crocodilians reported from the Irdin Manha FormationGenus Species Presence Material Notes Images Asiatosuchus A. grangeri 25 miles southwest of Iren Dabasu. Portions of at least 2 individuals. A crocodyloid .
Testudines Testudines reported from the Irdin Manha FormationGenus Species Presence Material Notes Images "Adocus " "A". orientalis Telegraph Line Camp. Anterior half of plastron (AMNH 6356). An adocid . Amyda ?A.? johnsoni Telegraph Line Camp. Two-thirds of a carapace (AMNH 6357) & many carapace fragments (AMNH 6359). A softshell turtle . Trionychidae Indeterminate Telegraph Line Camp. Several kinds of sculptured fragments (AMNH 6360). Remains of softshell turtles.
Fish Fish reported from the Irdin Manha FormationGenus Species Presence Material Notes Images Pappichthys P. mongoliensis Telegraph Line Camp. Vertebrae. Specimens now believed to represent Siluriformes . Siluriformes Indeterminate Telegraph Line Camp, Chahar Province . 5 vertebrae (AMNH 8535). A catfish likely related to ictalurids . Formerly assigned to Pappichthys mongoliensis .
See also