Csehbánya Formation

The Csehbánya Formation is a geological formation in the Transdanubian Mountains of Veszprém County, Hungary. The formation dates to the Late Santonian (around 85 million years ago) of the Late Cretaceous. It represents a floodplain environment as opposed to the swampy lacustrine environment of the simultaneous Ajka Coal Formation, though there is complete overlap in terms of fauna. It underlies the Jákó Marl formation, and laterally transitions to the Ajka Coal Formation.[1]

Csehbánya Formation Stratigraphic range: Late Santonian ~85–84 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Type	Geological formation
Underlies	Jákó Marl Formation, localized unconformity with Eocene Iharkút Conglomerate present in some areas
Overlies	Unconformity with Upper Triassic Main Dolomite Formation and Upper Cretaceous Nagytárkány Bauxite Formation
Area	Transdanubian Mountains
Thickness	Varies, but up to 100–150 m (330–490 ft)
Lithology
Primary	Siltstone, sandstone conglomerate
Other	Claystone
Location
Coordinates	47.24°N 17.64°E
Approximate paleocoordinates	31.0°N 18.6°E
Region	Europe
Country	Hungary
Type section
Named for	Csehbánya, Hungary
Csehbánya Formation (Hungary)

Stratigraphy of the Iharkút locality

Geology

The lithology of the unit is a cyclic variation of conglomerate, sandstone, variegated siltstone, clay and marl layers with some sporadic thin coal seams.[2] It is uncomfortably overlies the Late Triassic Main Dolomite Formation, which has deposits of the Upper Cretaceous Nagytárkány Bauxite Formation within deep karstic sinkholes in the formation. There is a basal conglomerate of dolomite clasts at the base of the Csehbánya formation. The main exposed portion of the formation is called the Iharkút locality, which is a disused bauxite quarry. At this location due to Paleogene uplift, it is uncomfortably overlain by the Lutetian Ikharkút Conglomerate. In the upper levels of the formation, there are sandstone lens beds present, which represent channel bodies. These are indicative of an anastomosing fluvial system. The exposure at this locality is between 100–150 m. Most of the fossils are found within the SZ-6 site at the locality, which is interpreted as a lag channel deposit

Invertebrate paleofauna

Amber is known from both the Ajka Coal and Csehbánya Formations, and is commonly referred to as ajkait. However most of the arthropod inclusions in these are undescribed, only being shown in photographs,[3] With only two species of Ceratopogonids (biting midges) in the extant genus Leptoconops and the extinct genus Adelohelea being described.[4] A list of known taxa is given below.

Invertebrates
Genus	Species	Location	Stratigraphic position	Abundance	Notes	Images
Adelohelea	A. magyarica				Biting midge
Leptoconops	L. clava				Biting midge, genus currently extant
Coleoptera	Indeterminate
Diptera	Indeterminate
Hymenoptera	Indeterminate
Nematocera	Indeterminate

Vertebrate paleofauna

Various fossils from the Csehbánya Formation

Fishes, amphibians, turtles, squamates, crocodilians, dinosaurs,[5] birds and pterosaurs present in Veszprém, Hungary, near the village of Németbánya in the Iharkút locality, an open-pit bauxite mine.[6][7] Other finds include Abelisauridae indet.,[8] Rhabdodontidae indet.,[7] Tetanurae indet.[8] Coprolites[9] and eggshells[10] are also known from the locality.

Fish

Fish[11]
Genus	Species	Location	Stratigraphic position	Abundance	Notes	Images
Atractosteus	Indeterminate	Iharkút locality		"Jaw fragments, teeth, scales, vertebrae"	Gar, genus extant
Coelodus	Indeterminate			Possible dentary/premaxilla, vomers, prearticulars, teeth and possible scales[12]	Pycnodontiform
Vidalamiinae	Indeterminate			"Two vertebrae"
Amiidae	Indeterminate			A left anterior ceratohyal and a vertebra
Elopiformes	Indeterminate			13 vertebrae
Ellimmichthyiformes	Indeterminate			At least two distinct taxa represented by four and one vertebrae	Clupeimorph
cf. Salmoniformes	Indeterminate			two vertebrae
Acanthomorpha	Indeterminate			Three vertebrae and 18 fin spines
Teleostei	Indeterminate			Teeth, vertebrae and cycloid scales
Actinopterygii	Indeterminate			9 distinct teeth morphotypes and some teeth bearing elements

Amphibians

Amphibians
Genus	Species	Location	Stratigraphic position	Abundance	Notes	Images
Albanerpeton[13]	Indeterminate	Iharkút locality		Skull and jaw elements	Albanerpetonid
Bakonybatrachus[14]	B. fedori	Iharkút locality		Pelvic elements	Discoglossid frog
Hungarobatrachus[15]	H. szukacsi	Iharkút locality		Pelvic elements	Advanced frog
Palaeobatrachidae	Indeterminate	Iharkút locality		Postcranial remains
Pelobatidae	Indeterminate	Iharkút locality		Postcranial remains

Squamates

Squamates
Genus	Species	Location	Stratigraphic position	Abundance	Notes	Images
Bicuspidon	B. aff. hatzegiensis[16]			Fragmentary mandibles, maxillae	Polyglyphanodontid
Chromatogenys[17]	C. tiliquoides			Partial right mandible	Scincomorph
Distortodon[18]	D. rhomboideus			Dentaries, maxilla	Polyglyphanodontid
Pannoniasaurus[19]	P. inexpectatus			Partial skeleton	Mosasaur, also known from Ajka Coal Formation[1]
Pelsochamops[20]	P. infrequens			Fragmentary dentary, dentary fragments	Chamopsiid
Scincomorpha[21]	Indeterminate			Fragmentary dentaries	At least 3 distinct taxa, 4 mentioned in paper, but unsure if this counts Chromatogenys

Crocodyliformes

Crocodyliformes of the Csehbánya Formation
Genus	Species	Location	Stratigraphic position	Abundance	Notes	Images
Iharkutosuchus[22]	I. makadii			"Complete and partial skulls, mandibles, various cranial elements, teeth"	Hylaeochampsid
Doratodon[23]	D. carcharidens			"Teeth, Jaw fragment"
?Theriosuchus	Indeterminate			"Teeth, cranial elements"
?Allodaposuchus	Indeterminate			"Teeth, jaw fragments, cranial elements"

Turtles

Turtles of the Csehbánya Formation
Genus	Species	Location	Stratigraphic position	Abundance	Notes	Images
Foxemys	F. trabanti			"Complete and partial skulls, mandibles, vertebrae, pectoral and pelvic girdle elements, limb bones, plastron and carapax fragments"
Kallokibotion	Indeterminate			Shell fragments
Dortokidae	Indeterminate			Shell fragments

Pterosaurs

Pterosaurs of the Csehbánya Formation
Genus	Species	Location	Stratigraphic position	Abundance	Notes	Images
Bakonydraco [24]	B. galaczi	Veszprém		"Premaxilla, complete mandible, 56 mandibular symphyses"	Tapejarid
Azdarchidae	Indeterminate			"Cervical vertebrae, pelvic girdle elements, limb bones"
Pterodactyloidea	Indeterminate			"3 mandibular symphyses"

Non-avian dinosaurs

Dinosaurs of the Csehbánya Formation
Genus	Species	Location	Stratigraphic position	Abundance	Notes	Images
Ajkaceratops[25]	A. kozmai[25]			Fused premaxillae and rostral bones, with fragments of the maxillae, four predentaries.[25] Referred teeth.[26]	Bagaceratopsid ceratopsian
Hungarosaurus[27]	H. tormai	Veszprém		Several partial skeletons	Struthiosaurine nodosaur
Pneumatoraptor[8]	P. fodori	Veszprém		Single left scapulocoracoid	Paravian
Mochlodon	M. vorosi[28]			Partial skull and postcrania	Rhabdodontid
Struthiosaurus	Indeterminate			Humerus[29] and partial hip, and pelvic armor elements.[30]	Struthiosaurine nodosaur
Paraves	Indeterminate			"Teeth, caudals, limb bones"
Abelisauridae	Indeterminate			Femur[31] and pedal ungual phalanx[8]
Tetanurae	Indeterminate			More than 50 teeth[8]
Sauropoda[32]	Indeterminate			Single tooth

Birds

Birds of the Csehbánya Formation
Genus	Species	Location	Stratigraphic position	Abundance	Notes	Images
Bauxitornis[33]	B. mindszentyae			Single left metatarsus	An avisaurid enantiornithine
Enantornithine	Indeterminate			Limb bones

See also

• List of dinosaur-bearing rock formations
• List of fossiliferous stratigraphic units in Hungary

References

1. Ősi, Attila; Bodor, Emese Réka; Makádi, László; Rabi, Márton (2016). "Vertebrate remains from the Upper Cretaceous (Santonian) Ajka Coal Formation, western Hungary" (PDF). Cretaceous Research. 57: 228–238. doi:10.1016/j.cretres.2015.04.014. ISSN 0195-6671.
2. Botfalvai, Gábor; Haas, János; Bodor, Emese Réka; Mindszenty, Andrea; Ősi, Attila (2016). "Facies architecture and palaeoenvironmental implications of the upper Cretaceous (Santonian) Csehbánya formation at the Iharkút vertebrate locality (Bakony Mountains, Northwestern Hungary)" (PDF). Palaeogeography, Palaeoclimatology, Palaeoecology. 441: 659–678. doi:10.1016/j.palaeo.2015.10.018. ISSN 0031-0182.
3. "Research of Cretaceous ambers and their inclusions: Cretaceous ambers from Hungary". Magyar Dinoszaurusz. Retrieved 21 April 2018.
4. Borkent, Art (1997). "Upper and Lower Cretaceous biting midges (Ceratopogonidae: Diptera) from Hungarian and Austrian amber and the Koonwarra Fossil Bed of Australia". Stuttgarter Beiträge zur Naturkunde. Serie B (Geologie und Paläontologie). 249: 1–10.
5. Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Cretaceous, Europe)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 588-593. ISBN 0-520-24209-2.
6. Makádi, L., Botfalvai, G., Ősi, A. 2006: Egy késő-kréta kontinentális gerinces fauna a Bakonyból: halak, kétéltűek, teknősök, gyíkok. Földtani Közlöny 136/4, pp. 487-502.
7. Ősi, A. & Rabi, M., 2006. Egy késő-kréta kontinentális gerinces fauna a Bakonyból II.: krokodilok, dinoszauruszok, pteroszauruszok és madarak (The Late Cretaceous continental vertebrate fauna from the Bakony Mountains II: crocodiles, dinosaurs (Theropoda, Aves, Ornithischia), pterosaurs). Földtani Közlöny, 136, 4, 503–526.
8. Ősi, A.; Apesteguía, S.M; Kowalewski, M. (2010). "Non-avian theropod dinosaurs from the early Late Cretaceous of Central Europe". Cretaceous Research. 31: 304–320. doi:10.1016/j.cretres.2010.01.001.
9. Segesdi, Martin; Botfalvai, Gábor; Bodor, Emese Réka; Ősi, Attila; Buczkó, Krisztina; Dallos, Zsolt; Tokai, Richárd; Földes, Tamás (June 2017). "First report on vertebrate coprolites from the Upper Cretaceous (Santonian) Csehbánya Formation of Iharkút, Hungary". Cretaceous Research. 74: 87–99. doi:10.1016/j.cretres.2017.02.010. ISSN 0195-6671.
10. Prondvai, Edina; Botfalvai, Gábor; Stein, Koen; Szentesi, Zoltán; Ősi, Attila (March 2017). "Collection of the thinnest: A unique eggshell assemblage from the Late Cretaceous vertebrate locality of Iharkút (Hungary)". Central European Geology. 60 (1): 73–133. doi:10.1556/24.60.2017.004. ISSN 1788-2281.
11. Szabó, Márton; Ősi, Attila (September 2017). "The continental fish fauna of the Late Cretaceous (Santonian) Iharkút locality (Bakony Mountains, Hungary)". Central European Geology. 60 (2): 230–287. doi:10.1556/24.60.2017.009. ISSN 1788-2281.
12. Szabó, Márton; Gulyás, Péter; Ősi, Attila (April 2016). "Late Cretaceous (Santonian) pycnodontid (Actinopterygii, Pycnodontidae) remains from the freshwater deposits of the Csehbánya Formation, (Iharkút, Bakony Mountains, Hungary)". Annales de Paléontologie. 102 (2): 123–134. doi:10.1016/j.annpal.2016.04.001. ISSN 0753-3969.
13. Szentesi, Zoltán; Gardner, James D.; Venczel, Márton (March 2013). "Albanerpetontid amphibians from the Late Cretaceous (Santonian) of Iharkút, Hungary, with remarks on regional differences in Late Cretaceous Laurasian amphibian assemblages". Canadian Journal of Earth Sciences. 50 (3): 268–281. Bibcode:2013CaJES..50..268S. doi:10.1139/e2012-024. ISSN 0008-4077.
14. Szentesi, Zoltán; Venczel, Márton (April 2012). "A new discoglossid frog from the Upper Cretaceous (Santonian) of Hungary". Cretaceous Research. 34: 327–333. doi:10.1016/j.cretres.2011.11.012. ISSN 0195-6671.
15. Zoltán Szentesi and Márton Venczel (2010). "An advanced anuran from the Late Cretaceous (Santonian) of Hungary" (PDF). Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen. 256 (3): 291–302. doi:10.1127/0077-7749/2010/0054.
16. Makádi, László (December 2006). "Bicuspidon aff. hatzegiensis (Squamata: Scincomorpha: Teiidae) from the Upper Cretaceous Csehbánya Formation (Hungary, Bakony Mts)" (PDF). Acta Geologica Hungarica. 49 (4): 373–385. doi:10.1556/ageol.49.2006.4.5. ISSN 0236-5278.
17. Makádi, László; Nydam, Randall L. (2014-12-23). "A new durophagous scincomorphan lizard genus from the Late Cretaceous Iharkút locality (Hungary, Bakony Mts)" (PDF). Paläontologische Zeitschrift. 89 (4): 925–941. doi:10.1007/s12542-014-0253-1. ISSN 0031-0220.
18. Makádi, László (November 2013). "A new polyglyphanodontine lizard (Squamata: Borioteiioidea) from the Late Cretaceous Iharkút locality (Santonian, Hungary)" (PDF). Cretaceous Research. 46: 166–176. doi:10.1016/j.cretres.2013.08.001. ISSN 0195-6671.
19. Makádi, László; Caldwell, Michael W.; Ősi, Attila (2012-12-19). "The First Freshwater Mosasauroid (Upper Cretaceous, Hungary) and a New Clade of Basal Mosasauroids". PLOS ONE. 7 (12): e51781. Bibcode:2012PLoSO...751781M. doi:10.1371/journal.pone.0051781. ISSN 1932-6203. PMC 3526648. PMID 23284766.
20. Makádi, László (July 2013). "The first known chamopsiid lizard (Squamata) from the Upper Cretaceous of Europe (Csehbánya Formation; Hungary, Bakony Mts)" (PDF). Annales de Paléontologie. 99 (3): 261–274. doi:10.1016/j.annpal.2013.07.002. ISSN 0753-3969.
21. Botfalvai, Gábor; Ősi, Attila; Mindszenty, Andrea (January 2015). "Taphonomic and paleoecologic investigations of the Late Cretaceous (Santonian) Iharkút vertebrate assemblage (Bakony Mts, Northwestern Hungary)" (PDF). Palaeogeography, Palaeoclimatology, Palaeoecology. 417: 379–405. doi:10.1016/j.palaeo.2014.09.032. ISSN 0031-0182.
22. Ősi, Attila; Clark, James M.; Weishampel, David B. (2007-02-01). "First report on a new basal eusuchian crocodyliform with multicusped teeth from the Upper Cretaceous (Santonian) of Hungary". Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen. 243 (2): 169–177. doi:10.1127/0077-7749/2007/0243-0169. ISSN 0077-7749.
23. Rabi, Márton; Sebők, Nóra (October 2015). "A revised Eurogondwana model: Late Cretaceous notosuchian crocodyliforms and other vertebrate taxa suggest the retention of episodic faunal links between Europe and Gondwana during most of the Cretaceous". Gondwana Research. 28 (3): 1197–1211. Bibcode:2015GondR..28.1197R. doi:10.1016/j.gr.2014.09.015. ISSN 1342-937X.
24. Ösi, Attila; Weishampel, David B.; Jianu, Coralia M. (2005). "First evidence of azhdarchid pterosaurs from the Late Cretaceous of Hungary". Acta Palaeontologica Polonica. 50 (4): 777–787.
25. Ősi, A.; Butler, R.J.; Weishampel, David B. (2010). "A Late Cretaceous ceratopsian dinosaur from Europe with Asian affinities". Nature. 465 (7297): 466–468. Bibcode:2010Natur.465..466O. doi:10.1038/nature09019. PMID 20505726.
26. Virág, Attila; Ősi, Attila (2017-04-27). "Morphometry, Microstructure, and Wear Pattern of Neornithischian Dinosaur Teeth From the Upper Cretaceous Iharkút Locality (Hungary)" (PDF). The Anatomical Record. 300 (8): 1439–1463. doi:10.1002/ar.23592. ISSN 1932-8486. PMID 28371453.
27. Ösi, Attila (2005). "Hungarosaurus tormai, a new ankylosaur (Dinosauria) from the Upper Cretaceous of Hungary". Journal of Vertebrate Paleontology. 25 (2): 370–383. doi:10.1671/0272-4634(2005)025[0370:htanad]2.0.co;2.
28. Ősi, A.; Prondvai, E.; Butler, R.; Weishampel, D. B. (2012). Evans, Alistair Robert (ed.). "Phylogeny, Histology and Inferred Body Size Evolution in a New Rhabdodontid Dinosaur from the Late Cretaceous of Hungary". PLoS ONE. 7 (9): e44318. Bibcode:2012PLoSO...744318O. doi:10.1371/journal.pone.0044318. PMC 3448614. PMID 23028518.
29. Ősi, Attila; Prondvai, Edina (August 2013). "Sympatry of two ankylosaurs (Hungarosaurus and cf. Struthiosaurus) in the Santonian of Hungary" (PDF). Cretaceous Research. 44: 58–63. doi:10.1016/j.cretres.2013.03.006. ISSN 0195-6671.
30. Ősi, Attila; Pereda-Suberbiola, Xabier (July 2017). "Notes on the pelvic armor of European ankylosaurs (Dinosauria: Ornithischia)" (PDF). Cretaceous Research. 75: 11–22. doi:10.1016/j.cretres.2017.03.007. ISSN 0195-6671.
31. Ősi, Attila; Buffetaut, Eric (January 2011). "Additional non-avian theropod and bird remains from the early Late Cretaceous (Santonian) of Hungary and a review of the European abelisauroid record" (PDF). Annales de Paléontologie. 97 (1–2): 35–49. doi:10.1016/j.annpal.2011.07.001. ISSN 0753-3969.
32. Ősi, Attila; Csiki-Sava, Zoltán; Prondvai, Edina (2017-06-12). "A Sauropod Tooth from the Santonian of Hungary and the European Late Cretaceous 'Sauropod Hiatus'". Scientific Reports. 7 (1): 3261. Bibcode:2017NatSR...7.3261O. doi:10.1038/s41598-017-03602-2. ISSN 2045-2322. PMC 5468229. PMID 28607394.
33. Gareth J. Dyke, Attila Ősi (2010). "A review of Late Cretaceous fossil birds from Hungary". Geological Journal. 45 (4): 434–444. doi:10.1002/gj.1209.CS1 maint: uses authors parameter (link)