Tlayúa Formation

The Tlayúa Formation is an Cretaceous Konservat-Lagerstätte near Tepexi de Rodríguez, Puebla, Central Mexico.^[1] It consists of three members (Lower, Middle and Upper), spanning the lower Albian of the Early Cretaceous to the lower Cenomanian of the Late Cretaceous. It consists of a series of limestone quarries that preserve lagoonal palaeoenvironments, such as a shelf lagoon, a shallow lagoon surrounded by a penneplain, and a tidal flat. It is notable for preserving high quantities of vertebrate and invertebrate fossils, and is thus considered a Lagerstätte.

Tlayúa Formation
Stratigraphic range: Albian–Cenomanian PreꞒ Ꞓ O S D C P T J K Pg N
Cipactlichthys scutatus, one of the fossil fish from Tlayúa Formation
Type	Geological formation
Sub-units	Lower, Middle and Upper Members
Underlies	Unconformity with Eocene-Oligocene Pie de Vaca Formation
Overlies	Orizaba Formation
Thickness	Lower: 50 m Middle: 35 m Upper: 40 m
Lithology
Primary	Limestone
Other	Mudstone
Location
Coordinates	19.1°N 98.2°W / 19.1; -98.2
Approximate paleocoordinates	17.1°N 61.6°W / 17.1; -61.6
Region	Puebla
Country	Mexico
Type section
Named for	Tlayúa Quarry
Tlayúa Formation (Mexico)

Description

The Tlayúa Formation was first described by Jerjes Pantoja-Alor in 1992.^[2] It is located in the Tlayúa ravine, which itself lies in the southern portion of Puebla, Central Mexico, near Tepexi de Rodríguez,^[1] and consists of a series of limestone quarries that has seen commercial use for decades.^[3]

Stratigraphy

The Tlayúa Formation consists of two stratigraphic units (Tlayúa and Barranca Abuelo)^[4] and three members. The Lower Member is lower Albian in age. It consists of bioturbated limestones, and is characterised by the presence of the non-rudist bivalve Chondrodonta and the rudist bivalve Toucasia polygyra. The Middle Member, corresponding to the Tlayúa Quarry, is the most fossiliferous.^[3] Its age has been difficult to ascertain, as the foraminiferan Spiroloculina cretacea is known exclusively from lower Cenomanian strata,^[5] though it has since been determined to be Upper Albian.^[3] The Middle Member consists of fine-grained lithographic limestones, interspersed with hematitic layers that preserve its vertebrate fauna. The Upper Member is Cenomanian in age, and consists of a sequence of dolomites. It is characterised by the presence of the miliolid foraminiferan Dicyclina schlumbergi.^[3]

Depositional environments

The depositional environment of the Tlayúa Formation was likely a shallow, coastal lagoon,^[6] with some freshwater influence, as indicated by the presence of crocodilian and turtle fossils.^[6][7] The Lower Member of the Tlayúa Formation represents a carbonate environment which apparently had stressed biodiversity.^[4] The depositional environment of the Middle Member was likely arid for much of the year, with the exception of seasonal rains and storms.^[7] The Upper Member likely represents a tidal flat.^[4] The Tlayúa Formation may have been part of an island, though a connection to the North American mainland cannot be discounted.^[7]

Paleobiota

The formation contains a diverse array of vertebrate and invertebrate fossils. For this reason, it is considered a Konservat-Lagerstätte.^[4][8] About 70% of the macrofossils are osteichthyan fish.^[9] Other vertebrates include chelonians, pterosaurs, lepidosaurs, and crocodiles.^[10] Cyanobacteria, foraminifera, algae, gymnosperms, sponges, cnidarians, annelids, gastropods, ammonites, bivalves, arachnids, insects, isopods, anomurans, brachyurans, crinoids, echinoids, holothuroids, stelleroids, and ophiuroids, have also been recovered from the Tlayúa Formation.^[10][11][12]

Archelosaurs

The remains of several indeterminate archelosaur taxa have been recovered from the Tlayúa Formation. Indeterminate crocodilians and turtles have been identified.^[6][7] Partial, articulated wings of an unidentified pterosaur have been discovered from the formation. Though tentatively assigned to Pteranodon sp. and Nyctosaurus sp. in 2008,^[13] they likely represent either an early azhdarchoid or an indeterminate ornithocheiromorph.^[14]

Lepidosaurs

Genus	Species	Material	Notes
Huehuecuetzpalli[15]	H. mixtecus	Near-complete specimens of an adult and a juvenile	A primitive lizard
Pamizinsaurus[16]	P. tlayuaensis	A single, crushed skull of a juvenile	An osteoderm-covered sphenodontian
Ankylosphenodon[17]	A. pachyostosus	Front half of a partial skeleton	An aquatic sphenodontian
Tepexisaurus[18]	T. tepexii	Near-complete skeleton, minus the tail	A basal scincomorph

Fish

Mainly after González-Rodríguez (2016)^[19] and Applegate et al. (2006)^[3]

• Araripichthys webri
• Armigatus carrenoae
• Armigatus felixi
• Axelrodichthys cf. araripensis
• Cipactlichthys scutatus
• Epaelops martinezi
• Macrosemiocotzus americanus
• Michin csernai
• Notagogus novomundi
• Nusaviichthys nerivelai
• Pachyamia mexicana
• Paraclupea seilacheri
• Quetzalichthys perrilliatae
• Ranulfoichthys dorsonudum
• Tahnaichthys magnuserrata
• Teoichthys brevipina
• Teoichthys kallistos
• Tepexichthys aranguthyrom
• Tlalocbatos applegatei
• Tlayuamichin itztli
• Unamichthys espinosai
• Ellimmichthys sp.
• cf. Amblysemius
• cf. Bananogmius
• Belonostomus sp.
• cf. Brannerion
• Lepidotes sp.
• cf. Lycoptera
• cf. Megalops
• Neoproscinetes sp.
• Notelops sp.
• cf. Paraelops
• cf. Rhacolepis
• Vinctifer sp.
• cf. Yabrudichthys
• Gonorhynchiform indet.

Arthropods

• Archaeoniscus aranguthyorum
• Atocatle ranulfoi
• Ixtahua benjamini
• Protaegla miniscula
• Tepexicarcinus tlayuaensis
• Sphaeromatidae sp.
• Ostracoda?

Mollusks

• Inoceramus sp.
• Pectinidae indet.
• Osteridae indet.
• Gastropoda indet.
• Neohibolites minimus obtusus
• Neohibolites minimus pinguis
• Neohibolites minimus claviformis
• Neohibolites praeultimus
• Mesohibolites semicanaliculatus
• Martoniceras sp.
• Hysteroceras sp.
• Anisoceras sp.

Echinoderms

• Ophiactis applegatei
• Paleopentacta alencasterae
• Parapsolus tlayuensis
• Astropecten sp.
• Echinaster sp.
• Ophidiaster sp.
• Plutonaster sp.
• Tamaria sp.
• Crinoidea indet.

Other invertebrates

• Porifera
• Anthozoa
• Annelida

Plants

• cf. Araucaria sp.
• cf. Frenolopsis
• Brachyphyllum sp.
• Podozamites sp.
• Zamites sp.
• Phaeophyceae

References

1. Applegate, S. (1988). "A new genus and species of a holostean belonging to the family Ophiopsidae, Teoichthys kallistos, from the Cretaceous, near Tepexi de Rodriguez, Puebla" (PDF). Revista Mexicana de Ciencias Geológicas. 7 (2): 200–205.
2. Pantoja-Alor, Jerjes (1992). "Geología y paleoambiente de la Cantera Tlayúa, Tepexi de Rodríguez Estado de Puebla". Rev. Instituto Geol. UNAM. 9 (2): 156–169.
3. Applegate, Shelton P.; Espinosa-Arrubarrena, Luis; Alvarado-Ortega, Jesús; Benammi, Mouloud (2006), Vega, Francisco J.; Nyborg, Torrey G.; Perrilliat, María Del Carmen; Montellano-Ballesteros, Marisol (eds.), "Revision of Recent Investigations in the Tlayúa Quarry", Studies on Mexican Paleontology, Dordrecht: Springer Netherlands, pp. 275–304, doi:10.1007/1-4020-3985-9_13, ISBN 978-1-4020-3985-0, retrieved 2024-07-16
4. Juárez-Arriaga, Edgar; Barragán, Ricardo; Núñez-Useche, Fernando; Moreno-Bedmar, Josep A. (2023-11-01). "Sedimentary environments in the prelude to the lagerstätten conditions of the Tlayúa Formation (Albian) in central Mexico: A microfacies approach". Journal of South American Earth Sciences. 131: 104650. doi:10.1016/j.jsames.2023.104650. ISSN 0895-9811.
5. Chiocchini, Maurizio; Mancinelli, Anna; Romano, Antonio (1984). "Stratigraphic distribution of benthic Foraminifera in the Aptian, Albian and Cenomanian carbonate sequences of the Aurunci and Ausoni Mountains (Southern Lazio, Italy)". Benthos Research. 1: 167–181.
6. Juárez-Aguilar, E. Aldrin; Sánchez-Beristain, Francisco; Bernal, Juan Pablo; Morton-Bermea, Ofelia; García-Barrera, Pedro (2025-03-01). "Palaeoenvironmental inferences of a Mexican Konservat-Lagerstätte (Tlayúa Quarry; Lower Cretaceous) based on the geochemistry of rare earth elements". Cretaceous Research. 167: 106045. doi:10.1016/j.cretres.2024.106045. ISSN 0195-6671.
7. Espinosa-Arrubarrena, Luis; Applegate, Shelton Pleasants (1996). "A paleoecological model of the vertebrate bearing beds in the Tlayúa Quarries, near Tepexi de Rodriguez, Puebla, Mexico". In Arriata, Gloria; Viohl, Günter (eds.). Mesozoic Fishes – Systematics and Paleoecology. Proceedings of the International Meeting Eichstätt. pp. 539–550. ISBN 9783923871902.
8. Espinosa-Arrubarrena, Luis; Applegate, Shelton Pleasants (1996). "A paleoecological model of the vertebrate bearing beds in the Tlayúa Quarries, near Tepexi de Rodriguez, Puebla, Mexico". In Arriata, Gloria; Viohl, Günter (eds.). Mesozoic Fishes – Systematics and Paleoecology. Proceedings of the International Meeting Eichstätt. pp. 539–550. ISBN 9783923871902.
9. Alvarado-Ortega J, González-Rodríguez KA, Blaco-Piñón A, Espinosa-Arrubarrena L, Ovalles-Damián E (2006). "Mesozoic Osteichthyans of Mexico". In Vega, FJ, TG Nyborg, MC Perrilliat, M. Montellano-Ballesteros, SRS Cevallos-Ferriz. (eds.). Studies on Mexican Paleontology, Topics on Geobiology 24. Dordrecht, Netherlands: Springer Verlag. pp. 169–207. ISBN 1402039859.
10. Vega FJ, Bruce NL, Serrano L, Bishop GA, Perrilliat MD (2005). "A review of the Lower Cretaceous (Tlayúa Formation: Albian) Crustacea from Tepexi de Rodríguez, Puebla, Central Mexico" (PDF). Bulletin of the Mizunami Fossil Museum (32): 25–30. Archived from the original (PDF) on 2011-06-12.
11. Buitrón-Sánchez, Blanca Estela; Durán-Gónzalez, Alicia; Martín-Cao-Romero, Carolina; Solís-Marín, Francisco Alonso; Laguarda-Figueras, Alfredo. "Lower Cretaceous (Albian) Asteroidea (Echinodermata) from Tepexi de Rodriguez, Puebla, Mexico". Revista de Biología Tropical. 63 (2): 7–15.
12. Solé, Jesús; Pi-Puig, Teresa; Bermúdez-Chávez, Cynthia; Garduño-Martínez, Diana; Alvarado-Ortega, Jesús (2022-12-05). "Mineralogy, geochemistry, and K-Ar dating of feldspars and clays from an exceptional Cretaceous fossil locality (Tlayúa, Puebla, Mexico): Insights into the depositional and diagenetic ages and processes". Chemical Geology. 612: 121134. doi:10.1016/j.chemgeo.2022.121134. ISSN 0009-2541.
13. Barrett, Paul M.; Butler, Richard J.; Edwards, Nicholas P.; Milner, Andrew R. (2008). "Pterosaur distribution in time and space: an atlas" (PDF). Zitteliana Reihe B: Abhandlungen der Bayerischen Staatssammlung fur Palaontologie und Geologie. 28: 61–107.
14. Rivera-Sylva, Héctor E.; Carpenter, Kenneth; Frey, Eberhard (2014). Dinosaurs and other reptiles from the Mesozoic of Mexico. Life of the past. Bloomington: Indiana university press. ISBN 978-0-253-01183-1.
15. Reynoso, V.-H. (29 March 1998). "Huehuecuetzpalli mixtecus gen. et sp. nov: a basal squamate (Reptilia) from the Early Cretaceous of Tepexi de Rodríguez, Central México". Philosophical Transactions of the Royal Society B: Biological Sciences. 353 (1367): 477–500. doi:10.1098/rstb.1998.0224. JSTOR 56466. PMC 1692218.
16. Reynoso, Victor-Hugo (1997-04-16). "A "beaded" sphenodontian (Diapsida: Lepidosauria) from the Early Cretaceous of central Mexico". Journal of Vertebrate Paleontology. 17 (1): 52–59. doi:10.1080/02724634.1997.10010953. ISSN 0272-4634.
17. Reynoso, V. H. (2000). "An Unusual Aquatic Sphenodontian (Reptilia: Diapsida) from the Tlayua Formation (Albian), Central Mexico". Journal of Paleontology. 74 (1): 133–148. doi:10.1017/S0022336000031310. JSTOR 1306891.
18. Vega, Francisco J.; Nyborg, Torrey G.; María del Carmen Perrilliat; Marisol Montellano-Ballesteros; Sergio R.S Cevallos-Ferriz; Sara A. Quiroz-Barroso (2006). "Research on Fossil Amphibians and Reptiles". In Landman, Neil H. (ed.). Studies on Mexican Paleontology. Vol. 24. Douglas S. Jones. Dordrecht, Netherlands: Springer. p. 214. ISBN 1-4020-3882-8. Retrieved 31 May 2011.
19. Rodríguez, Katia González; Fielitz, Christopher. "CRETACEOUS OSTEICHTHYAN FISH ASSEMBLAGES FROM MEXICO". Cretaceous Period: Biotic Diversity and Biogeography. New Mexico Museum of Natural History and Science Bulletin. 71.

Further reading

• L. Martin-Medrano and P. Garcia-Barrera. 2006. Fossil Ophiuroids of Mexico. In F. J. Vega, T. G. Nybor, M. D. C. Perrillat, M. Montellano-Ballesteros, S. R. S. Cevallos-Ferriz, S. A. Quiroz-Barroso (eds.), Topics in Geobiology 24:115-131