Alcobaça Formation Explained

Alcobaça Formation
Type:	Geological formation
Age:	Kimmeridgian ~
Period:	Late Jurassic
Prilithology:	Marl
Otherlithology:	Mudstone, coal, siltstone, limestone, sandstone
Namedfor:	Alcobaça, Portugal
Year Ts:	1885
Region:	Estremadura, Leiria, Lisboa
Coordinates:	39.6°N -9°W
Paleocoordinates:	33.7°N 1.6°W
Subunits:	Camadas de Guimarota
Underlies:	Lourinhã Formation
Overlies:	Montejunto Formation
Extent:	Lusitanian Basin

The Alcobaça Formation, previously known as the Guimarota Formation and also known as the Consolação Unit,^[1] is a geological formation in Portugal.^[2] It dates back to the Kimmeridgian stage of the Late Jurassic. It is an important source of information on the diversity of Late Jurassic mammals.^[3] ^[4] Many of the fossils were collected from the now disused and flooded Camadas de Guimarota coal mine.

Vertebrate paleofauna

Dinosaur eggs are geographically located in Lisbon District, Portugal. Dinosaur tracks are geographically located in Leiria District, Portugal.

Chondrichthyes

Chondrichthyes of the Alcobaça Formation
Genus	Species	Location	Material
Hybodus^[5]	Indeterminate	Guimarota	Isolated Teeth
Asteracanthus	A. biformatus	Guimarota	isolated teeth, fin-spine and a head-spine
Polyacrodus	Indeterminate	Guimarota	Isolated teeth and a fin-spine
Orectolobiformes	Indeterminate	Guimarota	One isolated tooth
Batomorphii	Indeterminate	Guimarota	Isolated teeth

Osteichthyes

Osteichthyes of the Alcobaça Formation
Genus	Species	Location	Material	Notes
Macromesodon	Indeterminate	Guimarota	Isolated teeth
Proscinetes	Indeterminate	Guimarota	Isolated teeth and prearticulars
"Lepidotes"	Indeterminate	Guimarota	isolated lateral teeth, lower jaws, ganoid scales and isolated skull bones	Two species of different size can be distinguished from the fossil material
Ionoscopidae	Indeterminate	Guimarota	Isolated teeth
Macrosemiidae	Indeterminate	Guimarota	Isolated grasping tooth
Caturus?	Indeterminate	Guimarota	Isolated Teeth and a partial skull
Pachycormidae	Indeterminate	Guimarota

Amphibians

Albanerpetontids are one of the most numerous faunal components of the Guimarota mine with around 9000 isolated remains, including parts of the skull and limbs. Remains of indeterminate salamanders and frogs are also present but far rarer.

Amphibians of the Alcobaça Formation
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
cf. Celtedens	Indeterminate	Porto Pinheiro			Albanerpetontid
cf. Marmorerpeton	Indeterminate	Guimarota			Indeterminate salamander
Discoglossidae	Indeterminate	Guimarota			Indeterminate frog

Ornithischians

Indeterminate euornithopod remains located in Lisbon District. Indeterminate stegosaurid remains present in Lisbon District.

Ornithischians of the Alcobaça Formation
Genus	Species	District	Stratigraphic position	Abundance	Notes	Images
Dacentrurus	D. armatus	Lisboa
Ornithopoda	Indeterminate	Lisboa
Stegosaurus^[6]	S. cf. ungulatus				"...one tooth, five cervical vertebrae (including the axis), five dorsal vertebrae, cervical and dorsal ribs, three caudal vertebrae, chevrons, preacetabular process of the left ilium, right tibia, fibula, astragalus and [calcaneus], a cervical plate, and several fragments of plates."
Trimucrodon	T. cuneatus	Lisboa			Later determined to be indeterminate ornithischian remains.

Saurischians

Indeterminate sauropod remains located in Leiria and Lisboa.^[7]

Saurischians of the Alcobaça Formation
Genus	Species	District	Stratigraphic position	Abundance	Notes	Images
Allosaurus^[8]	Indeterminate	Leiria
Aviatyrannis	A. jurassica	Guimarota
Lusotitan^[9]	L. atalaiensis	Lisboa
Ceratosaurus	Indeterminate	Lisboa
Dinheirosaurus	D. lourinhanensis	Lisboa		"[Two] cervicals, [nine] dorsals, ribs, limb elements."^[10]
Lourinhasaurus	L. alenquerensis	Lisboa
Megalosaurus	M. insignis	Lisboa			Later determined to be indeterminate theropod remains.

Pterosaurs

Pterosaurs of the **Alcobaça Formation**
Genus	Species	Location	Stratigraphic Position	Material	Notes	Images
aff. Rhamphorhynchus	Indeterminate	Guimarota		Isolated Fragments
Pterodactyloidea	Indeterminate	Guimarota		Teeth

Turtles

Turtles of the Alcobaça Formation
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Peltochelys	P. duchastelli	Guimarota
Platychelys	Indeterminate	Guimarota
	Indeterminate	Guimarota

Lepidosauromorphs

Lepidosauromorphs of the Alcobaça Formation
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Becklesius	B. hoffstetteri	Guimarota			Paramacellodid lizard
Dorsetisaurus	D. purbeckensis	Guimarota			Anguimorph lizard
Marmoretta	Indeterminate	Guimarota			Basal Lepidosauromorph
Portugalophis	P. lignites	Guimarota			Stem-snake
Saurillodon	S. proraformis	Guimarota			A lizard
Saurillus	S. henkeli, cf. obtusus	Guimarota			A lizard
cf. Opisthias^[11]	Indeterminate	Andrés, Pombal			A rhynchocephalian

Crocodyliformes

Crocodyliformes of the Alcobaça Formation
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Goniopholis	G. baryglyphaeus	Guimarota			A goniopholidid
Knoetschkesuchus	K. guimarotae	Guimarota			An atoposaurid
Lisboasaurus	L. mitracostatus	Guimarota
Machimosaurus	M. hugii	Guimarota			A marine machimosaurid

Mammals

Mammals of the Alcobaça Formation
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Bathmochoffatia	B. hapax	Guimarota			A paulchoffatiid multituberculate
Bernardodon	B. sp, B. atlanticus	Porto Pinheiro			A pinheirodontid multituberculate
Drescheratherium	D. acutum	Guimarota			A paurodontid dryolestidan
Dryolestes	D. leirensis	Guimarota			A dryolestid dryolestidan
Ecprepaulax	E. anomala	Porto Pinheiro			A pinheirodontid multituberculate
Guimarotodon	G. leiriensis	Guimarota			A paulchoffatiid multituberculate
Guimarotodus	G. inflatus	Guimarota			A dryolestid dryolestidan
Haldanodon	H. exspectatus	Guimarota			A docodont
Henkelodon	H. naias, H. sp	Guimarota			A paulchoffatiid multituberculate
Henkelotherium	H. guimarotae	Guimarota			A dryolestidan
Iberodon	I. quadrituberculatus	Porto Pinheiro			A pinheirodontid multituberculate
Kielanodon	K. hopsoni	Guimarota			A paulchoffatiid multituberculate
Krebsotherium	K. lusitanicum	Guimarota			A dryolestid dryolestidan
Kuehneodon	K. guimarotensis, K. dietrichi, K. simpsoni, K. uniradiculatus, K. sp	Guimarota			A paulchoffatiid multituberculate
Laolestes	L. andresi	Porto Pinheiro			A dryolestid dryolestidan
Meketibolodon	M. robustus	Guimarota			A paulchoffatiid multituberculate
Meketichoffatia	M. krausei, M. sp	Guimarota			A paulchoffatiid multituberculate
Nanolestes	N. krusati	Porto Pinheiro			A cladotherian
Nanolestes	N. drescherae	Guimarota			A cladotherian
Paulchoffatia	P. delgadoi	Guimarota			A paulchoffatiid multituberculate
Pinheirodon	P. sp, P. vastus, P. pygmaeus	Porto Pinheiro			A pinheirodontid multituberculate
Plesiochoffatia	P. thoas, P. peperethos	Guimarota			A paulchoffatiid multituberculate
Portopinheirodon	P. asymmetricus	Porto Pinheiro			A dryolestid dryolestidan
Priacodon	Indeterminate	Porto Pinheiro			A triconodontid
Proalbionbaatar	P. plagiocyrtus	Guimarota			A multituberculate of uncertain placement
Pseudobolodon	P. dryas, P krebsi, P. oreas	Guimarota			A paulchoffatiid multituberculate
Renatodon	R. amalthea	Guimarota			A paulchoffatiid multituberculate
? Tinodon	Indeterminate	Porto Pinheiro			A tinodontid symmetrodont
Xenachoffatia	X. oinopion	Guimarota			A paulchoffatiid multituberculate
Paulchoffatiidae	Indeterminate	Guimarota			4 distinct genera with 7 species
Pinheirodontidae	Indeterminate	Porto Pinheiro

Invertebrate Paleofauna

Ostracods

Ostracods of the **Alcobaça Formation**
Genus	Species	Notes
Cetacella	C. armata	Cetacella is a typical component of Late Jurassic brackish water environments in Europe. Member of the Cypridacea
	C. inermis
	C. striata
Theriosynoecum	T. wyomingense	Member of the Cytheracea
Bisulcocypris	B. pahasapensis	Member of the Cytheracea
Timiriasevia	T. guimarotensis	Member of the Cytheracea
Poisia	P. bicostata	Member of the Cytheracea
Poisia	P. clivosa	Member of the Cytheracea
Dicrorygima	D. reticulata	Member of the Cytheracea
Darwinula	D. leguminella	Member of the Darwinulacea

Mollusca

Bivalves

Bivalves of the **Alcobaça Formation**
Genus	Species	Location	Stratigraphic Position	Material	Notes	Images
Isognomon	I. rugosus	Guimarota		Dozens of well preserved shells sometimes making up entire stratigraphic layers	This genus is regarded as an indicator for brachyhaline water conditions and it was likely buried in its natural habitat
"Unio"	"U." cf. alcobacensis	Guimarota		Dozens of well preserved shells with articulated valves	freshwater clam

Gastropods

Gastropods of the **Alcobaça Formation**
Genus	Species	Location	Material	Notes
Teinostoma	Indeterminate	Guimarota	Shells	Boring traces of clionidid sponges on the shells of this taxon indicate a marine lifestyle
Cryptaulax	Indeterminate	Guimarota	Shells
Melampoides	M. jurassicus	Guimarota	Shells	Boring traces of clionidid sponges on the shells of this taxon indicate a marine lifestyle, modern relatives like Melampus also venture onto land, which can also be expected from M. jurassicus

References

Bibliography

Notes and References

Mateus. O.. Dinis. J.. Cunha. P. P.. 2017-09-28. The Lourinhã Formation: the Upper Jurassic to lower most Cretaceous of the Lusitanian Basin, Portugal – landscapes where dinosaurs walked. Ciências da Terra / Earth Sciences Journal. 19. 1. 75–97. 10.21695/cterra/esj.v19i1.355. 2183-4431. free. 10316/79879. free.
Fürsich. Franz T.. Schneider. Simon. Werner. Winfried. Lopez-Mir. Berta. Pierce. Colm S.. 2021-09-13. Life at the continental–marine interface: palaeoenvironments and biota of the Alcobaça Formation (Late Jurassic, Central Portugal), with a formal definition of the unit appended. Palaeobiodiversity and Palaeoenvironments. 102 . 2 . 265–329 . 10.1007/s12549-021-00496-x. 1867-1608. free.
Web site: Guimarota. Paleobiology Database. 31 August 2018.
Web site: Porto Pinheiro, Lourinha. Paleobiology Database. 31 August 2018.
Palmer . Douglas . September 2001 . M ARTIN, T. & K REBS, B. (eds) 2000. Guimarota. A Jurassic Ecosystem . 155 pp. München: Verlag Dr. Friedrich Pfeil. Price DM 120.00 (hard covers). ISBN 3 931516 80 6. . Geological Magazine . 138 . 5 . 619–630 . 10.1017/S0016756801316084 . 0016-7568.
Escaso . Fernando . Ortega . Francisco . Dantas . Pedro . Malafaia . Elisabete . Pimentel . Nuno L. . Pereda-Suberbiola . Xabier . Sanz . José Luis . Kullberg . José Carlos . Kullberg . María Carla . 2006-12-23 . New evidence of shared dinosaur across Upper Jurassic Proto-North Atlantic: Stegosaurus from Portugal . Naturwissenschaften . 94 . 5 . 367–374 . 2007NW.....94..367E . 10.1007/s00114-006-0209-8 . 17187254 . 10930309.
"16.1 Distrito do Leiria, Portugal; 3. Camadas de Alcobaça," and "16.4 Distrito do Lisboa, Portugal; 1. Camadas de Alcobaça," in Weishampel, et al. (2004). Pages 548-549.
"16.1 Distrito do Leiria, Portugal; 3. Camadas de Alcobaça," in Weishampel, et al. (2004). Page 548.
"16.4 Distrito do Lisboa, Portugal; 1. Camadas de Alcobaça," in Weishampel, et al. (2004). Page 548.
"Table 13.1," in Weishampel, et al. (2004). Page 265.
Malafaia . E. . Ortega . F. . Escaso . F. . Dantas . P. . Pimentel . N. . Gasulla . J. M. . Ribeiro . B. . Barriga . F. . Sanz . J. L. . 2010 . Vertebrate fauna at the Allosaurus fossil-site of Andrés (Upper Jurassic), Pombal, Portugal . Journal of Iberian Geology . 36 . 2 . 193–204 . 10.5209/rev_JIGE.2010.v36.n2.7 . 1698-6180. free .