Alcobaça Formation
Alcobaça Formation
Stratigraphic range : Oxfordian -Kimmeridgian ~156.9–152.5 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Lithology
Location
Coordinates 39°36′N 9°00′W/39.6°N 9.0°W/ 39.6; -9.0
Approximate paleocoordinates 33°42′N 1°36′E/33.7°N 1.6°E/ 33.7; 1.6
Type section
Year defined 1885
The Alcobaça Formation , previously known as the Guimarota Formation and also known as the Consolação Unit, is a geological formation in Portugal . 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. 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 FormationGenus Species Location Stratigraphic Position Material Notes Images Hybodus 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 Batomorphi Indeterminate Guimarota Isolated teeth
Osteichthyes Osteichthyes of the Alcobaça FormationGenus Species Location Stratigraphic Position Material Notes Images Guimarotaichthys G. problematicus Guimarota A non-teleost bony fish 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 FormationGenus Species Location Stratigraphic position Material Notes Images cf. Celtedens Indeterminate Porto Pinheiro Albanerpetontid cf. Marmorerpeton Indeterminate Guimarota Indeterminate salamander Nabia N. civiscientrix Guimarota Albanerpetontid Discoglossidae Indeterminate Guimarota Indeterminate frog
Choristoderes Choristoderes of the Alcobaça FormationGenus Species Location Stratigraphic position Material Notes Images Cteniogenys Indeterminate Guimarota
Ornithischians Indeterminate euornithopod remains located in Lisbon District. Indeterminate stegosaurid remains present in Lisbon District.
Ornithischians of the Alcobaça FormationGenus Species District Stratigraphic position Abundance Notes Images Dacentrurus D. armatus Lisboa Stegosaurus 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.
Saurischians of the Alcobaça FormationGenus Species District Stratigraphic position Abundance Notes Images Allosaurus Indeterminate Guimarota MG 27804, an isolated maxilla belonging to a hatchling individual The ontogenetically youngest and stratigraphically oldest Portuguese Allosaurus fossil Aviatyrannis A. jurassica Guimarota Lusotitan L. atalaiensis Lisboa Ceratosaurus Indeterminate Lisboa Dinheirosaurus D. lourinhanensis Lisboa "[Two] cervicals, [nine] dorsals, ribs, limb elements." 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 FormationGenus Species Location Stratigraphic position Material Notes Images Peltochelys P. duchastelli Guimarota Platychelys Indeterminate Guimarota Pleurosternidae Indeterminate Guimarota
Lepidosauromorphs Lepidosauromorphs of the Alcobaça FormationGenus Species Location Stratigraphic position Material Notes Images Becklesius B. hoffstetteri Guimarota Paramacellodid lizardDorsetisaurus D. purbeckensis Guimarota Anguimorph lizardMarmoretta M. drescherae 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 Indeterminate Andrés, Pombal A rhynchocephalian
Crocodyliformes Crocodyliformes of the Alcobaça FormationGenus 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 FormationGenus 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 N. drescherae Guimarota 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
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
Invertebrate Paleofauna Ostracods Ostracods of the Alcobaça Formation Genus Species Location Stratigraphic Position Material Notes Images 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 P. clivosa 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 Stratigraphic Position Material Notes Images 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
See also Bibliography Weishampel, David B.; Dodson, Peter; Osmólska, Halszka (2004), , Berkeley: University of California Press, pp. 1–880, ISBN 0-520-24209-2 {{citation}}: CS1 maint: publisher location (link)