''Taveirosaurus'' (meaning " Taveiro lizard") is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of possibly

eutriconodonta Eutriconodonta is an order (biology), order of early mammals. Eutriconodonts existed in Asia (including Insular India, pre-contact India), Africa, Europe, North America, North and South America during the Jurassic and the Cretaceous periods. The ...

mammal A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...

from the Late

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ...

Argilas de Aveiro Formation of

Portugal Portugal, officially the Portuguese Republic, is a country on the Iberian Peninsula in Southwestern Europe. Featuring Cabo da Roca, the westernmost point in continental Europe, Portugal borders Spain to its north and east, with which it share ...

, and also

Laño Laño () is a hamlet and '' concejo'' (a small administrative subdivision) in Condado de Treviño within the Treviño enclave; which is administratively part of the Spanish province of Burgos, but which is completely surrounded by the territo ...

Spain Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...

. The genus is based solely on teeth, and the type species is ''T. costai''.

Discovery and naming

In 1968,

Miguel Telles Antunes Dr. Miguel Telles Antunes (born 11 January 1937) is a Portuguese academic, specializing in paleontology, zooarchaeology, and geology. Antunes is a ranking member of various institutions, including the Lisbon Academy of Sciences, Nova Universi ...

and Giuseppe Manuppella uncovered fossils at the ''Cerâmica do Mondego'' quarry near Taveiro, a village in

, southwest of

Coimbra Coimbra (, also , , or ), officially the City of Coimbra (), is a city and a concelho, municipality in Portugal. The population of the municipality at the 2021 census was 140,796, in an area of . The fourth-largest agglomerated urban area in Po ...

. Among them were a number of low triangular teeth of a herbivorous dinosaur. In 1991 these were named and described by Telles Antunes and

Denise Sigogneau-Russell Denise Sigogneau-Russell (born ''c.'' 1941/42) is a French palaeontologist who specialises in mammals from the Mesozoic, particularly from France and the UK. She is currently based at the Muséum National d'Histoire Naturelle. Background Denise S ...

as the

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

, ''Taveirosaurus costai''. The generic name refers to Taveiro. The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

honours the Portuguese

geologist A geologist is a scientist who studies the structure, composition, and History of Earth, history of Earth. Geologists incorporate techniques from physics, chemistry, biology, mathematics, and geography to perform research in the Field research, ...

João Carrington da Costa.M. Telles Antunes & D. Sigogneau-Russell, (1991), "Nouvelles données sur les dinosaures du Crétacé supérieur du Portugal, ''Comptes Rendus de l'Académie des Sciences à Paris'', Série II 313: 113-119 The

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

, CEGUNL-TV 10, was found in ancient river clay of the Argilas de Aveiro Formation dating from the

Maastrichtian The Maastrichtian ( ) is, in the International Commission on Stratigraphy (ICS) geologic timescale, the latest age (geology), age (uppermost stage (stratigraphy), stage) of the Late Cretaceous epoch (geology), Epoch or Upper Cretaceous series (s ...

. It consists of one tooth. Nine other teeth were also assigned to the genus, CEGUNL-TV 6–9, 11 and 13–16. Later, more teeth found near

were referred to ''Taveirosaurus''.

Classification

Having only the teeth to base themselves on, Telles Antunes and Sigogneau originally thought that ''Taveirosaurus'' belonged to some

pachycephalosauria Pachycephalosauria (; from Greek παχυκεφαλόσαυρος for 'thick headed lizards') is a clade of ornithischian dinosaurs. Along with Ceratopsia, it makes up the clade Marginocephalia. With the exception of two species, most pachyceph ...

n group. In 1991 they assigned it to the Homalocephalidae, in 1992 to the Pachycephalosauridae. However, they soon rejected this possibility, and ''Taveirosaurus'' has not been included in this group in recent reviews. In 1995, it was considered to be a member of the

Nodosauridae Nodosauridae is a family of ankylosaurian dinosaurs known from the Late Jurassic to the Late Cretaceous periods in what is now Asia, Europe, North America, and possibly South America. While traditionally regarded as a monophyletic clade as the ...

. In 1996 Peter Galton suggested it might have belonged to the Fabrosauridae, pointing out a similarity to the teeth of '' Alocodon'' and '' Trimucrodon'', two other "tooth genera".P.M. Galton. (1996). "Notes on Dinosauria from the Upper Cretaceous of Portugal". ''Neues Jahrbuch für Geologie und Paläontologie'' Monatshefte 1996(2): 83-90 In 2004 David B. Norman concluded it was a ''

nomen dubium In binomial nomenclature, a ''nomen dubium'' (Latin for "doubtful name", plural ''nomina dubia'') is a scientific name that is of unknown or doubtful application. Zoology In case of a ''nomen dubium,'' it may be impossible to determine whether a ...

'' and was unable to identify ''Taveirosaurus'' further than

Ornithischia Ornithischia () is an extinct clade of mainly herbivorous dinosaurs characterized by a pelvic structure superficially similar to that of birds. The name ''Ornithischia'', or "bird-hipped", reflects this similarity and is derived from the Greek ...

. A revision of early-diverging ornithischian phylogeny found that instead of ornithischians, the teeth of ''Taveirosaurus'' show the most similarities with members of the early mammal group

Eutriconodonta Eutriconodonta is an order (biology), order of early mammals. Eutriconodonts existed in Asia (including Insular India, pre-contact India), Africa, Europe, North America, North and South America during the Jurassic and the Cretaceous periods. The ...

, lacking characteristics of ornithischian teeth while showing a straight cingulum and linear cusps found within eutriconodontans of similar Cretaceous age.

References

External links

Dinosauria Translation and Pronunciation Guide
{{Taxonbar, from=Q2742079 Maastrichtian life Cretaceous Portugal Fossils of Portugal Fossil taxa described in 1991 Nomina dubia