Pinheirodon is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of extinct mammal

Mammal

Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...

 from Portugal

Portugal

Portugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...

. It is a member of the also extinct order of Multituberculata

Multituberculata

The Multituberculata were a group of rodent-like mammals that existed for approximately one hundred and twenty million years—the longest fossil history of any mammal lineage—but were eventually outcompeted by rodents, becoming extinct during the early Oligocene. At least 200 species are...

, and shared the world with dinosaur

Dinosaur

Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

s. It is placed in the suborder "Plagiaulacida

Plagiaulacida

Plagiaulacida is a group of extinct multituberculate mammals. Multituberculates were among the most common mammals of the Mesozoic, "the age of the dinosaurs"...

" and family Pinheirodontidae

Pinheirodontidae

Pinheirodontidae is a poorly known family of fossil mammals within the order Multituberculata. Remains are known from the earliest Cretaceous of Europe, , but are so far restricted to teeth. These small plant-eaters lived during the "age of the dinosaurs"...

.

The species on which the genus is based has been designated as Pinheirodon sp. It is known from isolated fossil

Fossil

Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

 teeth.

Initially considered Early Cretaceous, Pinheirodon is from the locality of Porto Dinheiro (Lourinhã

Lourinhã

Lourinhã is a municipality in Portugal with a total area of 147.2 km² and a total population of 24,601 inhabitants. The seat of the municipality is the village of Lourinhã, with a population of 8,800 inhabitants....

, Portugal) which is Late Jurassic (Tithonian).