''Megalolamna'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of lamniform

shark Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimo ...

that belongs to the family

Otodontidae Otodontidae is an extinct family of sharks belonging to the order Lamniformes. Its members have been described as megatoothed sharks. They lived from the Early Cretaceous to the Pliocene, and included genera such as ''Carcharocles'' and ''Otodus ...

. Its name comes from the similarity of its teeth to those of the extant shark genus ''

Lamna ''Lamna'' is a genus of mackerel sharks in the family Lamnidae, containing two extant species: the porbeagle (''L. nasus'') of the North Atlantic and Southern Hemisphere, and the salmon shark (''L. ditropis'') of the North Pacific. Endothermy T ...

.'' It is known from the early Miocene Chilcatay Formation of

Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = Seal (emblem), National seal , national_motto = "Fi ...

, Oi and O'oshimojo Formations of

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

, and the

Jewett Sand Formation The Jewett Sand Formation is a geologic formation in California, USA. It preserves fossils dating back to the Miocene Epoch of the Neogene period. Vertebrates Cartilaginous fishes Sharks 200px, Fossil teeth of ''C. hastalis'' *''†Alopias ...

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

and Pungo River Formation,

North Carolina North Carolina () is a state in the Southeastern region of the United States. The state is the 28th largest and 9th-most populous of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, Georgia and So ...

in the United States, implying a cosmopolitan distribution. The largest specimen is estimated to have measured about long.

Taxonomy

It is considered to be the sister genus of ''

Otodus ''Otodus'' is an extinct genus of mackerel shark which lived from the Paleocene to the Pliocene epoch. The name ''Otodus'' comes from Ancient Greek (, meaning "ear") and (, meaning "tooth") – thus, "ear-shaped tooth". Anatomy This shark is k ...

''. The study of ''Megalolamna'''s taxonomic relationships also demonstrates the possibility that ''Otodus'' needs to include the species sometimes assigned to ''

Carcharocles ''Otodus'' is an extinct genus of mackerel shark which lived from the Paleocene to the Pliocene epoch. The name ''Otodus'' comes from Ancient Greek (, meaning "ear") and (, meaning "tooth") – thus, "ear-shaped tooth". Anatomy This shark is k ...

'' (i.e., the megatoothed lineage, including

megalodon Megalodon (''Otodus megalodon''), meaning "big tooth", is an extinct species of mackerel shark that lived approximately 23 to 3.6 million years ago (Mya), from the Early Miocene to the Pliocene epochs. It was formerly thought to be a member ...

) in order to be

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

References

{{Taxonbar, from=Q27092801 Otodontidae Prehistoric marine animals Miocene fish of Asia Fossils of Japan Miocene fish of North America Neogene California Fossils of North Carolina Prehistoric fish of South America Miocene animals of South America Neogene Peru Fossils of Peru Fossil taxa described in 2016