Living lamniform sharks are the last survivors of a much larger lamniform lineage that has mostly gone extinct. The 15 living species are insignificant to the hundredsdocumented from fossils; the genus Carcharodon alone would be known from 10 ancient species, as opposed to the solitary extant Carcharodon carcharias.
However, the large bulk of these fossils are solitary teeth that first appeared in the fossil record 120 million years ago during the early Cretaceous era (mya). Let's begin with the building materials.
Fossil lamniform teeth have been found in a variety of marine environments across all continents, and they match those of modern mackerel sharks in that they are typically thin, with highly sharp cusps and arching roots. Many current lamniform species have fossil cousins that are only known from their teeth and date back to the Paleocene epoch (some 62 mya).
Some of these ancient species are even placed in current genera (e.g., Carcharodon,Odontaspis), confirming that lamniform sharks, like other existing shark groups, have a remarkably lengthy evolutionary history.
Fossil extinct mackerel sharks known from more complete remains are exceedingly rare and include conserved partial bones of goblin sharks (Mitsukurinidae) from Lebanon (about 90 million years old), as well as vertebrae from diverse taxa, including the megalodon shark from Europe.
The late Cretaceous goblin shark has a highly extended snout like the contemporary goblin species (Mitsukurina owstoni), but it has a considerably longer anal fin and more angular dorsal fins. Furthermore, several characteristics of its teeth and denticles differ.
The most well-known fossil lamniform is the megalodon shark (Carcharodon megalodon). It is recognized by its massive, triangular teeth (as tall as 7.9 in [20 cm]) that resemble the fangs of a living white shark. The megalodon shark, on the other hand, was three times the size of the extant white and one of the largest marine predators of all time (estimated to be up to 49 ft [15m] in length) (and the macro predatory shark).
Living lamniform sharks are some of the most researched and well-known sharks. Four live species were documented in the 18th century, five in the 19th century, and six in the 20.