Sand Shark Tooth Fossil

EON	ERA	PERIOD	EXTENT (Ma)	DURATION (Ma)
Phanerozoic	Cenozoic	Quaternary	2.588–Present	2.588+
		Neogene	23.03–2.588	20.4
		Paleogene	66.0–23.03	42.9
	Mesozoic	Cretaceous	145.5–66.0	79.5
		Jurassic	201.3–145.0	56.3
		Triassic	252.17–201.3	50.9
	Paleozoic	Permian	298.9–252.17	46.7
		Carboniferous	358.9–298.9	60
		Devonian	419.2–358.9	60.3
		Silurian	443.4–419.2	24.2
		Ordovician	485.4–443.4	42
		Cambrian	541.0–485.4	55.6
Proterozoic	Neoproterozoic	Ediacaran	635.0–541.0	94
		Cryogenian	850–635	215
		Tonian	1,000–850	150
	Mesoproterozoic	Stenian	1,200–1,000	200
		Ectasian	1,400–1,200	200
		Calymmian	1,600–1,400	200
	Paleoproterozoic	Statherian	1,800–1,600	200
		Orosirian	2,050–1,800	250
		Rhyacian	2,300–2,050	250
		Siderian	2,500–2,300	200

SAND SHARK

This tooth is a fossil of an extinct shark species, Striatolamia Macrota, from the Eocene era approximately 54 million years ago. This shark could grow to a length of about 3.5 meters (11.5 ft) and its teeth were notably big for its size.

Sand sharks, also known as sand tiger sharks, grey nurse sharks or ragged tooth sharks, are mackerel sharks of the family Odontaspididae. They are found worldwide in temperate and tropical waters. The three species are in two genera, as well as many extinct species in several genera

The body tends to be brown with dark markings in the upper half. These markings disappear as they mature. Their needle-like teeth are highly adapted for impaling fish, their main prey. Their teeth are long, narrow, and very sharp with smooth edges, with one and on occasion two smaller cusplets on either side. Sand sharks have a large second dorsal fin. The sand shark can grow up to 3.2 m (10 ft) long, and most adults can weigh around 200 kg (440 lb). The average lifespan of both sexes is only about 7 years, though they may live longer in captivity.

The name sand shark comes from their tendency to migrate towards shoreline habitats, and they are often seen swimming around the ocean floor in the surf zone; at times, they come very close to shore. They are often found in warm or temperate waters throughout the world's oceans, except the eastern Pacific. They also frequent the Mediterranean and Adriatic Seas at depths from 20 to 200 m (66 to 656 ft) and sometimes more.

Striatolamia