How It Works-Book Of Dinosaurs

Plesiosaurus was an unusual long-necked

marine reptile that lived in the Early Jurassic

period (circa 199-175 million years ago).

This member of the sauropter ygian superorder

measured in at approximately 4.5 metres (15 feet) in

length, sported a muscular and stock y body, a long

and narrow neck, plus a short, stubby tail. Four large

flipper-like limbs that attached in pairs to the torso

allowed the creature to propel itself through the

water at great speed, while a small head packed with

rows of sharp, curved teeth ensured that once it got

hold of its dinner there was no getting away.

Despite the reptile’s under water dominance, the

Plesiosaurus could not in fact breathe under water

like fish so had to surface to draw in air. Due to its

size, however, it could spend a considerable length

of time submerged, allowing it to repeatedly dart

through shoals of fish and squid while hunting.

Plesiosaurus inhabited the shallow seas of what is

now Europe, dominating the waters due to its size,

agilit y and ferocit y. Early in their histor y, this

domination reached new heights when the order

split-evolved into two main lineages: Pliosaurs and

Plesiosaurids. The former developed a shorter neck

and elongated head, while the latter developed a

snake-like neck of epic proportions. This divergence

allowed the species in each lineage to prey on an

increasingly varied range of creatures, with some

giants, such as Pliosaurus funkei (formerly ‘Predator

X’), even capable of attacking other Plesiosaurs.

Plesiosaurus became extinct at the opening of the

Middle Jurassic period (175 MYA), being superseded

by its larger, more dominant relatives, like the

Elasmosaurus. The Plesiosauria order, however,

sur vived much longer, thriving worldwide until

the Cretaceous-Tertiary (K-T) extinction event.

Plesiosaurus

We turn the spotlight on a ferocious marine reptile that

dominated Earth’s oceans throughout the Early Jurassic

Plesiosaurus

Length: 4.5m (15ft)

Neck vertebrae: 40

Weight: 90kg (200lb)

Diet: Carnivore; eg fish, squid

Discovered: Dorset, UK

The statistics...

Streamlined

A muscular torso allows

for great propulsion

DINOSAURS

Plesiosaurus