Eotyrannus lengi Click to enlarge image
Model of eotyrannus lengi in Bałtów Jurassic Park, Bałtów, Poland Image: Krugerr
© CC BY SA

Fast Facts

  • Classification
    Species
    lengi
    Genus
    Eotyrannus
    Super Family
    Tyrannosauroidea
    Suborder
    Theropoda
    Order
    Saurischia
    Superorder
    Dinosauria
    Class
    Reptilia
    Subphylum
    Vertebrata
    Phylum
    Chordata
    Kingdom
    Animalia
  • Size Range
    4 to 5 metres long
  • Life history mode
    territorial
  • Feeding Habits
    carnivorous
  • View Fossil Record
    Fossil Record
    Cretaceous Period
    (141 million years ago - 65 million years ago)

Introduction

Pronounced Ee-o-tie-ran-us leng-ee

Eotyrannus means ‘dawn tyrant’ in Greek) and lengi honours its discoverer Gavin Leng.

The relatively small tyrannosaur Eotyrannus lived about 60 million years before its more famous relative Tyrannosaurus rex.

Identification

Aside from some fragmentary fossils from Portugal, Eotyrannus was the first tyrannosaur described from Europe and one of the first early tyrannosaurs known. The only known specimen is a subadult (teenager), represented by a partial skull, vertebrae, shoulder, forelimb, partial pelvis and hindlimb.

As a tyrannosauroid Eotyrannus shares the following characteristics with other tyrannosaurs: serrated premaxillary teeth with a D-shaped cross section, and proportionally elongate tibiae (shine bones) and metatarsals (foot bones). As a primitive tyrannosaur, it has long neck vertebrae and long, well-developed forelimbs with three fingers on each long, slender hand.

Habitat

The Isle of Wight, where Eotyrannus was found, has produced rich plant and animal life from the earliest Cretaceous (including the first dinosaur described as such, the plant-eating Iguanodon). Eotyrannus was found near the remains of a plant-eating ornithopod, in amongst plant debris, and perhaps died in a flood.

Distribution

Eotyrannus lived in what is now England, Europe, during the Early Cretaceous, about 131-126 million years ago.

Feeding and diet

Eotyrannus had the teeth and build of a predator and was probably fast and agile, with unusually long legs. Its prey may have included such plant-eating dinosaurs as Hypsilophodon and Iguanodon, along with other small- to medium-sized mammals and reptiles.

Fossils description

The first fossils were found in 1995 and named and described in 2001.

The only known specimen is a subadult ('teenager'), represented by a partial skull, vertebrae, shoulder, forelimb, partial pelvis and hindlimb.

Some of the fossil bones were articulated (which means they were still attached to each other), whilst others were jumbled in new positions. This suggests the animal may have been partially scavenged after it died and before it was buried. The rock containing the fossils also includes bones from two other dinosaurs. Did they all die together? We may never know.

Evolutionary relationships

Eotyrannus has yet to be placed into one of the two known tyrannosaur families. Its closest relatives are Juratyrant and Stokesosaurus.

References

Hutt, S., Naish, D., Martill, D.M., Barker, M.J., and Newbery, P. (2001). "A preliminary account of a new tyrannosauroid theropod from the Wessex Formation (Cretaceous) of southern England." Cretaceous Research, 22: 227–242.