Sinemurian

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The Sinemurian is a stage of the Early Jurassic Epoch. It spans the time between 196.5 ± 2 Ma and 189.6 ± 1.5 Ma (million years ago).

The stage takes its name from the town of Semur-en-Brionnais, near Sancerre in the upper Loire Valley. The calcareous soil formed from the Jurassic limestone of the region is in part responsible for the character of the classic Sancerre wines.

In Europe this period, together with the Hettangian, is also known as the Lower (or Blue) Lias Stage.

Contents 1 Vertebrate Fauna 1.1 Ichthyosaurs 1.2 Mammaliaformes 1.3 Ornithischians 1.4 Plesiosaurs 1.5 Theropoda 2 References

[edit] Vertebrate Fauna

[edit] Ichthyosaurs

Ichthyosauria of the Sinemurian
Taxa	Presence	Location	Description	Images
Ichthyosaurus	From Hettangian to Sinemurian	Belgium, England, Germany	Among the best known ichthyosaur genera, was smaller than most of its relatives, measuring 2 m (6 ft 8 inches) in length.	Ichthyosaurus

[edit] Mammaliaformes

Mammaliaformes of the Sinemurian
Taxa	Presence	Location	Description	Images
Hadrocodium		Yunnan, China	The earliest known example of several features distinctive to mammals, including mammal-like mandible and middle-ear structures and a relatively large brain cavity

[edit] Ornithischians

Ornithischians of the Sinemurian
Taxa	Presence	Location	Description	Images
Abrictosaurus	From Hettangian to Sinemurian	Upper Elliot Formation, Lesotho and Cape Province, South Africa	Considered the most basal member of the family Heterodontosauridae	Abrictosaurus Scelidosaurus
Fabrosaurus	From Hettangian to Sinemurian	Lesotho	As the only fossil known of it is a partial jawbone with three teeth, Fabrosaurus is a nomen dubium and may in fact be the same as Lesothosaurus.
Geranosaurus		Clarence Formation, Cape Province, South Africa	With few remains, it is considered a nomen dubium. It is classified as an ornithischian based on the jaw.
Lanasaurus	From Hettangian to Sinemurian	Upper Elliot Formation, Orange Free State, South Africa	A heterodontosaurid ornithischian
Lusitanosaurus	Dated disputed	Unknown location in Portugal	Only known from a partial snout with teeth
Lycorhinus	From Hettangian to Sinemurian	Upper Elliot Formation, Cape Province, South Africa	A small herbivore dinosaur despite long canines it sported in its jaws; due to this unique characteristic it is very clearly allied to Heterodontosaurus
Merosaurus		England	Disputed, considered by some to be a tetanuran theropod
Scelidosaurus	From Hettangian to Sinemurian	Charmouth, West Dorset, England; Kayenta Formation, Arizona, USA	A genus of quadrupedal, lightly plated, herbivorous dinosaur about 4 meters long (13 ft)
Stormbergia	From Hettangian to Sinemurian	Stormberg Series Formations, South Africa, Lesotho	A primitive ornithischian, about 2 meters long. The proportions of the posterior limbs show differences with those of Lesothosaurus, and reveal a lower ability to run

[edit] Plesiosaurs

Plesiosauria of the Sinemurian
Taxa	Presence	Location	Description	Images
Eretmosaurus		Granby, Leicestershire, England	May have been a rhomaleosaurid, pliosaurid or elasmosaurid	Plesiosaurus
Plesiosaurus dolichodeirus	Sinemurian and Toarcian	Lyme Regis, Dorset, England	A large (about 3 to 5 meters long), marine sauropterygian reptile, it was distinguished by its small head, long and slender neck, broad turtle like body, a short tail, and two pairs of large, elongated paddles

[edit] Theropoda

Theropods of the Sinemurian
Taxa	Presence	Location	Description	Images
Dilophosaurus	Sinemurian to Pliensbachian	Arizona, USA; Yunnan, China	Measured around six meters (20 ft) long and may have weighed half a ton. The most distinctive characteristic of Dilophosaurus is the pair of rounded crests on its skull, possibly used for display.	Dilophosaurus

[edit] References

• GeoWhen Database - Sinemurian

Jurassic period
Lower/Early Jurassic	Middle Jurassic	Upper/Late Jurassic
Hettangian | Sinemurian Pliensbachian | Toarcian	Aalenian | Bajocian Bathonian | Callovian	Oxfordian | Kimmeridgian Tithonian