Cenomani
Cenomani was a Celtic tribe living in Armorica. They are also called Auleric Cenomani who lived in the south east of Mayenne area of present day Normandy.
 

Golg Stater of Cenomani  c. 80-50 BCE.
Obverse: Head facing right.
Reverse: Styalized Horse facing right.
Weight: ~ 7 grams. Size: 22 mm.
Reference:  LT.6852.