Wyvern wyvern is thought to have derived from the figure of the dragon encountered by Trajan's legions in Dacia. It may be the origin of the red dragon of Wales and the golden dragon of the Kingdom of Wessex carried at the Battle of Burford in AD 752. The concept of winged snakes is common in cultures around the Mediterranean, with a notable example being the Egyptian goddess Wadjet. The oldest creatures outright referred to as "winged dragons" are Helios' chariot steeds, which aid Medea. Wyverns are very similar to dragons, and in many languages, cultures and contexts no clear distinction
Mexican heraldry of these rules is a key to the art of heraldry. This system was adapted to Mexican society by incorporating flora and fauna native to Mexico. Another conspicuous difference between Mexican heraldry and European heraldry is the absence of a helm surmounting the shield. Most traditions of Mexican heraldry came from Hispanic or Spanish origin from regions in Spain or Portugal, predominating heraldry of Castilian, Basque or Galician, in second place heraldry of Catalan and Valencian origin. Other common heraldic traditions in Mexico came from French, Italian, German and Polish origins. The most recent heraldic influences, since 1943, are of