Among celtic iconography there was a motif of ram-horned snake.
The animal is often pictured on gallo-roman sculptures/relief/altars, where it accompanies particular god, or goddess, more rarely a couple.
It is interpreted as a symbol of vitality, fertility, reborn/resurrection. Often around god/dess wrist reaching for fruit or patera.
She is the personification of this mythical creature, of which I have no info about any written sources left.
Her look is part of the dream she appeared.