Two tailed Scylla flanked by a Triton and a tritoness. Silver-gilt phalera. 300 - 100 BCE. Private collection. A phalera is a type of medal, a metal disc, award to Roman soldiers.
A dog’s head emerges from Scylla’s skirt and her two tails curl up on either side of her. The Triton on the left holds what looks like a conch shell in one hand an an oar in the other, and the figure on the right has breasts, meaning she’s a water nymph or tritoness.
Scylla with two tails is also common on ancient Roman coins. Scylla and sirens aren't that common on medals, the only other one I've seen is this two tailed siren medal from the 1400s.
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