Αλεκτρυων
During his secret love affair with Aphrodite, Ares stationed a sentry named Alectryon (the cock) with orders to warn him when day was breaking. One morning the sentry went to sleep and thus the Sun took the two lovers by surprise and lost no time in telling Hephaestus, Aphrodite's husband. This was the occasion when Hephaestus had decided to set a trap for his unfaithful wife. Ares was so upset that he changed Alectryon into a rooster, which is why, to this day, these birds call out with the rise of the sun each morning.
{E2 DICTIONARY OF CLASSICAL MYTHOLOGY}
Table of Sources:
- Eustath. on Hom. p. 1598, 61