Wikipedia
In late poetical Greek mythology ichthyocentaurs (or ikhthyokentauroi) were a pair of centaurine sea-gods with the upper body of a male human, the lower front of a horse, and the tail of a fish. Also, they wore lobster-claw horns. They were half-brothers of the wise centaur Chiron and the sons of the Titan Cronus and Nymph Philyra.
These two sea-gods, though little remembered, were set in the sky as the astronomical constellation Pisces.
The twin ichthyocentaurs appear together in several works of art. A first- or second-century mosaic from Zeugma, Commagene, (Z10.1), depicting the birth of Aphrodite, is inscribed with the names of Bythos ("Sea-Depths" or "Depth of Profundity") and Aphros ("Sea-Foam"), who are lifting the goddess' cockle-shell out of the sea. Aphros was perhaps regarded as her foster-father, given their similarity in names. The two sea-gods also appear in a pair of matching sculptures (belonging to the Louvre and Vatican Museums) depicting them carrying Silen companions of the god Dionysus, after his company was driven into the sea by King Lycurgus of Thrace.
The sea-centaurs were probably derived from the divine fish of Syrian mythology (possibly identified with Dagon) that carried Astarte ashore following her watery birth.