Ichthyocentaurs

Ichthyocentaurs are figures from classical mythology linked to the sea, better described as fish-centaurs, the upper part of their body was human in form and the lower part in the shape of a fish tail, similar to mermaids. This connotation differentiates them from the most famous centaurs, other mythological figures that were half man and half horse.
The ichthyocentaurs are depicted in many mosaics, together with tritons and nereids, as members of the marine thiasos accompanying Poseidon, a recurring theme in classical iconography.