three fishes

As a continuation of Bob's fish in the seas post, here are the three 1964 Romanian stamps he doesn't have in this series

Stingrays, like their relatives the sharks, have a skeleton made of cartilage and do not have bones.  Their main predators are these same relatives, the sharks, and also sea lions and seals. Their eyes are on top of their bodies but their mouth, gills and nostrils are on the underside so they can't see their prey and instead use their sense of smell and electroreceptors to find food.
Some stingrays can live from 15 - 25 years in the wild.

The Russian Sturgeon does have bones and is a relic of the dinosaurs. The sturgeon's mouth is on the underside of it's body with four whiskery projections which it uses, along with its sense of smell, to detect prey on the seabed or bottom of the river. It is native to the Black Sea, Caspian Sea and the Azov Sea. They live for a long time - some up to 35 years or more.




The horse mackerel is found in the east Atlantic and the Mediterranean, Caspian and Azov Seas and is thought to be so named because of a legend that smaller fish would hitch a ride on its back to travel long distances. It has a deeply forked tail which makes it fast swimmer. They can grow to 60cm in length.