The Ranchu is a hooded variety of fancy goldfish developed in Japan. It is referred to as the "king of goldfish" by the Japanese.
The Lionhead Goldfish is often confused and wrongly identified as a Ranchu as both of them bear very close resemblance to each other.
Ranchus have a more downturned tail and tail fin. Although similar to lionheads, ranchus have more-arched backs and have much shorter tails that are tucked-in at a 45 degree angle. This goldfish does not have a dorsal fin.