Opium fish:

According to the rules of classification of left turbot and right plaice, opium fish is a kind of plaice, and the statement that opium fish is an alias of turbot is wrong. The scientific name of the opilio is Greenland flounder.

Partial flounder:

Partial flounder has a long, ovoid, laterally compressed body with a narrow caudal peduncle. Both eyes are located on the right side of the head, and the upper eye is located on the median line of the peripteral margin of the head. The mouth is large, anterior, and symmetrical. Eyed side mostly covered with weak pectinate scales, occasionally interspersed with rounded scales. Eyeless side covered with round scales. Lateral line almost straight. Dorsal fin begins on eyeless side. The pectoral fins are longer on the eyed side. The caudal fin is truncate.