P. dentatus is one member of a large family of distinctive benthic flatfishes that inhabit continental shore waters in the tropical and temperate zones of the Atlantic, Pacific and Indian oceans. Flatfishes such as the flounders are unlike most other fishes in that they begin life as bilateral animals, having equal right and left side, and swim as do other fishes. However, toward the end of the larval period, flatfishes settle to the benthos and take up a cryptic, somewhat sedentary lifestyle, lying on one side of the body, and swimming laterally to the substratum. Metamorphosis to the juvenile stage involves complex modification of the skeletal structure of the head, and rearrangement of the nervous system and muscle tissues. Additionally, the eye on the side that faces the substratum (termed the blind-side eye) begins to migrate to the upper side of the body. P. dentatus is a left-eye flounder, thus it lies on its right side, and at metamorphosis, the right eye migrates to the left side of the head. Lefteye flounders sometimes exhibit sexual dimorphism, with females having eyes that are closer together than in males, and males having somewhat longer pectoral fins (Rogers and Van Den Avyle 1983).