ANOMALIES IN THE CEPHALIC AREA OF LABORATORY-REARED LARVAE AND JUVENILES OF THE COMMON SOLE, SOLEA-SOLEA - ORAL JAW APPARATUS, DERMAL PAPILLAE AND PIGMENTATION

The post-metamorphic common sole, Solea solea, as well as the other Soleidae and Cynoglossidae, are characterized by oral jaw elements without teeth on the ocular side. A relatively large proportion of late sole larvae and early juveniles, routinely reared in the laboratory, showed dentigerous and shape-modified premaxillae and mandibles on the ocular side. Abnormal jaws were associated with dermal papillae and a lack of pigmentation on parts of the ocular side of the head. These features are probably the result of suppressed epigenetic mechanisms normally active during ontogeny. Insights into the morphological evolution of the soleid jaw apparatus are discussed.