Abstract
Extra ossicles found in the oral region of Bleekeria vaga are described and illustrated in detail.They are ossified cartilaginous parts of the ligaments or ligamentous structures connecting the following bones and membranes;posterior ends of the maxillary and premaxillary to the anterior end of the dentary;the maxillary to the coronoid process of the dentary;the maxillary to the vomer;articular process of the premaxillary to the maxillary;and the articular process of the premaxillary to the tip of the rostral cartilage.
Similar ossicles are also found in B.gilli and B.renniei.Corresponding cartilaginous structures in B.viridianguilla, Embolichthys mitsukurii, Ammodytes personatus, and A.hexapterus are not ossified.
Among the fishes of the family Ammodytidae, B.vaga and B.gilli seem to have the most protrusile mouth, and the presence of the ossicles seems to have to do with the marked protrusibility of the upper jaw.These ossicles ase also absent in fishes of the Hypoptychidae and Trichonotidae, to which the family Ammodytidae was once considered to be related.
