Meeting Abstract
Frogfishes (Family Antennariidae) are highly derived teleost fishes that utilize multiple modes of locomotion, including ambulating on their pectoral fins, in order to move through diverse habitats. Previous literature describes the pectoral fin as having both a shoulder-like and an elbow-like portion, the functions of which are key to frogfishes ability to “walk” with their pectoral fins.These pectoral fins contain small scapula and coracoid bones united by cartilage and three fin radials, the third being distally expanded, articulating with a cartilaginous bar that attaches to a variable number of pectoral fin rays. Frogfishes are also unique in that they have developed 14 muscles associated with the pectoral girdle instead of the 3 muscles typical among neoteleosts, which may aid in their ability to rotate their fins severely around these joints. However, the internal morphology of these unique locomotor adaptations are not well described, or illustrated. In this study, the pectoral fin and pectoral girdle of the shaggy frogfish, Antennarius hispidus, are described using microCT scanning, PTA staining, and clear and stain techniques in order to describe the unique shoulder-like and elbow-like morphologies within the frogfish fin. Future work will include kinematic and electromyographic analyses to explore how this novel pectoral fin structure allows Antennariid fishes to employ their pectoral fins for walking-like locomotion, and explore the evolutionary life history of this unique group of fishes.
