coursed ventrally, passing through the upper fin ray bases;
the main ventral branch entered the ventralmost fin ray
base and coursed dorsally, passing through the lower fin ray
bases; the 2 main branches, forming a continuous transverse
nerve along the fin base, supply branches posteriorly into
the rays (1 for each), each branch being sandwiched by the
ray halves. In forming a transverse nerve supplying a number of branches to the rays, the caudal and pectoral (Fig. 5B)
fins are identical. Thus, the innervation pattern of the claval
fin rays is clearly identical with those in the dorsal and anal
fin rays, but differs from that of the caudal fin rays, thereby
providing a strong support for the hypothesis that the clavus
is formed by elements of the dorsal and anal fin (Johnson
and Britz, 2005).