Description: fifth gill slit shorter than 4 preceeding ones and located posterior to pectoral fin base; flattened head extending to hammer-like lobes on each side; distinct indentation of the front margin of the head at its midpoint; second dorsal fin longer than tail; gray-brown to olive in color with white underbelly; teeth smooth-edged; pectoral fins tipped with black on the undersurface; tips of first and second dorsal lobes and caudal also may have dusky tips; pelvic fin with nearly straight hind margin.