Topsail Drummer - Kyphosus cinerascens

Silvery grey with dark horizontal lines on side; rear dorsal fin distinctly elevated (higher than tallest dorsal spines).

Was told that there is another species of Drummer in the picture - Brassy Drummer (Kyphosus vaigiensis), which has more pronounced stripes. To my untrained eyes, still difficult to tell them apart especially when they are mixed in the same group.