The Red Spotted Blenny, Istiblennius chrysospilos, is a small combtooth blenny with an elongated body ranging from red-and-white to whitish, overlaid with orange to reddish spotting and irregular narrow bands. Distinctive head coloration further separates it from the many similar-looking blennies offered to hobbyists. The species is widespread through the Indo-Pacific, occurring from East Africa eastward to the Society Islands and north to the Ryukyu Islands, and adults reach roughly 5 inches.

In the wild this blenny occupies shallow, exposed reef flats, reef crests, and surge-swept seaward or fringing reefs where algal growth is prolific. It rarely swims in open water, instead wedging itself into small holes with only the head protruding as it surveys the surrounding rock. That behavior should shape the aquascape at home: adults need a well-established marine system of at least 30 gallons with abundant mature rockwork, small caves, and crevices sized for a fish of this build.

Because it comes from high-energy habitat, brisk water movement suits it well. A continuing crop of natural microalgae on the rock is arguably the single most important element of the setup, as this fish grazes almost constantly. Fit the aquarium with a tight-fitting lid as well, since Red Spotted Blennies are capable jumpers and will find open gaps around overflows and equipment.