Essential Guide to Identifying Reef Fish in Florida and the Caribbean

Underwater Life in the Caribbean

Just beneath the twinkling, satin surface of the Caribbean, you find schools of fish of a thousand different shapes and colors. The surprising variety of finned friends is one of the reasons people get hooked on scuba diving. To identify some of the most common and interesting reef fish in the Caribbean, Florida, and the Western Atlantic, look for their distinctive characteristics.

French Grunts and Blue-Striped Grunts

French grunts (Haemulon flavolineatum) and blue-striped grunts (Haemulon sciurus) are quite common and can be seen on nearly every shallow reef dive in the Caribbean. Grunts are so-named because they make a grunting sound by grinding their teeth together and amplifying the noise with their air bladders.

The key to identifying a French grunt is to look at the stripes along the side of its body. The first few rows of stripes run lengthwise down the fish’s body, but the lower stripes are diagonal.

The blue-striped grunt has obvious blue stripes that may appear to be outlined in a darker blue upon close examination. The easiest way to identify a blue-striped grunt is by its dark, brownish tail fin and dorsal (top) fin.

Smooth Trunkfish

The smooth trunkfish (Lactophrys triqueter) can be one of the most entertaining fish to watch on a dive. Not only is it cute—who doesn’t love its puckered-lip look and its fancy white polka dots—but it always seems to be hunting for food. These smallish fish are frequently seen over sandy areas near the reef, where they blow little jets of water at the sand in an attempt to uncover food. Although they are slow-moving, smooth trunkfish do not seem to be bothered by divers’ presence. They continue their sand blowing as long as divers approach calmly.

Trumpetfish

Trumpetfish (Aulostomus maculatus) are easy to identify by their long, thin, tubular bodies with trumpet-shaped mouths or snouts. Trumpetfish can be brown, reddish, bluish, or bright yellow. Each of these colors helps it to blend in well with the reef. Trumpetfish eat other fish, a feat that is possible because a trumpetfish’s mouth can expand to many times the diameter of its body.

These fish hunt by hanging vertically next to sea fans and branching coral. They mimic the coral’s gentle movements and wait for unsuspecting prey. Look for well-camouflaged trumpetfish hovering motionless on reefs across the Caribbean.

Sand Diver

Sand divers (Synodus intermedius) can be exceptionally difficult to spot. They are a type of lizardfish, and like chameleons, they are masters of disguise. A sand diver can be so pale that it is almost white, or it can darken to mimic a colorful reef or sponge. If you manage to see a sand diver during a dive, gently fan water toward it. Eventually, it will hop to a new place on the reef and immediately adjust its colors to disappear against its background.

Banded and Foureye Butterflyfish

The banded butterflyfish (Chaetodon striatus) and the foureye butterflyfish (Chaetodon capistratus) are only two of the numerous species of butterflyfish found on Caribbean reefs. You can easily distinguish the banded butterflyfish by the black bars (vertical stripes) on its sides. In contrast, the foureye butterflyfish has pinstripe diagonal lines running across its body. The foureye butterflyfish’s most recognizable feature is two large spots near the back of its body, one on each side. These two spots mimic the appearance of eyes, giving the foureye butterflyfish its name.

Butterflyfish of all species can be distinguished from angelfish, which also have rounded, flat, disc-like bodies, by the length of their anal and dorsal (top and bottom) fins. Most angelfish have anal and dorsal fins that extend past the tip their tail fins, while most butterflyfish do not. Butterflyfish are usually seen in pairs fluttering above shallow reefs.

Gray, French, and Queen Angelfish

Angelfish are both beautiful and easy to find during a dive. While there are many species of angelfish throughout the world, the gray angelfish (Pomacanthus arcuatus), queen angelfish (Halocanthus ciliaris), and French angelfish (Pomacanthus paru) are among the largest and easiest to recognize.

The gray angelfish is a uniform gray color with a white snout and a yellow pectoral (side) fin. The French angelfish is also gray to black, but the scales on its sides are all bordered with a touch of yellow. The queen angelfish is a brilliant combination of blues, greens, and yellows and can be recognized by the round spot on its forehead, which looks like a crown if you apply a bit of imagination.

The larger angelfish, such as these, all have pectoral and anal fins that extend well past their tail fins. If an angelfish were rotated so that it was tail-down, the silhouette of the fish would appear much like the stereotypical angel shape. This helps to distinguish angelfish from butterflyfish.

Squirrelfish

Squirrelfish (Holocentrus adscensionis) have spiky fins and big dark eyes. They are nocturnal and use their big, sensitive eyes to hunt for prey in minimal light. You can typically find these night owls loafing around in dark areas of the reef during the day, but you can see them in the open on night dives. A variety of squirrelfish species can be found in the Caribbean, and while they all have distinctive features, most species have reddish bodies, silver or golden horizontal stripes, and big spiky dorsal fins.

Porcupinefish

The porcupinefish (Diodon hystrix) is a large, white pufferfish covered with long spines. Divers needn’t fear a porcupinefish’s quills—porcupinefish are slow-moving, docile giants with huge, doll-like eyes and wide mouths. Like other pufferfish, the porcupinefish can puff up by filling with water when threatened. The quick change in size not only startles predators, but it also makes the porcupinefish a difficult size and shape to eat. As a further defense, inflation causes a porcupinefish’s spines to protrude out perpendicular to its body.

Goliath Grouper

The Goliath grouper (Epinephelus itajara) is a gigantic, predatory fish that reaches up to 6 feet in length. This grouper can darken or lighten its colors and patterns to be camouflaged by its environment. Divers can watch it change colors as it swims between different parts of the reef or chases down a fish.

While the Goliath grouper is the largest grouper that divers are likely to see, there are many other grouper species on Caribbean reefs. All groupers have huge, downturned mouths and thick lips. You can see groupers in a variety of sizes, from a few inches to several feet, and in almost every imaginable color and pattern.

Spotted Drum

Spotted drum (Equetus punctatus) are exciting to find. Juveniles do not have spots, but they do have extremely long dorsal fins that flutter above and behind them as they make small movements. Adult spotted drums are mismatched—they wear both spots and stripes. Adults’ unusual patterns make them a great favorite among divers. The name “drum” was given to these and several other similar species because they can make a low resonance noise similar to the beating of a drum.

Blue Tang

Many divers recognize blue tangs (Acanthurus coeruleus) as Dori, the fish character from the Disney movie “Finding Nemo.” These small round blue or purple fish are a type of surgeonfish, so-named because of the small yellow spike where the tail meets the body. This extremely sharp spine can be thought of as a surgeonfish’s scalpel. Like many fish, blue tangs can darken or lighten to provide camouflage with their surroundings. Blue tangs are frequently seen in schools grazing on plant life. Divers frequently observe large groups of blue tangs moving slowly over the reef as they snack on bits of algae.

Peacock Flounder

The peacock flounder (Bothus lunatus) looks like it is swimming on its side—which is exactly what it is doing. A peacock flounder begins life as a normal, vertical fish with eyes on both sides of its head. But during development, one eye migrates through its head and the fish flattens and begins to swim on its side. The fin protruding vertically from the fish’s back is actually its pectoral (side) fin. Divers most commonly observe peacock flounders lying camouflaged in the sand. They can turn to a nearly white shade or darken their colors to brilliant hues. When not camouflaged, they have noticeable bright blue rings reminiscent of the pattern on a peacock’s feathers.

Scrawled Cowfish

The scrawled cowfish (Acanthostracion quadricornis) is one of the several species of cowfish found in the Caribbean. Cowfish is a type of boxfish and can be recognized by the cow-like horns above their eyes. These fish are docile and relatively slow-moving unless threatened. You can identify a scrawled cowfish by the characteristic pattern of wiggly, iridescent blue lines covering its yellow body. These markings help the fish blend in with the reef around it.

Sharpnose Pufferfish

The sharpnose pufferfish (Canthigaster rostrata) is a tiny pufferfish with beautiful coloring and a starburst of blue lines radiating out from its golden eyes. Like all pufferfish, the sharpnose puffer can inflate itself with water when threatened. This is a defensive behavior that surprises predators and causes the fish to appear larger than it is.

Yellow Goatfish and Yellowtail Snapper

Many divers confuse yellow goatfish (Mulloidichthys martinicus) and yellowtail snapper (Ocyurus chrysurus) because of their similar coloration and the fact that they might school together in large groups on shallow reefs.

Goatfish, including the yellow goatfish, have whiskers or barbels underneath their chins. These are fleshy appendages that they use to hunt for food hidden in the sand. In addition to the yellow goatfish, divers might also see the spotted goatfish (Psuedoupeneus maculatus), which has similar barbels and is either white with three dark spots on its sides or a marbled pinkish-red color.

Yellowtail snapper, like yellow goatfish, can also be seen hovering in schools over the reef. They sometimes form mixed schools with the yellow goatfish. While similar in appearance, yellowtail snapper does not have the barbels characteristic of goatfish.

White Spotted Filefish

The white spotted filefish (Cantherhines macrocerus) is a large, flat fish with a protruding snout. This fish is easy to identify by its bright orange color. Like many other fish species, it can darken and lighten. The white spotted filefish can darken to nearly black with large white spots. This color change is almost instantaneous and is exciting to watch on a dive. All filefish have a sharp spine on their foreheads at the beginning of their dorsal fin. Filefish can extend this spine when threatened, making them more difficult for predators to eat.

Yellowhead Jawfish

The yellowhead jawfish (Opistognathus aurifrons) is a tiny, fairy-like fish with a bright yellow head, iridescent white body, and huge, cartoonish eyes. Yellowhead jawfish burrow holes in the sand near reefs. Divers can find them poking their heads out of their hiding holes or hovering a few inches above them.

Great Barracuda

The great barracuda (Syphraena barracuda) has a mouth full of sharp, pointed teeth. Its silver body with occasional black spots provides camouflage with just about everything, and it is common to find great barracuda hunting both along the surface of the water and over the reef.

These fish are attracted to shiny, reflective objects that mimic the effect of light bouncing off their prey, but they do not pose much of a threat to divers. The great barracuda are designed to be effective hunters, and it is fascinating to watch them charge through schools of smaller fish and snap up prey.

Lionfish

Lionfish (Pterois volitans), while beautiful, are an invasive species from the Indo-Pacific that have become a common sight in the Caribbean. With no natural predators in the Caribbean, lionfish populations have skyrocketed over recent years. Lionfish feed on young reef fish that have not yet had the opportunity to reproduce. This has decimated reef fish populations in many areas of the Caribbean.