Handy Pocket Guide to Tropical Coral Reef Fishes. Gerald Allen

javanicus

      Family: Muraenidae

      There are dozens of moray eel species on tropical coral reefs, but most are shy and seldom seen. They inhabit the endless cracks and fissures that riddle the reefs surface. The Giant moray is a notable exception that is often sighted by divers and has a particularly vicious appearance. Growing to a length of at least 2.2 metres and 30 kg weight, it is the largest moray eel living in the vast Indo-Pacific region. Like most morays, its jaws are equipped with numerous sharp fangs, which are normally used for capturing fishes or crustaceans. However, they can inflict nasty wounds on careless divers. For this reason it is not advisable to blindly probe deep crevices with your arms while diving, possibly in search of shells or lobsters. Nor is it advisable to spear large eels. They can easily spin off a spear and may vent their anger by biting savagely. In contrast, unprovoked specimens are usually docile and will allow divers to photograph them at close range or even feed and pet them.

      Striped Catfish

      Plotosus lineatus

      Family: Plotosidae

      Catfishes are usually thought of as being freshwater inhabitants, but are prominent in marine waters of Southeast Asia. Although most are confined to estuaries and turbid coastal waters, the Striped catfish is commonly encountered on coral reefs. Juveniles are most seen. They typically form aggregations which contain up to several hundred fish massed tightly together, with individuals actually in contact with one another. The aggregation takes on the appearance of a much larger creature or even inanimate objects, reducing the chances of predation. Large catfishes have few enemies due to their very venomous fin spines. Extreme care should be exercised when handling them as the puncture wounds are excruciatingly painful.

      There is scant reproductive information on the Striped catfish. Males build nests under rocks or large pieces of debris and guard the eggs. The species ranges from the Red Sea to Samoa. Maximum size is 32 cm.

      Spotfin Squirrelfish

      Sargocentron cornutum

      Family: Holocentridae

      Although very abundant on coral reefs, squirrelfishes are seldom noticed by snorkellers. They remain hidden deep in the shadows of caves and crevices during daylight hours. Shortly after sunset they begin to emerge for nocturnal feeding. Because most of the reefs fish occupants are active during the day many invertebrates, particularly crustaceans and echinoderms, have evolved a strategy to avoid them by coming out to feed at night. Squirrelfishes have adapted night-time feeding to take advantage of this behaviour. They mainly consume crustaceans, particularly small crabs and shrimps.

      Squirrelfishes are easily recognised by their red coloration, coarse scales and large eyes. Another remarkable feature is their ability to produce clearly audible "clicking" sounds, believed to function as a form of communication between members of the school. Most species, such as the Spotfin squirrelfish, are less than 25 cm when fully grown, but the largest attains 45 cm.

      Trumpetfish

      Aulostomus chinensis

      Family: Aulostomidae