Aulostomus chinensis is a medium-sized fish which grows up to 80 cm in length. Its body is elongated and compressed laterally, with a long, tubular snout which has a small barbel at its inferior extremity. The protusible mouth can be extended forward to catch prey. On the top posterior part of the body, the dorsal fin is composed of two parts, the first anterior is a set of isolated spines and the second is a small ray fin. This latter fin is similar in shape to the anal fin which is just under. The pelvicfins are located in the middle of the body and are small, with one basal black spot.
The body coloration can be uniform or mottled in a range of grey, brown, or dark green. Some fish are uniformly bright yellow. The rear part of the body is normally black with white dots. Two black spots are present on the tail. The compound set of the long caudal peduncle and the caudal fin is yellowish, whatever the fish coloration. Caudal fin usually has two round black spots, at least one black spot occurs on the top and sometimes a second spot on the low part.
This species is also known as Trumpet, Pacific Trumpetfish, Painted Flutemouth and Tahiti Cornet Fish.
Aulostomus chinensis is a benthopelagic species found in protected waters of coral and rocky reef habitats, living at up to 200 m depth (Bowen et al. 2001). It spawns in pelagic waters and moves to the epipelagic zone as a small juvenile. Larger juveniles inhabit seagrass and coral areas. This species is a poor swimmer and relies on camouflage and stealth to catch prey. Juveniles have been measured at 11.6-15.1 cm length and 71-116 days old. Both juveniles and adults utilize habitat from shallow waters to the continental slope, and dispersal is not thought to be a restricting factor for the species.
Other trumpetfish species have been observed attempting to blend in with large herbivorous reef fishes as camouflage for taking their smaller prey fish (Aronson 1983).
Trumpetfish are carnivores, feeding on small fish and invertebrates. While most of the fish trumpetfish eat are quite small, like gobies and blennies, they have been known to consume fish as large as smaller grunts and surgeonfish. Rather than using sheer speed or agility to catch prey, trumpetfish have developed several specialized feeding techniques. One is to camouflage themselves using their chromatophores vertically amongst sea whips or sea fans and either remain stationary or slowly drift with the current around the bases of these gorgonians. When a prey item presents itself, the fish opens its mouth wider than the diameter of its own body, facilitated by elastic mouth tissues, creating a vacuum that sucks the prey into the trumpetfishes mouth (flmnh.ufl.edu). Another specialized hunting technique involves the trumpetfish slowly swimming behind a large herbivorous fish, using the larger fish as camouflage, then coiling its body into an s-shape and rapidly lunging at prey when an opportune moment to strike presents itself. Trumpetfish seem to select a shadowing fish based on color: red-brown trumpetfish tend to shadow brownish fish like grouper, blue-grey trumpetfish shadow schools of blue fish like blue tang, and occasionally even scuba divers (oceana.org). Various larger grouper, snapper, and moray eels are known predators of trumpetfish.
The intricacies of trumpetfish reproduction are not well studied, but it is known that they use their chromatophore color changing abilities to conduct elaborate mating display rituals. These courtship rituals occur near the surface, then, as in their close relatives the seahorses, the burden of caring for the eggs is given to the male, who fertilizes them and carries them in a special pouch until they hatch (marinebio.org).
This species is known to be abundant.
Its is an aquarium fish.