Acanthochromis polyacanthus

Swallowtail Damselfish ( Acanthochromis polyacanthus )

The Swallowtail Damselfish ( Acanthochromis polyacanthus ) comes in the coral reefs of the central tropical Indo-Pacific, before around the Indo- Australian Archipelago. Its circulation area covers the coastal waters of Indonesia, the Philippines, New Guinea, the Solomon Islands, Vanuatu and Great Barrier Reef off northeastern Australia. He lives mainly on steep ledges at depths of one to 65 meters and feeds on zooplankton.

Features

Swallowtail damselfish are eleven to 15 inches long. The body length is 1.7 to 2.0 times the body height. In terms of their coloring they are highly variable. The Indonesian population is uniformly dark brown, almost black. In the Solomon Islands, a blue-green color form occurs, the dorsal and anal fins have a black outer edge. The animals on the Great Barrier Reef are gray blue with white abdomen and white tail fin. Juveniles are brown with a golden yellow stripe along the lateral line. Along the sidelines have Swallowtail damselfish 20 to 22 scales. The number of gill Reuse extensions is 21 to 23 The caudal fin is deeply forked.

Fins formula: Dorsal XVII/14-16, Anal II/14-16, pectoral 17-18.

Reproduction

Through observations in the aquarium and the reproductive behavior of animals is known. The fish are, like all damselfish substrate spawners, and glue their eggs in a cave or hidden niche on the wall. A clutch has only 30 to 80 very large for fish eggs. The eggs are guarded by the couple and with the fins befächelt to fresh water supply.

At a water temperature of 25 ° C hatch after 13 to 14 days fully developed juveniles, a pelagic larval stage or a yolk sac for nourishment during the first days after the missing slip. If the water temperature is 27 ° C shortens the incubation period of 11 to 12 days. Older reports, which feed on the young fish as the discus cichlid (Symphysodon ) of the epidermis of their parents, have not been confirmed. Juveniles reared separately from their parents developed completely normal. With a slip size of five to six millimeters they are to eat from day one in a position small planktonic crustaceans and their larvae.

In contrast to all other reef fishes and almost all other marine fish, the brood care behavior of the parents does not go out after hatching of juveniles, but they put it still continues for more than three weeks and guard and protect their young. This for coral fish almost unique behavior comes out in the dovetail groupers only in the unrelated white stripe Aalgrundel ( Pholidichthys leucotaenia ) in front ..