Acanthurus nigrofuscus

Gold Polka Dot surgeonfish ( Acanthurus nigrofuscus )

Called The Gold Polka Dot surgeonfish ( Acanthurus nigrofuscus ), also Brown Surgeonfish, is a species of the family Acanthuridae.

Appearance

The Gold Polka Dot Surgeonfish has a longitudinally oval, laterally flattened body that is brown to olive color. In the region of the head, which accounts for about 15 % of the body, he has showy golden points. In this, the German name of the species is due. Dorsal and anal fin, which is blue lined, can be set up in posturing. The caudal fin is extended crescent- shaped. The body length is about 20 cm. The mouth is terminal, like all surgeonfish species and is provided with movable bristle teeth. This is an adaptation to the main food algae he rasp hard substrate.

When spawning fish prepare the body Coloration changes. The brown to olive color colored body is light brown, the fins take on a reddish color and it shows a yellowish spine strip.

Dissemination

The Gold Polka Dot Doctor fish is common in the Red Sea and tropical Indo-Pacific to Hawaii and the coasts of Japan and the Great Barrier Reef and settled there lagoons and outer reefs. It can be observed up to a water depth of 25 meters.

Nutrition

He eats thread and leaf algae from hard substrates and prefers doing red and brown algae and green algae in summer and winter. The food habits of this species is particularly well researched.

" A. nicrofuscus collected on the short days of winter fat reserves and thereby significantly improved his condition, although the type could significantly longer eat per day in the other seasons. The reserves are as lipids in two specific fatty tissue, the mesentery to the genital organs and paired triangular fat pockets above the anal fin - embedded. The stored fats have higher levels of triacylglycerol as eg Liver and muscle lipids, which serve as an energy store for other species of fish. It was found that A. nigrofuscus in winter much more fleshy green algae ... eats than in summer ... because at this time employing the growth phase of the respective algae and much less disturbing Aufsitzeralgen, bryozoans, detritus and Dioatomeen with their special flavors sit on the algae sprouts. In summer, the doctors have to resort to the inferior for them red and brown algae. The amendments of certain fatty acid levels in the doctor fish fats as a result of the green algae seizing people became aware of this previously neglected relationship food. Since A. nigrofuscus the gnawed in winter reserves during the Gonadenausbildung consumed in the spring again, this particular diet relationship is responsible for successful spawning phase in the summer. "

Behavior

The diurnal Gold Polka Dot Doctor Fish Doctor Fish is one of the species that are commonly observed in flocks. At reef sites of 800 meters in length have been counted swarms, which include 250 to 400 individuals. The Riffabschnitt is divided into a zone in which the fish reside during their feeding phases, and one which they use as a rest area during the night.

Special

How many has he of living exclusively from algae doctor fish species in his digestive tract symbiotic Mikroorganisamen, with which he is able to digest its food. 1985 was the bacterium Epulopiscium discovered fishelsoni by the Israeli scientist Lev Fish Elson of the University of Tel Aviv in the bowels of Gold Polka Dot doctor fish, which, with a length of up to 0.7 millimeters of one of the largest known bacteria.