Yellowhead Angelfish

Habitat: Natural geographic location:
   The Yellowhead Angelfish or Coco's Pygmy Angelfish are found in the Southeastern Indian Ocean; the Cocos-Keeling Islands and Christmas Island. The were first collected in the Cocos-Keeling Islands by Smith-Vaniz and Randall in1974, and named within a year. Smith-Vaniz and Randall also described Colin's Pygmy Angelfish C. colini from the same area at that time.
   The species is abundant in their natural habitat and seen singly or in a small group. It is observed among coral and ruble on the steep outer reef at the depths between 49 - 246 feet(15 - 75 meters), and on occasion it can be found at 26 - 33 feet (8 - 10 meter) at drop-offs.

Status:
   These fish are not listed on the IUCN Red List.

Description:
   The Yellowhead Angelfish or Coco's Pygmy Angelfish is described by its common name 'yellowhead', reflecting this bold aspect of its appearance.

Yellowhead Angelfish (Juvenile) Note the black spot(s) on soft portion of dorsal fin Photo Courtesy: Hiroyuki Tanaka

   It is yellow on the anterior 1/3 part of body and blackish blue posteriorly. There is a blue ring with black spots around eye and the cheek spine is bluish. The caudal fin is yellow and the peduncle is brownish. Dorsal and anal fins are blackish blue with deep blue margins while the pectoral and pelvic fins are yellow.
   It is slightly similar and very close to Hotumatua’s Angelfish C. hotumatua from the Southeastern Pacific, but the latter has a prominent black spot just behind eye, and has a yellowish to deep brown body. It is also somewhat similar to the Bicolor Angelfish C. bicolor, but is not a close relative. The latter can easily be differentiated by its eye band and by the blue coloring of its body.

Length/Diameter of fish:
   Adults reach 3.5 inches (9 cm).

Maintenance difficulty:
   To acclimate this fish when you first acquire it, you need to help it feel secure. Do this by providing multiple hiding places and keep it with a few non-aggressive but active fish such as flasher wrasses or chromis damsels. They can entice it to come out and explore, also encouraging it to accept food. Once it is successfully acclimatized it will become a very hardy fish. As it may harm polyps of some stony and soft coral species, so it is not recommended for reef-type aquariums.
   Most of the Centropyge members are very colorful but unfortunately are rather difficult to keep for a long period, and on occasion they suffer from “ich” (white spot disease) and other infectious diseases. They can be treated successfully with medical care or copper drugs, but some species hate sudden changes of water including PH and temperature, and any drug treatment. In the wild a cleaner wrasse (Labroides sp.) will help them by taking parasites from their bodies.

  Diseases that marine angelfish are susceptible to:
Marine Ich (white spot disease), Marine Velvet, and Lymphocystis (a viral infection).

Foods:
   The Yellowhead Angelfish are omnivores. Provide a varied diet. Meaty foods, dried flakes, shrimps, frozen prepared diets for sponge and algae eaters, and tablets are acceptable. Feed frequently at first with various foods, including algae. Feed at least twice a day, but for a tiny juvenile provide it with foods three to four times everyday.

Maintenance:
   Once this angelfish is successfully acclimated it will become a hardy fish. No special care is needed, it takes a variety of foods and is easily kept in a captive environment. It needs many crevices to hide even if it is an adult and it is quite active, so needs plenty of room to swim. Frequent water changes are not necessary, rather normal water changes at 10% biweekly or 20% monthly are fine. Sudden massive water changes can cause trouble.
   For more information see, Marine Aquarium Basics: Maintenance

Aquarium Parameters:
   This is an active fish so needs lots of space for swimming. It also needs many crevices to hide in even as an adult. An aquarium well decorated with rocks/ corals will providing it with many places for retreat
Minimum Tank Length/Size:
   A minimum 50 gallon (189 liters) or more.
Light: Recommended light levels
   It can be kept under strong lights or in a dimly lit aquarium.
Temperature:
   This species lives in tropical areas. Temperatures between 75 -79° F (24 - 26° C) will serve them well, but temperatures higher than 84° F (29° C) or below 72 ° F (22° C) would not be good.
Water Movement: Weak, Moderate, Strong
   Water movement is not a significant factor. It can tolerate a rather stronger flow, but slow-moving
water is preferable.
Water Region: Top, Middle, Bottom
   It is rather a quick swimmer around the rocks or corals, and also it will venture to the surface for foods when it is well acclimated.

Social Behaviors:
   The Yellowhead Angelfish or Coco's Pygmy Angelfish is recommended for fish only community aquariums. The tank should be well decorated with rocks/ corals with many hiding places even if it is an adult. It is also said to be a reef safe fish as it does well in a coral-rich tank with sessile inverts, but it may eat some species of hard and soft corals. However not every fish is going to damage corals, the behavior of each individual fish will be different. If you do want to keep it in a reef observe its behavior towards the corals closely, removing it to a fish only tank if it tends to pick at them for any length of time.
   A group of several individuals of this angelfish can be kept successfully but they need a lot of space for swimming and many hiding places. It is an active fish and can get along together with more aggressive species. It can be kept with larger and rather territorial angelfishes like Pomacanthus and Holacanthus. Other angelfish such as members of Centropyge, Apolemichthys, Genicanthus, Chaetodontoplus and Pygoplites could be good tank mates. Smaller cardinalfish, gobies, tilefish, butterflyfish, fairy basslets, fairy and flasher wrasses, etc. are also good candidates; as are wrasses of a variety of genera. Small but very territorial fishes like dottybacks should be avoided in the same tank.

Sex: Sexual differences:
   No sexual difference in color is noted, but the dorsal and anal fins are reported to be more elongate in males than in females.

Breeding/Reproduction:
   The Yellowhead or Coco's Pygmy Angelfish has not been cultivated in any laboratory yet.
   In their natural habitat, the pygmy angelfish form a harem dominated by one large male with between one and four smaller mature females and up to nine juveniles. At dusk during the lunar month the male will conduct an elaborate mating ritual and then spawn with each of the females individually. They are pelagic spawners, each pair will rise up several feet above the reef and release the eggs and sperm together directly into the water column. The eggs are fertilized and continue to rise up to the plankton rich surface.
      For more information see, Marine Fish Breeding

Availability:
   The Yellowhead Angelfish or Coco's Pygmy Angelfish is rather rarely available at retailers and commands a high price for Centropyge species, starting at least $160.00 USD. The specimens that are available range between 2 - 3 inches (5 - 8cm) in length. On rare occasions juveniles less than 1 1/4 inches (3 cm) are obtainable.

"The first time I saw this lovely fish was at a retailer in Tokyo around 1990, but it was very rare. The species is still a rare fish and is much sought after by aquarists. It commands a high price of at least US $160.00. Many reef-keepers wish to keep it in a mini reef and it will be a great addition to any type of tank."... Hiroyuki Tanaka