Chaetodon declivis, also known as the Declivis Butterflyfish and Marquesan Butterflyfish, is a real beauty in any aquarium and a striking, rare deepwater species that is one of the most durable aquarium butterflyfishes. He only comes from a small area of the Pacific Ocean in the area of Christmas Island.
The Marquesan Butterflyfish has beautiful orange coloration covering the dorsal half of the body, as well as a small orange mask covering the eyes. The bigger part of the body are white with black spots.
Chaetodon declivis is a bold species that tends to spend most of its time in the open. Unfortunately, they are not good candidates for the reef aquarium. The Marquesan Butterflyfish feeds on glass anemones and clean the live rock, however, it will also feed on some invertebrates living on the rock, like fan worms and coral polyps too. The diat in the wild are primarily consists of coral polyps, crustaceans, and algae.
Chaetodon declevis Burgess & Randall, 1978
Classification: Biota > Animalia (Kingdom) > Chordata (Phylum) > Vertebrata (Subphylum) > Gnathostomata (Superclass) > Pisces (Superclass) > Actinopterygii (Class) > Perciformes (Order) > Chaetodontidae (Family) > Chaetodon (Genus) > Chaetodon declivis (Species)
I find the Declivis Butterflyfish a relatively easy fish to acclimate to aquarium life. It eats many different kinds of food and asserts itself at feeding time, in a community tank. What many aquarists don't realize is that this fish, along with the Tinker's Butterflyfish, enjoy eating a bit of macro algae. Provide fresh algae or dried packaged sheets of nori or algae daily like you would a tang, and it will enjoy that fair.
As always with most butterflyfishes, it is best to put into quarantine in order to get it eating different foods, and to get it used to humans (as well as to be sure it is disease-free).
Marquesas Islands ( C.d.declivis) & Line Islands ( C.d.wilderi); 12 cm; scarce
Specimens sold at shops are all this subspecies C.declivis wilderi from Christmas Island, Line Islands in mid Pacific, and these cannot be found in Marquesas, so we should call it Wilder’s Butterflyfish, not Marquesan Butterflyfish; a subtle difference could be found between these two subspecies, however; the amount of dark area depends on specimens; very close to C.tinke i ; fortunately I could see it for the first time at a shop in Oahu, and it was just collected and brought back by Dr. Randall Kosaki, who described Centropyge nahackyi in 1989, we met just after his description; the specimen in a shop soon took foods offered in the tank (see right photo); very easy to acclimate and maintain in aquaria