Perhaps the group
most familiar to aquarists is the angelfish family, and this
seems to be denied by no one. Here I introduce a rare color
morph of Centropyge potteri from the Hawaiian Islands
that is entirely blue-black on its side. Let's first discuss
some background information on the Centropyge genus,
and then we'll touch on this recently discovered unusual color
morph of Centropyge potteri.
The Genus Centropyge
The Family Pomacanthidae
includes seven genera (Randall, 2005) with some 88 recognized
species that dwell mainly on Indo-Pacific coral reefs. The
family is popularly known as angelfishes (or marine angelfishes)
worldwide. Their graceful colors and non-belligerent behavior
makes them much sought-after by aquarists and divers everywhere,
and they always fascinate not only beginners but veterans,
as well as many ichthyologists. Richard L. Pyle has reclassified
the group and made some changes. According to the most recent
study the genus Paracentropyge was reclassified into
the genus Centropyge, and then the species boylei,
multifasciata and venusta were shifted from
Paracentropyge to Centropyge. Also Frank Schneidewind
of Germany wrote a scientific paper describing Centropyge
flavicauda and C. acanthops as junior synonyms
(= same species) of C. fisheri, which was long thought
to be an Hawaiian endemic, and his concept is now widely accepted
by most ichthyologists. A new Chaetodontoplus species
was described as C. vanderloosi by Allen & Steene,
2004 from Papua New Guinea, and also Centropyge abei
was published by Allen, Young & Colin from Sulawesi and
Palau in 2006.
Centropyge is probably the most
popular genus both in the aquarium trade and in the field,
and its species often are called the Pygmy Angels due to their
small size, rarely exceeding 10cm. They tend to retire or
dash into crevices when danger approaches. They dwell in warm
waters of the Indo- west Pacific and the Atlantic Oceans,
being absent from only the eastern Pacific. Some species are
distributed widely in the Indo-West Pacific, yet some are
restricted to very small areas or even to a single island.
Centropyge are commonly mimicked by other fishes.
Three species are mimicked by the very similar juveniles of
surgeonfishes Acanthurus pyroferus or A. tristis.
Also, C. nox is mimicked by the very similar-looking
dottyback, Manonichthys paranox. Some species differ
in coloration depending on sex, but this difference may be
minor, while C. flavissima has an ocellus
on its sides in its juvenile stage. Centropyge flavissima
has two distinct color morphs; the Pacific variety has a blue
eye-ring but those from the Indian Ocean lack it entirely.
Many variations appear among individual species, and we often
see such varieties in C. bispinosa, which is red to
blue, whitish grey, entirely black or even orange or yellow.
Centropyge loriculus also has many variations; typically
red with five bars but some (especially those from the Marquesas
Islands, southeastern Pacific) completely lack the black except
on their fins. The Hawaiian Flame Angelfish is sometimes called
the "Ultra Flame" when it is deep red overall, but
this case is rare in Hawaii; most of them have a pattern similar
to other Pacific populations.
Members of this genus can easily be found at local fish stores
and are usually sold at lower prices than larger angelfish
species. Many are shipped from the Philippines and Indonesia
but some rarities come from the far island group, and they
typically command a higher price. Recently, some species have
been aquacultured and will be exported to angelfish enthusiasts;
these include C. resplendens, C. loriculus,
C. interrupta, C. flavissima, C. fisheri,
C. multicolor and even C. debelius. Many species
of Centropyge are hardy and eat well in captivity,
but several species refuse any food offered and are too timid
and retiring to thrive in captivity.
The genus now includes 32 species as shown in the following
Centropyge debelius was named after a famous diver,
Helmut Debelius. Centropyge woodheadi was deleted because
of its synonymy with C. heraldi. In addition, a probably
undescribed species was found off the coast of Western Australia
around the Rowley Shoals. Many natural hybrids have been discovered
and one of the most popular is the cross between C. flavissima
and C. vrolikii. For further information on the Centropyge
genus, the reader is referred to Henry Schultz' article, "What
a Darling Little Angel: The Genus Centropyge."
This species is typically yellow-orange
with a dark area that covers much of its body and has several
dark blue vertical bars on its entire body. It is endemic
to the Hawaiian Islands, the area northwest of the Hawaiian
Islands (Midway) and Johnston Island (south of Hawaii; rare).
It is a shallow water species that can usually be seen at
a depth of as little as one meter. The species occasionally
forms a harem, usually containing two individuals - one male
and its mate, and is also known to form groups of up to three
to four individuals in nature. Centropyge potteri has
no close relative in the genus and is distinctly colored.
It rarely exceeds 10 cm in length and is popularly called
the Potter's Angelfish or Russet Angelfish.
I have seen pairs on reefs in Kaneohe Bay several times,
southeastern Oahu and a single specimen that was swimming
along the wall of a yacht harbor in the bay while I was snorkeling.
Four shops in Oahu displayed many individuals of this lovely
angelfish at low prices, and most individuals sold at shops
are less than 8cm long. Some refuse any kind of food offered
in the aquarium, but most learn to accept many artificial
An Unusual Blue Morph
Some five years ago an unusual specimen
with a blue-black body was shipped from Hawaii. It was caught
at a depth of more than 60 meters off the Kona Coast, Hawaiian
Island. Two similarly-colored specimens were captured by divers,
and one of them luckily was exported to Tokyo (and another
went to the mainland USA). I saw the individual for the first
time at a shop in Kyoto in February of 2003. It was not for
sale but was displayed in a large reef tank with massive live
corals, other invertebrates and a few small, non-aggressive
fishes. It was a large, mature fish, some 10 cm long and was
eating well. I took several shots, two of which are shown
here. It is entirely a brilliant blue with numerous black
bars on its side with no yellow area, and some black areas
can be seen centrally on its body. It was sold at a price
of ¥600000,- at first. The aquarist who got it sold it
to his friend, and finally the shop obtained it for display,
where it was not offered for sale.
The reason it is this blue color is not known, but such a
deep area is very dark, almost black, so it is possible that
these specimens' color could have helped them avoid enemies'
attacks. But I wonder why it stayed blue in aquariums for
over three years
Figure 1. Centropyge potteri, a blue-black
color morph, 10 cm in length, from the Kona Coast.
Figure 2 (left). Centropyge potteri in
its typical coloration, 5cm long. Figure 3 (right).
The same individual shown in Figure 1.
I greatly appreciate the shop in Kyoto,
EARTH, that kindly permitted me to photograph this black beauty
there, and also another shop in Osaka, BLUE HARBOR, whose
personnel led me to the shop for the first time.
All photos copyrighted and taken by Hiroyuki