Tropical fish in the South Pacific: Genicanthus bellus and Centropyge multicolor

Genicanthus Bellus Classen
Genicanthus bellus, 1975

During the 1970s Clem ran a commercial diving operation which specialized in collecting tropical fish for the aquarium trade. While in Tahiti he was credited with the discovery of two fish: genicanthus bellus and centropyge multicolor. We find out more about the discovery of both of these fish.

Can you tell us about what you were doing in Tahiti and your discovery of a new fish?

My diving in Tahiti was from 1973 to 1974. A little less than a year. There were very few other divers there, mostly French recreational divers, who dove with knives and spear guns. They were not collecting tropical fish. I was probably the only tropical fisherman down there at the time. I had my own setup with the compressor, scuba bottles, a boat, and complete dive gear. My routine was to wake up early in the morning and walk out to my boat, which was anchored in about four feet of water on the inside reef, right in front of a house that I rented. I would load up with the gear and then meander through the interior reef to the outer reef.

Clem Classen early 1970s
Clem, early 1970s

The best diving was on the outside of the reef, although there was some fishing on the inside. There were certain spots where the outside reef had a sheer drop-off. The top of the reef might have been at 25 ft. and the ledge would’ve dropped straight down – probably more than 1000 ft. The fish that I first discovered, the Genicanthus bellus – its normal habitat is more than 90 ft. Diving back then, I was diving on regular air, not mixed gas. We didn’t have dive computers. I carried a ceramic disc encased in its housing that absorbed gases at theoretically the same rate that your body did. There was a little meter and when it reached the red zone, it meant that you were in your saturation zone, and you’d have to not come straight up, but hang off at various depths to outgas slowly. The Genicanthus bellus had never been seen before. It took me two bottles to catch it.

Was this at 90 ft.?

I’m not sure what depth it was. It was definitely deep and it was on a sheer wall, a drop off. So I was able to catch it by forcing it up towards the surface. As the fish got higher and higher, its air bladder expanded and it became difficult for it to swim back down. I was able to catch it that way. It did take me two bottles. I ran out of air on the first one. Then I went back down and found it again – struggling to get back down – and caught it.

I sent it off to Jack Randall at the Bishop Museum to identify, and he’s the one responsible. He’d asked me if I wanted it named after myself and I said, no, and it was named Genicanthus bellus.

And did you know when you saw it – when you were diving – that it was something special?

Yes. I’d never seen anything like it before. I didn’t know if it was a new species, but it was very beautiful. A very unusual fish. The genicanthus is from the angelfish family. It’s a very good aquarium fish. I was diving solo, so I was the only person out there diving, which was probably a little bit reckless. Most people would dive in pairs, but as fish collectors, if we did dive in pairs, we would go in opposite directions so we didn’t dive within sight of each other.

And this was collecting fish for the Los Angeles aquarium market?

Well, one of our customers was in Los Angeles. Some of our customers were in other parts of the United States, and we even shipped out to Germany. We were probably the only shippers who could reach Europe. The fish out of Tahiti were shipped to Hawaii, reacclimated in the aquarium, and then shipped out from Hawaii to reach Frankfurt. The fish were put into special bags that we inflated with pure oxygen, one fish per bag. And those were put into Styrofoam insulated containers and we would load those into LD3 containers, which is a special container that fits in the belly of the plane. The shipper would get a better freight rate that way. We would ship out these boxes of fish, sometimes 20 or 30 boxes at a time.

Centropyge multicolor, 1974

Can you tell us more about the other fish, the multicolor angelfish, that you also discovered?

It’s an angel fish related to Potter’s angel, which is more common in Hawaii and actually endemic to Hawaii. And this one is small, maybe three inches long. Very difficult to see. It’s generally found in 60 to 100 ft. depths. And down there, once you pass 15 ft., the color red is all gone. You don’t see red at all. So what your eye sees is brown, and this fish is purple, a reddish purple. It blends in perfectly down there. It’s easy to miss. The reason I actually set up the Tahiti operation was because of the flame angel – very common down in Tahiti. Extremely rare everywhere else in the world. The operation was centered around that. The diving back then was incredible. The interior reefs were pristine, gorgeous, and the outside reefs were virtually untouched.

Taxonomic details

Genicanthus bellus

Genicanthus bellus
Ornate angelfish
Randall, 1975

Occurences
BPBM 16840 Tahiti: Paea – outside barrier reef; vertical drop-off [Clemens Classen]
BPBM 16841 Tahiti: Paea – outside barrier reef; vertical drop-off [Clemens Classen]

Domain: Eukarya
Kingdom: Animalia
Superphylum: Deuterostomia
Phylum: Chordata
Subphylum: Vertebrata
Superclass: Gnathostomata
Subclass: Actinopterygii
Order: Perciformes
Suborder: Percoidei
Family: Pomacanthidae
Subfamily: Pomacanthinae
Genus: Genicanthus
Species: bellus

Notes:
Located in Eastern Indian Ocean: Cocos-Keeling Atoll. Pacific Ocean: Philippines, Palau, Guam, Cook Island and the Society Islands. Recently reported from Tonga.

Max length 18cm. Schools found along steep current-swept outer reef drop-offs from 80 to 360 ft. Forms groups of 3-7 individuals. Feeds on plankton. Rarely exported through the aquarium trade.

Centropyge multicolor

Centropyge multicolor
multicolor angelfish
Randall & Wass 1974

Occurrence
BPBM 17243 Tahiti: Paea – outside barrier reef; vertical drop-off [Clemens Classen]

Domain: Eukarya
Kingdom: Animalia
Superphylum: Deuterostomia
Phylum: Chordata
Subphylum: Vertebrata
Superclass: Gnathostomata
Subclass: Actinopterygii
Order: Perciformes
Suborder: Percoidei
Family: Pomacanthidae
Subfamily: Pomacanthinae
Genus: Centropyge
Species: multicolor

Notes:

Located in the Central Pacific; Marshall Islands, Marianas, Palau, Society Islands, Fiji, Cook Islands and the Hawaiian Islands.

Max length 9cm. A dwarf angelfish with rich colors. First collected by Clemens Classen in Tahiti in 1974, and then quickly followed by Dr. John Randall at the Majuro Atoll in the Marshall Islands, and then Dr. Gerald Allen only months later at Enewetak Atoll also in the Marshall Islands.

A deep dwelling fish at depths of 65-380 ft. but also on reef drop-offs at shallower depths. Found in groups of 4-10 and by themselves on reef walls. Has been well-cultivated for the aquarium trade.

Further reading

More information on the official taxonomic records for both fish can be found below:

http://www2.bishopmuseum.org/natscidb/

Allen, G. R. 1980. Butterfly and angelfishes of the world.

Further reading on the multicolor angelfish:

Two New Pomacanthid Fishes of the Genus Centropyge from Oceania’ in Japanese Journal of Ichthyology Vol. 21, No. 3, 1974.

https://animal-world.com/multicolor-angelfish/

Manta Ray Diving on the Kona Coast

Last Updated on February 16, 2025 by Angus.
Manta Ray Kona Hawaii Big Island Horizon B&B
Photo credit: Horizon Guest House

The Big Island of Hawaii is famous for many things but perhaps one of the most popular and unique attractions is the manta ray night dive. Don’t worry if you’re not a certified diver – snorkelers can still experience the thrill of being close to these majestic creatures.

Why are manta rays so special?

The manta rays inhabiting the Kona Coast are reef manta rays, one of the largest species of manta rays in the world. These amazing creatures can grow in size to anywhere between 12 and 18 feet. Life expectancy can be anywhere up to 50 years.

Manta rays are filter feeders – they survive on plankton. By gliding through the ocean with their giant mouths open they filter the plankton out of the water. The reef manta rays are so-called because they prefer to stay close to the coast of the Hawaiian islands.

Did you know? Manta rays derive their name from the Portuguese and Spanish word for ‘mantle’ which is a blanket-shaped trap historically used to catch this type of fish.

Manta Ray Night Diving Kona B&B Horizon
Photo credit: Horizon Guest House

Why night dive with the mantas?

A night dive with mantas is essential in order to see these great creatures up close. Their prey, the plankton, are light sensitive and are drawn to the glow of dive flashlights – providing a perfect meal for the manta rays.

This creates the perfect environment for a close encounter with the mantas. If you choose to scuba you will be weighted so that you can sit comfortably on the sea floor around a collection of dive lights, a kind of ‘campfire’, while the mantas circle above – almost like a scene out of ‘Close Encounters of the Third Kind’.

If you choose to snorkel you’ll have a very similar experience at approximately 30 feet above. Snorkelers gather around a floating raft with bright lights that also attract the mantas. The dive itself lasts for approximately 45-60 minutes. The mantas will swim very close, but don’t worry they’re too focused on enjoying their meal to worry about you!

Fun fact: Don’t be afraid! The manta rays are large but harmless. They do not have stingers, barbs or teeth.

Where are the mantas?

There are two principal dive sites. The main dive site is near the Kona Airport runway, about a 25-30 minute boat trip from Honokohau Harbor. In this location there can be as many as two dozen mantas congregating during a night dive. The other, less well-known site is near the Sheraton Hotel in Keauhou Bay.

Several companies run charters out to these dive sites – we recommend Big Island Divers https://bigislanddivers.com/

Sustainable manta ray snorkeling

If you prefer a less crowded snorkel experience then Manta Ray Advocates might be for you. They adhere to strict guidelines to make sure the manta rays don’t get disturbed by your presence. They approach the mantas from the beach, an eco-friendly alternative to sightseeing boats. Experience the thrill of the manta rays in a safe, private setting, and in a small group (each group is limited to 6).

2020-BLOG-Featured-Image-Facing-Extinction-1-400x250
Photo credit: mantarayadvocates.com

Did you know? In Hawaii the manta rays are a protected species – it is illegal to hunt or fish them. Hawaiian mythology depicts the manta as catching the setting sun in their mouths before swimming to the other side of the island to deliver the sunrise. Find out more about manta ray preservation and protection from Manta Ray Advocates https://mantarayadvocates.com

What else might I see when diving on the Kona Coast?

Open Ocean Ray Kona Hawaii Horizon Guest House
Open ocean manta - Chill Ray / Photo credit: Horizon Guest House

While it’s almost guaranteed* that you’ll see reef mantas during the night dive, there’s plenty to see during the day too. If you’re lucky you might see the pelagic or open ocean manta. I was lucky enough to spot one (see above), an individual that had never been photographed before.

*Big Island Divers offer either a 50% discount on a seat for another manta charter, or a 100% discount on standby availability seats for another one-tank manta charter, if no mantas are seen during a dive.

Did you know? Mantas, like humpbacks, have individual markings. These markings are catalogued by marine biologists. Let me know if you see the manta I photographed – it’s officially named ‘Chill Ray’.

Open Ocean Ray Chill Ray Kona B&B Horizon
Open ocean manta - Chill Ray / Photo credit: Horizon Guest House

Whether scuba or snorkeling you’ll see plenty of yellow tang (a surgeon fish).

Yellow tang Kona Hawaii Horizon Guest House
Yellow tang / Photo credit: Horizon Guest House

Almost as equally prevalent is the raccoon butterfly fish.

Raccoon butterfly fish
Raccoon butterfly fish / Photo credit: Horizon Guest House

Don’t forget the turtle! An encounter with a sea turtle is an unforgettable experience.

Sea turtle Kona Hawaii Big Island
Sea turtle / Photo credit: Horizon Guest House

When scuba diving at the Kona Airport dive site you may encounter Hawaiian garden eels. These eels rise out of the sand to feed but keep part of their body in their burrow in order to instantly pop back down when threatened.

Anthias damsel fish Kona Hawaii Big Island
Bi-color anthias and black and white damsel fish with Hawaiian garden eels in the background / Photo credit: Horizon Guest House

There is also plenty of cave diving on the Kona Coast – some near the manta dive sites. Here you’re likely to see fish that feed at night like the menpachi, see below.

Menpachi Kona Hawaii Big Island Horizon B&B
Menpachi with a solitary cleaner wrasse / Photo credit: Horizon Guest House

You may also see soft coral on cave ceilings and walls.

Soft Coral Kona Hawaii
Soft coral / Photo credit: Horizon Guest House

If you’re lucky you might even see a ‘ruby’ among the coral – a flame angelfish.

Flame angelfish Kona Hawaii
Flame angelfish with kole surgeon / Photo credit: Horizon Guest House

Count yourself extremely lucky if you spot our endangered monk seal. Rarely seen anymore, but it’s still possible.

Monk Seal Kona Hawaii Horizon Guest House
Monk seal / Photo credit: Horizon Guest House

Don’t forget to book your dive trip early – the manta ray dives and snorkel tours can book up fast.

To make a reservation at Horizon Guest House click the Book Now button below.

Author: Angus Meek

Diving on the Big Island

White Sea Urchin
The rare white sea urchin. Kona Coast. 40 ft depth. Photo credit: Clem Classen

Diving in Hawaiian waters, whether it’s snorkelling or scuba, has always been regarded as one of the must-do diving experiences. But if you have ever dived in other locations around the world it may not be what you expect… *hint: it’s even better than you could imagine..

Nudibranch Big Island Horizon Guest House
Nudibranch. Big Island. 1 ft depth. Photo credit: Clem Classen

What's different about diving in Hawaii?

The Hawaiian Islands are one of the most remote areas on earth. Not only are the islands isolated but the main Pacific Ocean currents do not intersect around the Hawaiian Island chain. This has meant that there hasn’t been the same current drift that other islands have had, and as a result the islands don’t have the same level of bio-diversity as some of the other island chains. In fact, we are missing the large amount of invertebrates found in other tropical waters.

Soft corals Kona Coast Horizon Guest House Hawaii
Soft corals. Cave diving, Kona Coast. 30 ft depth. Photo credit: Clem Classen

Around all the Hawaiian Islands are steep drop-offs into deep water and because of this there are very few shallow reefs to harbor and protect the sensitive sea fans and soft corals.

Juvenile Frog Fish
Juvenile frog fish. Kona Coast. 30 ft depth. Photo credit: Clem Classen

Having been a professional diver for many years, I was astounded when I first dived other tropical locations. When I dived in French Polynesia, in particular the Tahitian Islands, I was amazed to see the variety of marine life. Vast fringing reefs formed lagoons rich with colorful clams, soft corals, sea fans, shrimp and crabs.

Green Turtle Honaunau Big Island Horizon BnB
Green turtle. Honaunau, Kona Coast. 15 ft depth. Photo credit: Clem Classen

So what IS special about diving in Hawaii?

The Hawaiian Islands not only have indigenous and unique marine life, but of the known 24,000 species of fish in the world:

  • The Hawaiian Islands are home to over 1,100 species
  • Among this number, 149 are native to Hawaii (these include the Hawaiian Whitespotted Puffer and the Potter’s Angelfish)

Diving along the Kona Coast means you’ll be able to see over 40 percent of these native species of fish, almost all of the native corals, as well as the Hawaiian green sea turtle, and all just minutes from entering the ocean – and in as little as 5 feet of water!

Flame Angel Big Island Hawaii
The rare flame angel fish. Big Island. 40 ft depth. Photo credit: Clem Classen

Safer Diving

Diving in the Hawaiian Islands is some of the safest diving in the world. There are no sea snakes, box jellyfish or other toxic creatures. The water is warm and clear and the currents are generally slow or non-existent.

Crown of Thorns Starfish
Crown of thorns starfish. Kona Coast. 25 ft depth. Photo credit: Clem Classen

The geology can be spectacular, with wondrous caves and beautiful drop-offs.

Manta Kona Coast Big Island Hawaii Horizon BnB
Clem with Manta. Kona Coast. 50 ft depth.

Deep water, pelagic sea creatures can be found relatively close to shore. These include manta rays, dolphins, and even giant whale sharks – don’t worry they’re not dangerous, they’re in fact a docile, plankton feeder. For more detail on the whale shark: https://oceanservice.noaa.gov/facts/bigfish.html

Tinker's butterfly Horizon Guest House Big Island
The rare tinker’s butterfly fish. Big Island. 135 ft depth. Photo credit: Clem Classen

And there’s always the famous humpback whale! You’re unlikely to encounter this mammal during a dive, but the spectacular displays topside, put on by the whales when they breach, is not to be missed if you happen to be on the island during ‘whale season’ (December to March).

Masked Butterfly Honaunau Big Island Horizon BnB

Where to dive?

Horizon Guest House is just minutes from one of the best local snorkeling spots – Two Step. We also have masks and snorkels on hand for guests to use.

Big Island Divers

But if you’re looking for a more comphrensive diving and/or snorkeling experience we recommend Big Island Divers. Corrine and the team will help you decide on what experience best suits you, whether it’s snorkeling, either with dolphins or as part of a whale watching trip, or one of the many scuba diving packages. Don’t forget their legendary Kona Manta Ray Night Dive – it’s not to be missed!

For more information on Big Island Divers check out their website www.bigislanddivers.com  and their amazing Instagram https://www.instagram.com/bigislanddivershawaii/

Experience diving here on the Big Island! Stay close to the action at Horizon Guest House. To book now click the button below.

Author: Angus Meek