A new species of the butterflyfish genus Prognathodes has been described from several specimens collected at depths of 180-200 feet (55-61 m) off Pearl and Hermes Atoll, Northwestern Hawaiian Islands.

The Pete Basabe’s butteflyfish (Prognathodes basabei) at a depth of 180 feet (55 m) off Pearl and Hermes Atoll, Northwestern Hawaiian Islands. Image credit: Greg McFall / NOAA.
“Butterflyfish are the glamour fish of the coral reefs,” said Dr. Richard Pyle of the Bishop Museum, one of the scientists who described the new species.
“They are colorful, beautiful, and have been very well-studied worldwide. Finding a new species of butterflyfish is a rare event.”
Dr. Pyle and his colleague, NOAA scientist Dr. Randall Kosaki, officially named the species Prognathodes basabei and gave it the common name Pete Basabe’s butteflyfish.
“We take great pleasure in naming this species basabei, in honor of Peter K. Basabe, long-time diver, aquarium fish collector and resident of Kona, Hawai‘i, both for his role in the collection of the first specimen of this new species in 1998, and more generally for his extensive contributions and assistance to many researchers in the ichthyological community,” the authors explained.
Prognathodes basabei was first observed in video taken from manned submersibles more than two decades ago, at depths as great as 600 feet (183 m).
At the time, Dr. Pyle and University of Hawaii marine biologist E.H. ‘Deetsie’ Chave recognized this as a potential new species. However, because of the extreme depths, it was many years before technical divers using advanced electronic closed-circuit rebreathers were able to collect and preserve specimens in a way that would allow proper scientific documentation.
“Discoveries such as this underscore how poorly explored and how little we know about our deep coral reefs. Virtually every deep dive we do takes place on a reef that no human being has ever seen,” Dr. Kosaki said.

A group of three Pete Basabe’s butteflyfish (Prognathodes basabei) at a depth of 295 feet (90 m) off Pearl and Hermes Atoll, Northwestern Hawaiian Islands. Image credit: R. L. Pyle.
Prognathodes basabei is a member of the genus Prognathodes, a group generally inhabiting deeper habitats than most other butterflyfish species.
In addition to this new species, Prognathodes includes seven valid species from the Atlantic, two from the tropical eastern Pacific, and two from the Indian Ocean and western Pacific.
Adult Prognathodes basabei normally measure between 3.5 and 4 inches (9-10 cm) in length.
It is yellow dorsally fading to white ventrally, sometimes entirely white, with three black bands and narrow white margins on each side of the body.
The species was observed or collected at depths of 148-614 feet (45–187 m) at several locations throughout the Hawaiian Archipelago, including both the main Hawaiian Islands (Hawai‘I, O‘ahu, Penguin Banks) and the Northwestern Hawaiian Islands.
“One particularly unusual characteristic of this species is the tendency for it to be found in groups of three individuals,” the scientists said.
“Another interesting aspect is the strikingly similar color pattern it shares with both the Palau species, and with P. guezei, in contrast to the deep genetic divergence that exists between the Hawaiian and Palauan specimens.”
Research describing the new species is published online in the journal ZooKeys.
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Pyle R.L. & Kosaki R.K. 2016. Prognathodes basabei, a new species of butterflyfish (Perciformes, Chaetodontidae) from the Hawaiian Archipelago. ZooKeys 614: 137-152; doi: 10.3897/zookeys.614.10200