Anthias ventralis and Anthias hawaiiensis have been placed into the new genus Compsanthias by Dr. Anthony Gill. In a paper published in the journal Zootaxa, Gill erects the new genus based on differences in the infraorbital bones, anal fin ray counts, and the presence of a red to purple oblique stripe from behind the upper part of the eye to the upper part of the head.
Compsanthias is so named from the Greek for elegant or pretty and the above species have been placed in Anthias and Pseudanthias previously. The author states that the family Anthiadidae includes around 250 species but that the composition and generic classification of the family is problematic, although “improving”.
Until recently, around one-quarter of the species were placed in the “poorly diagnosed” genus Pseudanthias and although a third of them have been allocated to other genera a combination of characteristics preclude ventralis and hawaiiensis from other existing genera. Compsanthias ventralis becomes the type species.
Called the Longfin Anthias or Longfin Basslet, C.ventralis inhabits coral reefs in the Western Pacific with a depth range of 26 to 120 meters (85 to 394 ft) where they seek the shelter of caves and overhangs. They’re one of the most highly prized anthias species by reef keepers.
The Hawaiian Longfin Anthias, C.hawaiiensis, is as the name suggests a Hawaiian endemic and has been viewed as a subspecies of C.ventralis by some in the past. It inhabits caves and overhangs in even deeper reefs of 26–219 m (85–719 ft) in Hawaii and the Johnston Atoll.
More info
Compsanthias, new genus of Pacific Anthiadidae (Teleostei), https://doi.org/10.11646/zootaxa.5463.3.3