Genicanthus

Genicanthus is a genus of marine angelfishes in the family Pomacanthidae. Known commonly as swallowtail or lyretail angelfish, these fishes are so-named for the distinctive shape of their tailfins.

In aquaria

This genus of angelfishes, in comparison to the other species found in hobby aquaria, are a good choice for beginners as they do not get nearly as large as some of the others. Another unique attribute is that swallowtail angels will tolerate each other and can be kept in pairs or as a single male with a harem, though it is typically best to add them to a tank at the same time. If added on by one, the angel which is added first may become aggressively territorial towards any new additions. Unlike others in the family Pomocanthidae, the angelfish species in the genus Genicanthus are generally considered to be reef safe.
Also unlike most other members of the Pomacanthidae, those in Genicanthus are sexually dimorphic, meaning males and females are easily distinguishable. Fish in this species possess a small mouth relative to its size. This small mouth is well adapted for feeding on plankton in the water column. As planktivores, members of Genicanthus generally will not nip corals and sessile invertebrates.

Etymology

The name of this genus means “thorn cheek”, a reference to the spines on the rear margin of the operculum, a feature common to all angelfish.

Species

The following species are classified under the genus Genicanthus:

Male	Female	Scientific name	Common name	Distribution
		Genicanthus bellus Randall, 1975.	Ornate angelfish	western Pacific and eastern Indian Ocean
		Genicanthus caudovittatus .	Zebra angelfish	waters of Madagascar, the Maldives, Mauritius and Réunion and is also known in Weh Island
		Genicanthus lamarck .	Blackstriped angelfish, Lamarck's angelfish	tropical waters of the Indo-West Pacific
		Genicanthus melanospilos .	Spotbreast angelfish	Indo-Malayan region to the southwestern Pacific Ocean, and from the Ryukyu Islands to New Caledonia and Fiji.
		Genicanthus personatus Randall, 1975.	Masked angelfish	the Hawaiian Islands
		Genicanthus semicinctus .	Halfbanded angelfish	from Lord Howe Island, and the Kermadec Islands in the south-western Pacific Ocean
		Genicanthus semifasciatus	Japanese swallow	Western Pacific
		Genicanthus spinus Randall, 1975.	Pitcairn angelfish	Eastern Pacific: Cook Islands to Ducie Atoll
		Genicanthus takeuchii Pyle, 1997.	Spotted angelfish	Northwest Pacific: Marcus Island and the Ogasawara Islands
		Genicanthus watanabei .	Blackedged angelfish	West-central Pacific: Taiwan to the Tuamotu Islands, north to Ryukyu Island, south to New Caledonia and the Austral Islands; Marianas and Marshalls in Micronesia.