The Singapore or Vermiculated Angelfish (Chaetodontoplus mesoleucus) is a long time favorite in the hobby for its stunning coloration and inquisitive personality. They are relatively affordable, and commonplace these days. A much lesser known “variant” out of Palau has been identified for some time and collected infrequently. Our good friend John Coppolino saw one this [...]
The Singapore or Vermiculated Angelfish (Chaetodontoplus mesoleucus) is a long time favorite in the hobby for its stunning coloration and inquisitive personality. They are relatively affordable, and commonplace these days. A much lesser known “variant” out of Palau has been identified for some time and collected infrequently.
Our good friend John Coppolino saw one this past year while in Osaka, Japan (photo shown below). This fish has been imported to Japan before, but now thanks to the work of Luiz Rocha and Jack Randall this “variant” will be known as Chaetodontoplus poliourus where ever it happens to be seen.
Chaetodontoplus mesoleucus - a common, but colorful angelfish
The newly described “variant” Chaetodonplus poliourus – note the gray tail.
The markings are similar, no doubt, but through DNA testing Rocha and Randall have identified a new species and qualified the opinions that a few ichthyologists have had for some time. The easiest way to distinguish C. poliourus and C. mesoleucus is by their tail or caudal fin. C. poliourus exhibits a gray tail with a slight orange border. In contrast, C. mesoleucus sports a yellow caudal, with a clear edge.
Chaetodontoplus poliourus for sale in Japan as a variant, prior to the species description. Photo by John Coppolino.
The name of this new species was hinted at with the teaser phrase “gray tail” (J. Coppolino, Pers. comm.). In hindsight it makes sense, but I don’t think anyone would have guessed poliourus …. even thought it literally means gray tail! Polio is Latin for gray, while urous is Latin (or Greek depending on the spelling) for tail.
Special thanks to Luiz Rocha for his work in ichthyology and for sharing his beautiful photos of the new Chaetodontoplus poliourus with us. See the full study here:
