Welcome to the flasher wrasse world.
I start this column with a short explanation of the genus Paracheilinus.
The genus is closely related to the genus Cirrhilabrus and shares it with coloration, behavior, and distribution, etc. The genus ranges the Red Sea, African coasts, islands of the Indian Ocean through Southeast Asia, north to southern Japan, the Marshalls, south to the Great Barrier Reef, Vanuatu, Fiji to samoa. They do not occur in the Hawaiian Islands or Cook Islands.
They are small reaching 10 cm or a bit larger and their basic color is orange to reddish yellow, often with long filaments on dorsal fin, but pelvic fins are short in any species.
They form a harem, comprising a dominant male, several females and juveniles, that is aggregating on the reef. They are feeding on small planctons but in home aquaria they will accept almost all the foods offered.
Like its relative, males have an ability of changing colors within seconds, red to blue, white or yellow partially.
At present the genus includes 14 valid species, and most of them were recently described. As some of them sometimes mix in their natural environment hybridized specimens will be reproduced on occasion. Then there are some cases that cannot be readily identified but we can find characters for both parents by close observation.
How to identify them? They are very similar at first glance, but there should be some distinct features in any species. You should pay attention to its caudal-fin shape, filaments on dorsal fin, anal-fin coloration, etc.
Well let's start the first member Paracheilinus cyaneus today.
The photo shows 4 Blue Flasher Wrasses (deeply lunate tail), and a Linespot Flasher (ronded tail, lower right), and two Cirrhilabrus. The species came from Sulawesi, but shipment was rather rare. Only recently the species found their trade into various countires and they will appear at retailers so often at present. How do they change colors ?
