Pygmy Sweepers (Parapriacanthus ransonneti/Parapriacanthus guentheri) on the Wreck of the Ulysses, Egypt, Red Sea.
Photo copyright Tim Nicholson.
Taken on the Ulysses, Red Sea, Egypt.
Also known as glass fish and Red Sea Dwarf Sweepers, schools of these small fish are found not only in the Red Sea but elsewhere in the Indo-Pacific. They like shady places: wrecks, overhangs and caves. They feed at night on zooplankton.
Pygmy sweepers living in the Red Sea used to be known as Parapriacanthus guentheri, but it is now thought that there is just one species and Parapriacanthus guentheri is an obsolete name. They have light-emitting compounds in their guts, presumably gained from food they have eaten.
The Underwater Photographer: Digital and Traditional Techniques, by by Martin Edge, Paperback, 536 pages (2009)
Coral Reef Guide Red Sea, by Robert Myers and Ewald Lieske
Shipwrecks from the Egyptian Red Sea by Ned Middleton; Immel Publishing, 196 pages.