Luminescent systems in apogonid fishes from the Philippines.

Luminescence has been discovered in five apogonid fishes from the Philippine Islands. The luminescent organ systems, which are of two types, are morphologically different from the systems in the Japanese cardinal fish, Apogon ellioti, and in the apogonid genus Siphamia. Extracts of the organs all show a luciferin-luciferase type of reaction and cross-react with extracts of Apogon ellioti, Parapriacanthus ransonneti, and Cypridina hilgendorfii.