INTRASPECIFIC VARIATIONS OF BIOLUMINESCENCE IN A POLYCHROMATIC POPULATION OF AMPHIPHOLIS-SQUAMATA (ECHINODERMATA, OPHIUROIDEA)

Six colour varieties were recognized in an intertidal population of Am phipholis squamata from Normandy (France). Each variety exhibits its o wn capacity to produce light, the light emitted by the most luminous v ariety being 500 times more intense than that emitted by the least lum inous one. Differences in luminescent capabilities observed between va rieties do not seem to be due to differences in pigmentation or to be of exogenous origin. It was shown that the capability to produce light changes according to whether individuals are brooding or not, broodin g individuals emitting a more intense light than non-brooding ones. Th is supports the defensive use of luminescence generally associated to ophiuroid production of light. However, Light capabilities differ so m uch between A. squamata colour varieties that bioluminescence could al so be associated with another role in the species.