ABSTRACT
Bioluminescence has been studied in four brittlestars, two from deep water and two from shallow. The two deepsea species were the ophiacanthid Ophiacantha abyssicola and an amphiurid Amphiura grandisquama, while the shallow water forms were the amphiurid, A. filiformis and an phiocomid Ophiopsila riisei. These represent four of the five brittlestar families in which luminescence is known, the fifth being the Ophioneridae. Field and laboratory observations showed two contrasting patterns of luminescence. In A. filiformis, the luminescence is confined to the arm spines, as it is in the closely related species Acrocnida brachiata. In the other species the luminescence is a property of the arms. In Amphiura filiformis, the light emission appears to be the function of basophilic gland cells in the spines which contain densely staining spherical granular bodies.
