Observations on the basket star astroboa nuda (lyman) on coral reefs at elat (gulf of aqaba)

The authors carried out night observations on the population of the basket star Astroboanuda, on the coral reefs of Elat. Data are given on the distribution and density of population; their positions on the reef; their behaviour and reaction to strong illumination; and their mode of capturing of planktonic organisms. The stomach contents of a number of specimens were examined and the dimensions of the different food organisms were compared with the planktonic organisms collected simultaneously with a fine net. It was found that the animals keep regular night activity positions, and during daylight hide in nearby shelters. The time of emergence from, and return to the hiding places is specified. It is suggested that A. nuda might be found in abundance also on other coral reefs in the Red Sea and in the Indian Ocean.