STUDIES ON THE REPRODUCTION AND DISTRIBUTION OF ASTERINA BURTONI GRAY AND A. WEGA PERRIER (ASTEROIDEA) IN THE RED SEA AND THE EASTERN MEDITERRANEAN

ABSTRACT

An Indo-Pacific sea star considered to be Asterina burtoni Gray 1840, has penetrated into the Mediterranean Sea through the Suez Canal. This sea star is found in the Red Sea in two morphological forms, the pluriradiate and pentaradiate, the former of which reached the Mediterranean. Size differences in the two forms found in Elat Bay were studied. The histological structure of the gonads was examined as well, and the assumption made that a parasitic ascothoracic Crustacea causes the degeneration of the gonads in pentaradiate specimens. The distribution of the two forms is considered. It is concluded that the two forms are two separate species: Asterina burtoni Gray 1840, being the pentaradiate form and Asterina wega Perrier 1869, the pluriradiate form.