Recently at Half Moon Bay on the Arabian Gulf coast, near Al Khobar, I saw a small number of Blubber Jellyfish (also known as Blue Blubber Jellyfish) Catostylus cf mosaicus. Half Moon Bay is a shallow and warm coastal area with the jellyfish having a translucent sub-hemispherical bell up to 35 centimetres across and eight conical arms without clubs or filamanets. They are quite common in the shallow coastal waters of Half Moon Bay, Dhahran and along the coast southwards to Abu Dhabi (United Arab Emirates) at certain times of the year, mainly the spring and summer. During the day the Blubber Jellyfish swims close to the water surface to obtain sunlight which it converts to energy. They come in various colours from translucent greyish white, like the ones at Half Moon Bay, to blue-green or even bright blue and reddish.
