MEDUSAE, SIPHONOPHORES AND CTENOPHORES OF THE ALBORAN-SEA, SOUTH WESTERN MEDITERRANEAN

Fifty-eight species of planktonic Cnidaria and Ctenophora were observe d and collected in the Alboran Sea (western Mediterranean) during a cr uise in April 1991 on the RV Seward Johnson. Eleven stations were samp led 10 to 21 nautical miles off the north coast of Morocco between the Strait of Gibraltar and the Cap de Trois Fourches: 26 dives using the manned submersible Johnson-Sea-Link I were made to bottom depths of 3 70-850 m, and at 5 of the same stations 7 blue water SCUBA, dives were made from the surface to about 15 m. Twelve species of hydroidomedusa e, 18 species of siphonophores, 6 species of scyphomedusae, and 22 spe cies of ctenophores were collected. The most numerous species seen fro m the submersible in deep water included Solmissus albescens, Haliscer a conica, Forskalia (?)formosa, Lensia conoidea, Abylopsis tetragona, Paraphyllina ransoni, Periphylla periphylla, Euplokamis stationis, Bat hocyroe fosteri, bolinopsis infundibulum, an undescribed cydippid cten ophore, and an undescribed lobate ctenophore. Species that were most n umerous near the surface were Pandea conica, Solmaris leucostyla, Nano mia bijuga, Haeckelia beehleri, Pleurobrachia rhodopis, Bolinopsis vit rea, Ocyropsis maculata immaculata, Beroe ovata, and an undescribed cy dippid ctenophore. Advantages of using a submersible for this study in cluded the ability to collect in perfect condition fragile forms like siphonophores and ctenophores that fall apart when collected in nets, the possibility of obtaining a realistic image of small-scale distribu tion throughout the water column, and to sample plankton close to the sea floor.