Light and electron microscope observations onNephroselmis gaoae sp. nov. (Prasinophyceae)

Nephroselmis gaoae sp. nov. is described on the basis of light and electron microscope observations of cultured material originally collected and isolated from seawater of Jiaozhou Bay, Qingdao, China. The periplasts on the cell body and flagella are covered by five types of scales, two types on the flagella and three on the body. Among these, the morphology and the number of spines of large stellate body scales differ remarkably from those of previously described species ofNephroselmis. Apart from these, the unusual fine structure of the eyespot (stigma) is very characteristic. As in the other species ofNephroselmis, the eyespot lies immediately under the two-membraned chloroplast envelope; unlike the others, however, it is not composed of a number of osmiophilic globules, but consists of about 14 curved rod-shaped osmiophilic bodies arranged loosely and randomly. This feature distinguishes the present new species not only from the other species ofNephroselmis but also from the other motile algal species, the eyespots structure of which had been previously described. Contribution No. 2316 from the Institute of Oceanology, Chinese Academy of Sciences. This paper was presented at the XIVth International Seaweed Symposium held in Brittany, France, 1992.