Light and electron microscopic description of Polysporoplasma n. g. (Myxosporea: Bivalvulida), Polysporoplasma sparis n. sp. from Sparus aurata (L.), and Polysporoplasma mugilis n. sp. from Liza aurata L. European Journal of Protistology, 31(1), March 15 1995: 77-89. 78 [Zoological Record Volume 132]