The light and electron microscopical examination of nanoplankton from the Andaman Sea has revealed the existence of a very rich choanoflagellate fauna in tropical waters. Approximately 45 loricate choanoflagellates (Acanthoecidae, Choanoflagellida) were recorded from samples collected Sept. 1980, in the vicinity of Phuket Island, Southwest Thailand. Among the undescribed taxa encountered were several which possessed a lorica composed of flattened costal strips exclusively. Six of these are described and allocated to STEPHANACANTHA gen. nov. and PLATYPLEURA gen. nov., typified by the Mediterranean species S. campaniformis (Leadbeater) comb. nov. (Parvicorbicula campaniformis) and P. infundibuliformis (Leadbeater) comb. nov. (Parvicorbicula infundibuliformis). Species of Stephanacantha (S. dichtotoma sp. nov., S. parvula sp. nov. and S. formosa sp. nov.), are characterized by very conspicuous bifurcations of the longitudinal costae and by the presence of an upright spine at 1 end of each anterior transverse costal strip. Species of Platypleura (P. cercophora sp. nov., P. acuta sp. nov. and P. perforata sp. nov.) are characterized by a very regular arrangement of transverse costae (2-3) and longitudinal costae which attach the transverse costae, at the joints of adjacent transverse costal strips.
|Publication status||Published - 1983|