Turriplaca multicosta (Thomsen, 1978) Nicholls, 2012
basionym Pinaciophora multicosta Thomsen (1978)
(synonym Rabdiophrys multicosta Roijackers and Siemensma, 1988)
Diagnosis: Scales of two kinds. Protoplast unknown. Plate-scales circular, c. 1.5-2.0 µm in diameter, with a broad pattern-less rim. More heavily silicified towards the center of the scale. A less silicified central area is delimited by a circle of small perforations. A number of tiny circular structures (dark in the micrographs) are distributed over the central scale area. Spine-scales 2.5-6.0 µm long and c. 0.8 µm wide at the base. The spine-scale is composed of a long shaft (c. 0.1 µm in diameter) which is distally flattened into a conspicuous bifurcation, proximally abruptly widened into a circular basal plate. A number of curved costae interconnect the two branches of each bifurcation.
Type location: Marine, Dybso Fjord (Denmark). Surface water sample.