Figs. 1-6. . Prorocentrum maculosum sp. nov. Fig.1. Appearance of the right valve, including the periflagellar area. The valve surface is rugose with scattered poroids and the centre of the valve is devoid of poroids. The cell margin is surrounded by a row of marginal pores. Fig.2. In left valve view. The anterior end is flat to slightly concave and the centre of this valve is devoid of pores. Fig.3. Unevenly distributed kidney-shaped to circular or oblong valve pores are present on the valves. Fig.4. Distinct ridge appears as a flange around the cell, with a row of equally spaced marginal pores. Fig.5. The periflagellar area, set in a V-shaped depression, is a broad triangle with a raised margin. Flagellar pore (F) and auxiliary pore (A) are about equal in size and are surrounded by a curved and flared apical collar. Fig.6. The apparently protuberant apical collar viewed from the side.
EMu: Holotype SEM negative # 40012; SEM stub #140; Field # 66-87; Accession # 407159; Catalog # 60; Figure # 1.
Plate 44. Prorocentrum maculosum. Figs. 1-4. SEM. Fig. 1. Right valve: cell broadly ovate, narrowing apically. Valve surface rugose with scattered poroids; valve center devoid of poroids. Marginal pores evenly spaced (arrows). Fig. 2. Left valve: anterior end flat to slightly concave with raised apical ridge (arrows). Valve margins appear as a flange around cell. Fig. 3. Valve poroids: unevenly distributed on valve surface; circular to oblong or kidney-shaped. Fig. 4. Periflagellar area: broad V-shaped depression on right valve. Apical ridge (raised margin) on left valve. Flagellar (f) and auxiliary (a) pores surrounded by protuberant periflagellar collar (arrowheads); equal in size. Fig. 5. LM. Right valve: central pyrenoid (P) and large posterior nucleus (N) (M.A. Faust). Fig. 6. Line drawing: valve poroid and marginal pore arrangement (Figs. 1-4,6 after Faust 1993b)