FIGURES 142–153. Chaetoceros lauderi culture material, strain PMFL1. Figs 142–143, 151: LM. Figs 144–146, 148, 150: TEM. Figs 147, 149, 152–153: SEM. 142) Complete chain showing setae orientation. 143) Intercalary cells with numerous chloroplasts. 144) Two overlapped sibling valves showing valve ornamentation. 145) Detail of the valve with central annulus and anastomosing ribs. 146) Terminal valve with slit-like rimoportula (arrow). Note the parallel ribs on the valve mantle. 147) Terminal valve with external flattened tube of the rimoportula. Note the low hyaline rim on the marginal ridge. 148) Detail of the terminal valve with the slit-like rimoportula. 149) Detail of a seta. 150) Detail of the girdle band. 151) Resting spore. Note the single ring of puncta on the advalvar margin of the secondary valve mantle (arrow). 152) Primary valve of the resting spore. 153) Secondary valve of the resting spore with the single ring of puncta on the advalvar mantle margin. Scale bars: 142=50 μm; 143=20 μm; 151–153=10 μm; 144, 146–147=5 μm; 145, 148–150=1 μm.