Fig. 1

Structure of Actinotaenium cf. silvae-nigrae (strain CCAC 0140) and cell wall perforations produced by Orciraptor agilis. A Morphology of live Actinotaenium cells, DIC. B Surface of intact Actinotaenium cell with longitudinal rows of rosette-like ornamentations, SEM. C Detail of rosettes on the surface of Actinotaenium, SEM. D Orciraptor attacking a dead Actinotaenium cell, DIC. E Empty Actinotaenium cell with perforation and attached cell wall disc excised by Orciraptor, DIC. F Empty and perforated Actinotaenium cells that remained in an Orciraptor culture, SEM. G Detail of a perforation produced by Orciraptor with degraded rosettes (revealing cell wall pores) and eroded cellulose microfibrils, SEM. H Magnified erosion zone of G. Scale bars in A, D, E, F = 10 μm, in B = 2 μm, in C, H = 200 nm, in G = 1 μm