FIGURES 5–7 in Reorganizing parasitic Delesseriaceae: taxonomic revision of Asterocolax

FIGURES 5–7: Phycodrys denticulatus FIGURE 5: Mature parasitic pustule of Phycodrys denticulatus on its host Phycodrys fimbriata. Thallus is yellow in color with several round branches. Scale bar = 1 mm. FIGURE 6: 5 µm cross section of plastic embedded Phycodrys denticulatus stained in aniline blue. Tetraspores (*) occur along the branches of Phycodrys denticulatus and divide tetrahedrally or obliquely cruciate. Tetraspores average 40 x 60 µm. Scale bar = 100 µm. FIGURE 7: 5 µm cross section of Phycodrys denticulatus infecting Phycodrys fimbriata stained in aniline blue. Given the parasites immediate infection of host cells, it is near impossible to differentiate parasite cells from infected host cells. The medullary cells in the parasite thallus and the likely infected cells underlying the developing parasite thallus are conspicuously larger than uninfected host cells and filled with floridean starch granules. The cell walls of these extremely large medullary cells are also thicker than uninfected cells, a probable response to infection. Scale bar = 100 µm.