. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. ALGAL PATHOGEN IN A GORGONIAN CORAL 379 AL V •'.. *—.. FIGURE 10. Association of coral amoebocyte and algal filaments. A. Light micrograph of amoebocytes aggregated near an algal filament; note PAS-positive vesicles; scale bar = 50 nm. B. Low power electron micrograph of amoebocyte lysing and releasing contents near two algal filaments; scale bar = 1 ^m. c. Mesoglea coating an algal filament; scale bar = 1 ^m. AL, algae; AM, amoebocyte; CW, cell wall; CY, chloroplast; M, mesoglea. latter authors give familial characters t
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. ALGAL PATHOGEN IN A GORGONIAN CORAL 379 AL V •'.. *—.. FIGURE 10. Association of coral amoebocyte and algal filaments. A. Light micrograph of amoebocytes aggregated near an algal filament; note PAS-positive vesicles; scale bar = 50 nm. B. Low power electron micrograph of amoebocyte lysing and releasing contents near two algal filaments; scale bar = 1 ^m. c. Mesoglea coating an algal filament; scale bar = 1 ^m. AL, algae; AM, amoebocyte; CW, cell wall; CY, chloroplast; M, mesoglea. latter authors give familial characters that agree with our material. These include branching, filamentous, chlorophytic microalgae that may form pseudoparenchy- matous masses with uninucleate cells containing parietal chloroplasts with one or more pyrenoids; colorless, nonseptate, anucleate setae may be present depending upon environmental conditions, especially nutrient depletion. Ultrastructural char- acteristics first described by Stewart el al. (1973) indicate that ulvellacean genera may also be distinguished by their lack of plasmodesmata and the presence of traversing thylakoid membranes in the pyrenoid. Our material agrees with this diagnosis (Fig. 2D, E, F) but is clearly different (segregative cell division) from the siphonaceous alga found in Gorgonia by Morse et al. (1977, 1981). The genus Entocladia has been circumscribed by O'Kelly and Yarish (1981). Our material conforms to their characteristics with the exception that the number of flagella appears more variable. Occurrence of tri- and pentaflagellate forms may be an artifact of culture and preparation. E. endozoica probably produces bi- and quad- riflagellate motile cells which are characteristic of this group (Yarish, 1975; Nielsen, 1979; O'Kelly and Yarish, 1980, 1981). The pigments of the genus Entocladia include chlorophylls a and b, carotenes, lutein, neoxanthin, siphonaxanthin, and violaxanthin (O'Kelly, 1982). The characters that distinguis
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
