Description
Strongly flattened cells with 2 flagella arising subapically from a depression in 1 of the flat sides. Cells oval or rounded when seen from the flat sides. From the narrow sides concave-convex. The flagella emerge from the convex side. Chloroplast a curved plate , covering most of the cell periphery . One species with 2 pyrenoids, the other without pyrenoids. Eyespot near the middle of the concave side. A system of contractile vacuoles near the flagellar bases. Cells covered with several types of scales , the largest visible in the light microscope, giving the ce II a punctate appearance . Two known species , both from fresh water. (right) . x1500 . (From Manton and Ettl , 1965) . Mesostigma viride Lauterborn 1894 (Figs . 9-11). Cells 15-18 ~m long, 11-13 ~m wide , and 5-7 ).lm thick. Cells covered with scales of 3 types : small subrhomboid maple-like underlayer scales , usually confined to the upper cell surface, several intermediate layers of naviculoid scales , and an outer layer of larger basket-like ones. The flagella 1260 PRASINOPHYCEAE covered with the rhomboid type arranged in a single layer. Known from fresh water in Europe and North America . showing chloroplast swollen with starch at periphery and very flat in center, the two flagella in longitudinal section inserted in the conical pit, contractile vacuole (CV), and scale layers on body and flagella. x5000. (From Manton and Ettl, 1965) body. Shadowcast, electron micrograph . x25,000. (Manton and Ettl, 1965).
Type species
Figures
Raw text
Strongly flattened cells with 2 flagella arising subapically from a depression in 1 of the flat sides. Cells oval or rounded when seen from the flat sides. From the narrow sides concave-convex. The flagella emerge from the convex side. Chloroplast a curved plate , covering most of the cell periphery . One species with 2 pyrenoids, the other without pyrenoids. Eyespot near the middle of the concave side. A system of contractile vacuoles near the flagellar bases. Cells covered with several types of scales , the largest visible in the light microscope, giving the ce II a punctate appearance . Two known species , both from fresh water. (right) . x1500 . (From Manton and Ettl , 1965) . Mesostigma viride Lauterborn 1894 (Figs . 9-11). Cells 15-18 ~m long, 11-13 ~m wide , and 5-7 ).lm thick. Cells covered with scales of 3 types : small subrhomboid maple-like underlayer scales , usually confined to the upper cell surface, several intermediate layers of naviculoid scales , and an outer layer of larger basket-like ones. The flagella 1260 PRASINOPHYCEAE covered with the rhomboid type arranged in a single layer. Known from fresh water in Europe and North America . showing chloroplast swollen with starch at periphery and very flat in center, the two flagella in longitudinal section inserted in the conical pit, contractile vacuole (CV), and scale layers on body and flagella. x5000. (From Manton and Ettl, 1965) body. Shadowcast, electron micrograph . x25,000. (Manton and Ettl, 1965).