| mesoproterozoic archaeoellipsoides: akinetes of heterocystous cyanobacteria. | the genus archaeoellipsoides horodyski & donaldson comprises large (up to 135 micrometers long) ellipsoidal and rod-shaped microfossils commonly found in silicified peritidal carbonates of mesoproterozoic age. based on morphometric and sedimentary comparisons with the akinetes of modern bloom-forming anabaena species, archaeoellipsoides is interpreted as the fossilized remains of akinetes produced by planktic heterocystous cyanobacteria. these fossils set a minimum date for the evolution of deri ... | 1995 | 11539549 |