Deskarati just received a wonderful comment from Phil Krause regarding the post we put on yesterday about Nummulites. In it Phil asks if anyone knows of a single cell organism larger than the Xenophyophores or the green algae called Caulerpa. So we had a good search around but couldn’t find anything larger. But on our travels we did notice this excellent picture of Sailors Eyeballs that we thought you might like. Thanks for the great comment Phil. – Deskarati
Valonia ventricosa, also known as “bubble algae” and “sailors’ eyeballs”, is a species of algae found in oceans throughout the world in tropical and subtropical regions. It is one of the largest single-cell organisms.
Valonia ventricosa typically grow individually, but in rare cases they can grow in groups, and they appear in tidal zones of tropical and subtropical areas, like the Caribbean, north through Florida, south to Brazil, and in the Indo-Pacific. Overall, they inhabit virtually every ocean throughout the world, often living in coral rubble. The farthest depth for viability has been seen as approximately 80 metres (260 ft).
The single-cell organism has forms ranging from spherical to ovoid, and the color varies from grass green to dark green, although in water they may appear to be silver, teal, or even blackish. This is determined by the quantity of chloroplasts of the specimen. The surface of the cell shines like glass. The thallus consists of a thin-walled, tough, multinucleic cell with a diameter that ranges typically from 1 to 4 centimetres (0.39 to 1.6 in) although it may achieve a diameter of up to 5.1 centimetres (2.0 in) in rarer cases. The “bubble” alga is attached by rhizoids to the substrate fibers.
Reproduction occurs by segregative cell division, where the multinucleic mother cell makes daughter cells, and individual rhizoids form new bubbles, which become separate from the mother cell.
Valonia ventricosa has been studied for its many interesting properties, such as the fact that the pores of V. ventricosa are absent of water. A study was conducted that showed that the properties of permeability in both osmosis and diffusion were identical. In studying the cellulose lattice, and its orientation in biological structures, Valonia ventricosa has undergone extensive X-ray analytical procedures. It has also been studied for its electrical properties, due to its unusually high electrical potential relative to the seawater that surrounds it. Via Valonia ventricosa