Using flow cytometric analysis of fluorescence, we measured the genome sizes of 18 cultured ‘‘freeliving’’ species and 29 Symbiodinium spp. isolates cultured from stony corals, gorgonians, anemones, jellyfish, and giant clams. Genome size directly correlated with cell size, as documented previously for most eukaryotic cell lines. Among the smallest of dinoflagellates, Symbiodinium spp. (6–15mm)...

Most algae regularly experience periods of darkness ranging from a few hours to a few days. During this time, they are unable to photosynthesize, and so must consume stored energy products. However, some organisms such as polar algae and some microalgal cysts and spores are exposed to darkness for months to years, and these must use alternative strategies to survive. Some taxa, such as dinoflag...

Sporadic algal bloom development within a 10 year monitoring program in Virginia tidal tributaries of Chesapeake Bay is reviewed. These blooms were common events, characteristically producing a color signature to the surface water, typically short lived, occurring mainly from spring into autumn throughout different salinity regions of these rivers, and were produced primarily by dinoflagellates...

The discovery of a Hematodinium-like dinoflagellate infecting Nephrops norvegicus has led to a pathological investigation into the effects on the host and the apparent progression of the disease syndrome The parasite is systemic, invading the haemocoel and the connective tissues of most organs via the haemal spaces. An increase in the combined number of parasites and haemocytes in the haemolymp...

Sea-surface discolorations due to high concentrations of phytoplankton are called red tides. Their ecological significance is a long standing puzzle, and they are sometimes considered pathological. Here we propose that many red tides, particularly but not exclusively those comprised of certain autotrophic dinoflagellates, are presexual/sexual swarms, essential links in their complex life cycles...

Dinoflagellates are an economically and ecologically important eukaryotic algal group. The organization of their chloroplast genome appears to be radically different from that in plants and other algae. The gene content has been dramatically reduced in dinoflagellates, with the large-scale transfer of genes to the nucleus. Most of the remaining genes encode subunits of Photosystems I and II, th...

Coral reefs are one of the most important marine ecosystems, providing habitat for approximately a quarter of all marine organisms. Within the foundation of this ecosystem, reef-building corals form mutualistic symbioses with unicellular photosynthetic dinoflagellates of the genus Symbiodinium. Exposure to UV radiation (UVR) (280 to 400 nm) especially when combined with thermal stress has been ...