Traits influence dinoflagellate C:N:P

Dinoflagellates are amongst the most abundant and diverse groups of plankton in surface waters and contribute to food web productivity and C:N:P biogeochemistry. Here we analyse the C:N:P of marine, autotrophic, planktonic dinoflagellates compiled from culture data from the scientific literature and test if dinoflagellate C:N:P differs from the Redfield ratio, and whether variability in C:N:P is associated with three traits: cell size, wall structure and toxin production. We find the average C:N:P of dinoflagellates is 90:12:1; higher in C:N, and lower in C:P and N:P than the canonical Redfield ratio. In aggregate the three traits examined here account for between 20–31% while taxonomic order accounts for between 37–38% of the variance in C:N:P. Smaller-sized and thecate taxa are higher in C:N, C:P and N:P than larger-size and athecate taxa. Species known to be able to produce C-rich toxins tend to be higher in C:P and N:P while species known to be able to produce N-rich toxins are lower in C:N, C:P and N:P relative to non-toxic species. These results indicate that any average estimate of dinoflagellate C:N:P will be influenced by the relative number of taxa with these traits.