What is "hemovanadin"

n. A pale-green pigment, similar to hemoglobin but containing vanadium instead of iron, found in the vanadocytes of sea squirts

Hemovanadin is used to refer to the pale green vanabin proteins found in the blood cells, called vanadocytes, of ascidians (sea squirts) and other organisms. It is one of the few known vanadium-containing proteins.

German chemist Martin Henze first detected vanadium in ascidians in 1911. Unlike hemocyanin and hemoglobin, hemovanadin is not an oxygen carrier.