Malachite green metabolized into LMG. Only the cation MG is deeply colored, whereas the leuco and alcohol derivatives are not. This difference arises because only the cationic form has extended pi-delocalization, which allows the molecule to absorb visible light. The leuco form of malachite green was first prepared by Hermann Fischer in 1877 by condensing benzaldehyde and dimethylaniline in the molecular ratio 1:2 in the presence of sulfuric acid. Malachite green is traditionally used as a dye. Kilotonnes of MG and related triarylmethane dyes are produced annually for this purpose. MG is active against the oomycete "Saprolegnia", which infects fish eggs in
Malachite kingfisher A molecular phylogenetic study published in 2007 confirmed that the most closely related species is the Malagasy kingfisher, ("Corythornis vintsioides"). The Malagasy kingfisher has a black bill and greenish crest, and is not quite as dependent on water as the African species. It is otherwise similar in plumage and behaviour to the more widespread malachite kingfisher. The São Tomé kingfisher and the Príncipe kingfisher were sometimes considered as distinct species but a study published in 2008 showed that they are both subspecies of the malachite kingfisher. There are five subspecies: This is a small kingfisher, around in length. In Southern