We present a general overview of features and technical specifications of an original interactive key web application for the identification of species originally classified as Chrysochromulina. The list of originally described species belonging in the genus Chrysochromulina, is given and recent taxonomic changes in species and genera of the order Prymnesiales are provided. We briefly discuss the interest of such a key for the identification of phytoplanktonic species. (See Chrétiennot-Dinet MJ, Desreumaux N, Vignes-Lebbe R (2014) An interactive key to the Chrysochromulina species (Haptophyta) described in the literature. PhytoKeys 34: 47-60. doi: 10.3897/phytokeys.34.6242).

The genus Chrysochromulina is characterized by the presence of an unusual appendage, named "haptonema", long and coiling, inserted between two flagella, and a covering made of one to several layers of organic scales showing a specific pattern. Electron microscopy provided detailed information on morphological features and is necessary to identify these tiny species, often below 10 µm in size.

The combination of different criteria such as habitat, shape, size, length of haptonema and flagella, scale organization and pattern are used to differentiate the species. About sixty species of Chrysochromulina have been described in the literature, but recent investigations show that the genus is polyphyletic and new genera have been introduced, but pending information is needed for species that have not been gene sequenced.

Cell "in toto"
Cell "in toto" (SEM) © Chrétiennot-Dinet Marie-Josèphe
Cell covering (SEM)
Cell covering (SEM) © Chrétiennot-Dinet Marie-Josèphe
organic  scales with spines (SEM)
Organic scales with spines (SEM) © Chrétiennot-Dinet Marie-Josèphe

For any question regarding copyright permission on the illustrations used in our interactive key, please send an email to collections_patrimoniales@obs-banyuls.fr