Protists (unicellular eukaryotes) are important members of planktonic communities in marine ecosystems. Among them the Radiolaria, composed of four main taxa (Acantharea, Spumellaria, Nassellaria, and Collodaria) are amoeboid cells exhibiting mineral skeletons made essentially of silica or strontium sulfate. Siliceous radiolarians sinking down to the ocean's floor provides an invaluable fossil record extensively used for biostratigraphy and paleo-environmental reconstructions. Radiolaria are abundant and widespread in modern oceans but their diversity and evolution is poorly understood. In particular the links between their morphological and molecular taxonomy is lacking severely. They are active predators feeding on a large size spectrum of prey, which confers them a key role in marine food webs and in biogeochemical processes. Many radiolarian species dwelling in the surface layer of the oceans harbor micro-algae as intra cellular symbionts (photosymbiosis). As for their hosts, the identity of the symbionts remains unclear.
Renkañ is the word for organizing, ordering, in Breton language. The Renkañ application is used by the planktonic symbiosis research team at the Station Biologique de Roscoff to organize and share information on Radiolarians specimens available in the lab. Samples are composed mainly of single cells collected and isolated worldwide before to be processed in the lab. Information on collection procedures, location, morphology and molecular markers are provided for each specimen. Within this context a particular focus is given at organisms living in photosymbiosis so one can link host and symbionts related information. Access to unpublished data and internal lab organizational information are restricted