World Register of Marine Species
The content of the registry is edited and maintained by scientific specialists on each group of organism. These taxonomists control the quality of the information, which is gathered from the primary scientific literature as well as from some external regional and taxon-specific databases. WoRMS maintains valid names of all marine organisms, but also provides information on synonyms and invalid names. It is an ongoing task to maintain the registry, since new species are constantly being discovered and described by scientists; in addition, the nomenclature and taxonomy of existing species is often corrected or changed as new research is constantly being published.
Subsets of WoRMS content are made available, and can have separate badging and their own home/launch pages, as "subregisters", such as the World List of Marine Acanthocephala, World List of Actiniaria, World Amphipoda Database, and so on. As of December 2018 there were 60 such taxonomic subregisters, including a number presently under construction.  A second category of subregisters comprises regional species databases such as the African Register of Marine Species, Belgian Register of Marine Species, etc., while a third comprises thematic subsets such as the World Register of Deep-Sea species (WoRDSS), World Register of Introduced Marine Species (WRiMS), etc. In all of these cases, the base data are entered and held once only as part of the WoRMS data system for ease of maintenance and data consistency, and are redisplayed as needed in the context of the relevant subregister or subregisters to which they may also belong.
Certain subregisters expand content beyond the original "marine" concept of WoRMS by including freshwater or terrestrial taxa for completeness in their designated area of interest; such records can be excluded from a standard search of WoRMS by selecting appropriate options in the online search interface.
WoRMS was founded in 2008 and grew out of the European Register of Marine Species and the UNESCO-IOC Register of Marine Organisms (URMO), which was compiled by Jacob van der Land (and several colleagues) at the National Museum of Natural History, Leiden  It is primarily funded by the European Union and hosted by the Flanders Marine Institute (VLIZ) in Ostend, Belgium. WoRMS has established formal agreements with several other biodiversity projects, including the Global Biodiversity Information Facility and the Encyclopedia of Life. In 2008, WoRMS stated that it hoped to have an up-to-date record of all marine species completed by 2010, the year in which the Census of Marine Life was completed. 
As of February 2018, WoRMS contained listings for 480,931 marine species names (including synonyms) of which 240,633 are valid marine species (95 % checked). Their goal is to have a listing for each of the approximately more than 240,000 marine species.  
- Catalog of Fishes
- Census of Marine Life (CoML)
- Ocean Biogeographic Information System (OBIS)
- "Towards a World Register of Marine Species". World Register of Marine Species. Retrieved 2009-02-16.
- "WoRMS - World Register of Marine Species". www.marinespecies.org.
- "About". World Register of Marine Species. Retrieved August 24, 2013.
- Catherine Brahic (2008-06-25). "How many species live in the sea?". New Scientist.
- "WoRMS - World Register of Marine Species". World Register of Marine Species. Retrieved 2018-02-11.
- Costello, MJ; Bouchet, P; Boxshall, GW; Fauchald, K; Gordon, DP; et, al. (2013). "Global coordination and standardisation in marine biodiversity through the World Register of Marine Species (WoRMS) and related databases". PLOS ONE. 8 (1): e51629. doi: 10.1371/journal.pone.0051629. PMC 3541386. PMID 23505408.
- "Interim Register of Marine and Nonmarine Genera (IRMNG)". Lifewatch regional portal. LifeWatch. Retrieved 10 December 2018.
Wikidata has the property:
- Official website
- Horton, Tammy; Gofas, Serge; Kroh, Andreas; Poore, Gary C. B.; Read, Geoffrey; Rosenberg, Gary; Stöhr, Sabine; Bailly, Nicolas; Boury-Esnault, Nicole (2017-12-28). "Improving nomenclatural consistency: a decade of experience in the World Register of Marine Species". European Journal of Taxonomy. 0 (389). doi: 10.5852/ejt.2017.389. ISSN 2118-9773.
- Vandepitte, Leen; Vanhoorne, Bart; Decock, Wim; Vranken, Sofie; Lanssens, Thomas; Dekeyzer, Stefanie; Verfaille, Kevin; Horton, Tammy; Kroh, Andreas (2018-04-06). "A decade of the World Register of Marine Species – General insights and experiences from the Data Management Team: Where are we, what have we learned and how can we continue?". PLOS ONE. 13 (4): e0194599. doi: 10.1371/journal.pone.0194599. ISSN 1932-6203. PMC 5889062. PMID 29624577.