Contribution Series Number 50: The New Lentin and Williams Index 2019

We are pleased to announce the publication of the 2019 edition of the “Lentin and Williams Index”. This dinoflagellate is the ninth complete revision of the 1973 original. That first edition was 176 small pages long, the 2017 Index was 1097 pages long, and the 2019 Index has grown to 1173 pages, with 338 new taxonomic entries and 73 new references.  As with the 2017 edition, the 2019 edition is intended as a digital publication and no printed copies will be made by the AASP Foundation … and is available free of charge. Just click here AASP Contribution Series No.50 and download it.  A companion new version of the DINOFLAJ (pronounced “dinofladge”) database, DINOFLAJ4, is also now available here:

The authors hope to continue to publish updates of the Index/DINOFLAJ every 2–3 years. So please continue to send new taxonomic papers to the corresponding author ( The same goes for any errors that you may see in either the 2019 Index or DINOFLAJ4.