Diatom Collection

diatom photo

The California Academy of Sciences holds one of the largest diatom collections in the world with over 50,000 samples and 125,000 microscope slides.  At least 1,400 slides contain vouchers or types.

Diatom Collection Database (= Hanna Database)

The Specimen, Sample, and Publication tables of the database can be searched. The Specimen table contains detailed records of 75,000 specimens (taxa) that have been identified on slides. The Sample table contains detailed information on 34,000 samples accessioned in the Diatom Collection. The Publication table contains 12,000 bibliographic references.  We are gradually adding high resolution photomicrographs to the Specimen table.

The Types Catalogue provides information on types in the CAS Diatom Collection up to 1997. Post-1997 types are found in the Diatom Collection Database (Specimen table).

Diatom Identification Resources

Currently, the project focuses on recent freshwater diatoms of the United States. In the future, it will include marine and fossil taxa with an expanded geographic range.

Catalogue of Diatom Names

The Catalogue of Diatom Names is a searchable database that was assembled during the past 12 years and is regularly updated.  It includes all scientific names of diatom genera, species, and taxa at infraspecific ranks, with authorship, date, place of publication, page of description, basionym or replaced name (if applicable), status (valid or invalid), and occasionally type information.