The Helicosporidium sp. ATCC 50920 genome sequence and gene models were not determined by the Joint Genome Institute (JGI), but were downloaded from NCBI on Oct 31, 2019. In order to ensure this genome is comparable to those sequenced by the JGI, we applied filters to remove if present: 1) transposable elements, 2) pseudogenes, 3) alternative transcripts and overlapping models, 4) alleles on secondary scaffolds and 5) unsupported short models. This resulted in the removal of 431 models and the generation of the FilteredModels2 (GeneCatalog) gene track. All published models are available in the ExternalModels track. Please note that this copy of the genome is not maintained by NCBI and is therefore not automatically updated. In order to allow comparative analyses with other algal genomes sequenced by the JGI, a copy of this genome is incorporated into PhycoCosm. The JGI Annotation Pipeline was used to add functional annotation to this genome.