Chrysochromulina throndsenii is a marine haptophyte alga named in honor of a Scandinavian researcher, reflecting the strong tradition of haptophyte taxonomy in Norwegian and Swedish phycological institutions. The species belongs to the family Prymnesiaceae and shares the characteristic features of the genus: a biflagellate cell body, a haptonema of variable length, and a surface coat of organic scales arranged in overlapping layers. Scale ultrastructure observed under electron microscopy provides the species-specific diagnostic characters essential for accurate identification within this morphologically conservative genus. C. throndsenii is documented from marine coastal waters, consistent with the broader distribution of Chrysochromulina species in temperate North Atlantic environments. As a photosynthetic nanoflagellate, it contributes to primary production and participates in the microbial loop as both a producer and potential mixotrophic consumer of bacteria. The significant role of haptophytes in the marine carbon and sulfur cycles underscores their ecological importance despite their microscopic size. The conservation status of C. throndsenii has not been evaluated by the IUCN, and the species is listed as Not Evaluated. Expanded molecular surveys will be necessary to fully understand its distribution and evolutionary relationships.