These include a centrosome with two concentric granular shells and axopodia much simpler in structure than in visually similar protists (other 'heliozoa').

[1] The genus Microheliella was described from an organism discovered contaminating a culture of the amoeba Cochliopodium from the Ebro Delta, Spain, collected in 2003 by Alexey Smirnov.

This organism was subsequently transferred into a pure culture through serial dilution and maintained at Oxford for nine years in a growth medium of 50% artificial seawater, with naturally occurring bacteria as its food.

Combining the newly obtained morphological and genetic data, it was formally described by Thomas Cavalier-Smith and Ema E. Chao in 2012 as the novel species Microheliella maris.

[1] To accommodate this genus, the monotypic family Microheliellidae and order Microhelida were created, and classified as part of the phylum Cryptista in accordance to phylogenetic analyses.