Auxospores typically play a role in growth processes, sexual reproduction or dormancy.
Consequently, each division cycle decreases the average size of diatom cells in a population.
[3] Finally, auxospores can be produced by diatoms to act as dormant stages, sometimes referred to as "resting spores."
[1] The auxospore is covered by a flexible cell wall called perizonium, which replace the thin zygotic membrane when the auxospore originates from a zygote, and doesn't restrict cell growth.
A few species don't form a perizonium, and has a wall of scales and imperforate silica instead.