#growth spore
- Auxospore — A specialized reproductive cell or growth spore formed as a result of sexual reproduction (or autogamy) in unicellular phytoplanktonic algae of the diatom class (Bacillariophyceae); this spore expands considerably in volume to restore the original size of the species, compensating for the progressive reduction of the siliceous frustule that occurs during successive asexual divisions.