Fungi form several kinds of spores, and some are simply thickened, food storing cells found scattered within the ordinary hyphal threads rather than at special reproductive structures. Such a cell swells up, packs itself with reserve food, and develops an unusually thick wall compared to its neighbours, allowing it to survive harsh conditions. This resting, thick walled cell within the mycelium is called a chlamydospore, unlike ascospores, conidiospores or sporangiospores which form through more specific reproductive processes.