Non-motile sperm cells

Non-motile sperm cells called spermatia lack flagella and therefore cannot swim. They are often confused with conidia. Conidia are spores that germinate independently of fertilization, whereas spermatia are gametes that cannot give rise to a new organism by themselves, but instead are required for fertilization. Spermatia are produced in a spermatangium.
Because spermatia cannot swim, they depend on their environment to carry them to the egg cell. Some red algae produce non-motile spermatia that are spread by water currents after their release. The spermatia of rust fungi are covered with a sticky substance. They are produced in flask-shaped structures containing nectar, which attract flies that transfer the spermatia to nearby hyphae for fertilization in a mechanism similar to insect pollination in flowering plants.