“What in the alien invasion is this?” questioned one aghast poster, while another joked that they were “Godzilla eggs.”

“All I can imagine is if I touched it or it touched me while in the water. I would freak out,” declared a third.

As it turns out, these slimy spheres are actually native aquatic microorganisms known as bryozoans.

Colloquially called “moss animals,” these microscopic filter feeders form colonies by building coral-like exoskeletons, which are found attached to submerged rocks, branches and other structures.

This carapace is comprised of a substance called chitin, which hardens when dry to “preserve the organism until rehydrated” like a sentient freeze-dried meal.

Don’t be alarmed by their Martian-like countenance — these critters “are of no danger to you or wildlife,” the ODWC explained.

In fact, bryozoans are conversely an “indicator of good environmental quality and clear water,” per the post.

“These animals are an important part of the ecosystem because they help clean the water and serve as prey for mussels, snails and even small fish,” the nature agency wrote. “They often spread through water connectivity or even by passing through the intestinal tract of fish or birds!”