If you dont mind me waxing eloquent over those corals, I sorta did my thesis on them and I love talking about them. Yeah, so they come from this planet in the astra 25195 system. The Astra Auroralis seeder ship came through and marked this dwarf gas planet's moon as a point of interest.

Huge metal content on the moon, when some follow up ships came by to check it out. Pretty standard surveying went on. Meteorological data on the gas planet came up anomalous, floating structures on the cloud decks. Man people were super excited for civs, but nah, just an unusual biosphere.