What are these ??

[kanesaquatics]

I found this growing on my green star polyps. Need help

 

[ISpeakForTheSeas]

I found this growing on my green star polyps. Need help

Looks like it may be coral boring spionid worms:
https://www.reef2reef.com/threads/coral-boring-spionid-worms-an-ugly-bane-to-sps.929439/

 

[EeyoreIsMySpiritAnimal]

Looks like it may be coral boring spionid worms:
https://www.reef2reef.com/threads/coral-boring-spionid-worms-an-ugly-bane-to-sps.929439/

Can they bore into soft coral?

 

[ISpeakForTheSeas]

Can they bore into soft coral?

I honestly don’t know. I would imagine so, but I can’t find any studies to verify it (soft corals aren’t reef building, so they’re not likely to be studied in connection with bioeroders like coral boring worms) - that said, if these are boring Spionids, I’d guess they’re probably boring into the rock/frag plug underneath and just popping up through the coral rather than living in the coral itself.