Tunicate/Sponge or something else?

[swiss1939]

Large mass of white tubes coming out of a central spot on the underside of a rock got from TBS. Started small and has grown pretty large and wide over 6 months. Now the tubes are showing up on other rocks near it.

They don't move or sway.

 

[logibear]

That’s very interesting. Following along. My guess would be tunicate but I’ve never seen any like that

 

[swiss1939]

Started out about a quarter sizes. Now it's between golf ball and baseball sized.

 

[logibear]

@LiverockRocks is the ultimate source

 

[Maho.B]

Tube sponge maybe?

 

[LiverockRocks]

Wowie that is interesting! Forwarded your image to J to learn her thoughts. Thank you for sharing!

 

[LiverockRocks]

Large mass of white tubes coming out of a central spot on the underside of a rock got from TBS. Started small and has grown pretty large and wide over 6 months. Now the tubes are showing up on other rocks near it.

They don't move or sway.

J - "My guess would be a tunicate; however, I cannot see an excurrent opening. I have not seen a similar organism on rock harvested from our farm."

 

[swiss1939]

Interesting. I'll have to pull it out and get a better picture. It's definitely spread to another rock now.