Costasiella sp. 02  Genus: Pruvot-Fol, 1951
identified by Kathe Rose Jensen, thanks!
She writes: "I am almost certain it is a species of Costasiella - the alga looks very much like
Avrainvillea and the size and general shape of the animal are also about right. So even if eyes
are not visible, I'll venture an educated guess at Costasiella.
I will not even try to guess a species name though."
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