I would always be a bit cautious with GenBank taxonomy. This link does go to a Margaritella sp., which is what the author said it was but you never really know when you consider the number of errors in the database if it is correct or even if it is still in that genus.
This is actually Iphiteon panicea Bowerbank, 1869, a glass sponge (Porifera: Hexactinellida) that was formerly known as Margaritella coeloptychioides Schmidt, 1880. See the paper by Adams et al (1999) (attached).