Aegina rosea is a species of hydrozoan of the family Aeginidae.

It is one of two species in the genus Aegina, which was believed to be monotypic, until molecular phylogenetic analysis revealed that Aegina rosea was a second species.

The tentacles have nematocysts and are capable of clasping.

It was originally found in the Pacific Northwest and has since been found in the Central Pacific Basin.

[2] Its maximum size is believed to be at least 32 millimeters in diameter.