In addition to Agalma elegans, there are 2 other species in the genus Agalma:
- Agalma okeni
- Agalma clausi
Distinguishing these close relatives:
Upper view of an Agalma elegans bract.
A. elegans has a flexible body and the bracts are soft and not prismatic.
- both the other species have stiff stems
- Agalma okeni:
- is shorter than A. elegans
- has prismatic bells and bracts
- prefers warmer waters and is not found around the UK
- Agalma clausi:
- has prominent red pigment spots on the bracts, prismatic bells and an involucrum which encloses both the cnidoband and terminal filaments (plus ampulla)
- is a much less common species, so far collected only in the Mediterranean, the Gulf of Maine and at 1 location in the tropical western Atlantic