You have a species of Thecaphora
Native species only. There are numeruos species, one of the most common is Obelia geniculata.It is a typical Thecaphora where the cup is clearly visible.
Drawing of Obelia geniculata (from Boullion et al. 2004)
You may use data, pictures,information etc. available ad the site, as long as you refere to the sourse.
The database as a whole is to be cited as follows:
NOBANIS. Available from http://www.NOBANIS.org. Data of access x/x/201x