These stunning images of Haliclystus sanjuanensis were taken by Katherine Panfilova while she was snorkelling in an area off of West Sooke, British Columbia. Like most members of the order, Stauromedusae, H. sanjuanensis is quite small (4 cm max). They are a shallow dwelling creature and, consequently, one that snorkelers should have the opportunity to see often, but their sightings tend to be rare and the ability to get a good photo even more so.  Unlike most medusae, they are not free floating. Their sticky stalks remain fixed to the substrate to which they are attached. Their varying colours help them blend in well with their hosts (usually rocks, eelgrass and other shallow algaes/seaweeds). By using their pom-pom-tipped appendages to sweep at passing detritus, they draw food into their stomach much like some sea cucumbers and anemones do.  In fact at one point Stalked Jellies were thought to be members of the order Dendrochirotida and/or Actiniaria.  Little is really known about them. Haliclystus sanjuanensis is technically an undescribed species, what they call in the world of taxonomy a nomen nudum.   The Marine Detective, Jackie Hildering, has an excellent blog post on how difficult it can be to identify these animals.  And Claudia Mills et al explain the complexity of the species and nomenclature in their brilliant article on Cnidarians, pg 172.