Scyphozoans have diverse symbiotic associations, including mutualism, commensalism, and parasitism. Peachia is one of the few parasitic sea anemones that can kill several species of hydromedusae and cause the demise of their host population. In Australia, the young stages of these burrowing sea anemones have been observed parasitizing jellyfish from the genus Cyanea but there are no records of Peachia parasitizing the genus Chrysaora.
Twenty-five adult Chrysaora kynthia medusae were collected from the Gold Coast Seaway during summer and were maintained in kreisel tanks at the Griffith Sea Jellies Research laboratory, Sea World Australia. Ninety-two parasitic anemones were collected from the medusae. The anemone appears to be a new species of the genus Peachia and this is the first Australian report of them infecting a Chrysaora species. The prevalence of infection was 84%, and the mean intensity of infection was 4.5 ±0.6.
One heavily infected jellyfish was maintained in a kreisel and observed. The medusa became ulcerated, was castrated, and stopped swimming. Twenty-nine sea anemones survived after the host medusa died and burrowed into the sand on the bottom of the kreisel, suggesting that this interaction could be parasitoidism.