Haeckel's Jelly

Pseudorhiza haeckeli

Haeckel's Jelly is a species of cnidarian characterized by its round bell, which features raised, warty lumps on the upper surface. Inside the bell, there is a distinctive cross-shaped structure, while its arms curve around the bell's bottom, leading to a long, colorful tail that may vary in length due to regeneration. This jellyfish can reach a bell diameter of up to 40 cm and is reasonably transparent, making it somewhat difficult to spot in the water. Unlike many other jellyfish, it lacks tentacles, which helps in distinguishing it from similar species. Native to temperate and sub-tropical Australian marine waters, Haeckel's Jelly is typically found at depths ranging from 1 to 30 metres. It inhabits pelagic environments and is often seen in association with small fish, amphipods, and parasitic anemones that seek shelter around its arms and bell. This species is a carnivore, utilizing its stinging cells, which are only mildly irritating to humans, to capture small invertebrates and other prey. In terms of reproduction, Haeckel's Jelly is gonochoric, meaning it has distinct male and female individuals. The life cycle begins with an adult medusa laying eggs, which develop into a free-living planula, then transform into a scyphistoma, and eventually into a young medusa. Encounters with Haeckel's Jelly during dives can be intriguing, as divers may observe its unique morphology and behavior in the water column. The conservation status of this species is currently not evaluated.