Crystal Jellyfish

Aequorea vitrina

Aequorea vitrina, known as the crystal jellyfish, is a hydrozoan species characterized by its transparent, glassy appearance. Adults typically have a diameter ranging from 10 to 17 cm, with a thick center that gradually thins towards the margin. This jellyfish features 60 to 100 radial canals and over 200 tentacles, which can exceed 50 cm in length. It is important to distinguish Aequorea vitrina from Aequorea victoria, which shares a common name but is a different species. This species inhabits the neritic zone in waters around Great Britain, Ireland, and the North Sea. Aequorea vitrina is often found in coastal, pelagic environments and has been noted as an invasive species in the Sea of Marmara since 2017. Most recorded sightings occur at depths shallower than 40 meters, with a significant majority found under 30 meters. Feeding primarily on brine shrimp and rotifers, Aequorea vitrina exhibits bioluminescence due to the presence of aequorin and green fluorescent protein. The jellyfish's life cycle includes a transition from zygote to planula, then to polyp, and finally to the free-swimming medusa stage. The conservation status of Aequorea vitrina has not been evaluated by the IUCN.