Lagoon jelly, Golden medusa, Papuan jellyfish
The spotted jelly (Mastigias papua), lagoon jelly, golden medusa, or Papuan jellyfish, is a species of jellyfish from the Indo-Pacific oceans. Like corals, sea anemones, and other sea jellies, it belongs to the phylum Cnidaria. Mastigias papua is one of the numerous marine animals living in symbiosis with zooxanthellae, a photosynthetic alga.
They have a lifespan of approximately 4 months and are active primarily in mid-summer to early autumn.
Ca
CarnivoreA carnivore meaning 'meat eater' is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of a...
Pl
PlanktivoreA planktivore is an aquatic organism that feeds on planktonic food, including zooplankton and phytoplankton. Phytoplankton are usually photosynthet...
Se
SedentarySedentary animals lead such a type of lifestyle in which little to or no physical activity is done. These are mostly marine bottom-dwelling animals...
Ov
OviparousOviparous animals are female animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive...
Po
PolygynandryPolygynandry is a mating system in which both males and females have multiple mating partners during a breeding season.
No
Not a migrantAnimals that do not make seasonal movements and stay in their native home ranges all year round are called not migrants or residents.
S
starts withThe spotted jelly is so named because of the little dots that garnish its jelly. It usually measures between 3 and 10 cm (1.2–3.9 in) in length and between 2 and 7 cm (0.8–2.8 in) in diameter but some individuals can reach 30 cm (12 in) long. Contrary to most medusozoans, Mastigias papua does not have stinging tentacles. However, some individuals may contain some rare cnidocytes spread on the arms of the animal but they are inoffensive because they have lost their stinging power.
Like all medusozoans, Mastigias papua is 95% composed of water. This water similar density enables it to easily float.
Spotted jellies have been recorded many times in the Indo-Pacific Ocean, between Japan and Australia. They live in shallow waters, and for this reason they are usually found in coastal and lagoonal waters, but also in marine lakes.
This species of jellyfish is well known for living in huge groups, forming aggregates (called "smacks"). This atypical behaviour becomes a tourist attraction. The most famous spot to admire these organisms is the Ongeim’l Tketau Lake in Palau. This lake has been formed 15,000 years ago. Like many other lakes of this region, it was initially joined to the Pacific Ocean, and because of geological movements, the lake has progressively become separated from the rest of the ocean. Mastigias papua has therefore been isolated in this closed lake, with other species of medusa. Out of reach of predators, it has progressively lost its cnidocyte cells, and is therefore now totally harmless to scuba divers. The lake of Palau now counts around 10 million individuals of this species.
