Kingdom: Animalia
Phylum: Cnidaria
Class: Scyphozoa
Order: Semaeostomeae
Family: Cyaneidae
Genus: Cyanea
Species: C. capillata
Binomial Name: Cyanea capillata
The Lion's mane jellyfish (Cyanea capillata) is named for its trailing tentacles that look like a lion's mane. The body of the jellyfish has a radial symmetry pattern. They vary greatly in size, their bell can grow up to 2 metres and is divided into 8 lobes, each lobe contains about 70 to 150 trailing tentacles. Closer to its mouth the number of tentacles can reach 1200. Their trailing tentacles can grow to up to 30 metres long, making it one of the longest animals in the world.
The Lion's Mane Jellyfish glides vertically to move around within the water. It only moves horizontally depending on the wind and water currents. Unlike other jellyfish species, the lion's mane often lives far from the shore. Towards the end of their lifespans as they become less resilient, however, they will move into shallow waters in order to avoid rowdy ocean currents.
The jellyfish is considered one of the oldest forms of animal life. It's oldest ancestors is believed to have lived 500-700 million years ago making them 3 times as old as the first dinosaurs. Of all types of animals only sponges are considered to have been earlier in their development. Some of the closest ancestors to the Lion's mane jellyfish of the Semaeostomeae order are other types of jellyfish found in the Hydrozoa class. Other common ancestors of all jellyfish are different types of corals and anemones who are all part of the Cnidaria phylum, one feature that all of it's common ancestors of the cnidaria phylum have in common is a specialized cell that is specifically designed for stinging to help it capture its prey.
The Lion's Mane Jellyfish has 8 lobes that are obvious to the naked eye. Some of these lobes have things that are used for sensing things and balance, the ends of certain lobes even have light receptors.
The smaller Lion's mane jellyfish range from a milky white color to a mustard yellow. The larger ones vary in color from a deep brick red to a dark purple. The change in coloration is mainly due to the depth at which the jellyfish lives. It is believed that these certain colors help the jellyfish capture various prey.
The enormous tentacles of the Lion's mane jellyfish are lined with a massive amount of cnidocytes that will be triggered whenever touched. These cnidocytes help the jellyfish deliver a sting to any prey or predators that it has to defend itself against.
Reproduction for a lion's mane jellyfish could be either sexual or asexual. It carries both eggs and sperm and doesn't require a mate to procreate. Babies emerge over the summer and autumn where they have a high mortality rate, only less than have of them are able to survive. The life cycle of the lion's mane jellyfish consists of four stages. At first the female jellyfish takes its fertilized eggs on its tentacles which then develop into larvae. When the larvae mature, they are let go and put onto a hard surface where they will then develop into polyps. During this stage which can last several months or even years, asexual reproduction occurs. The polyps form small sacks of creatures called ephyraes which then separate into individuals who will grow into the medusa stage from where they will grow to become full grown adults. The lifespan of the lion's mane jellyfish is around a year long.
The lion's mane jellyfish is able to catch its prey using its tentacles. When the prey comes in contact with the tentacles, the jellyfish's tentacles will secrete nematocysts which will then paralyzes the prey. The paralyzed prey is then moved into the mouth using the tentacles or the oral arms. Once the prey has been put into the mouth, the digestion cavity takes over. This digestive cavity includes the gullet, stomach, intestine and an opening for the anus and mouth. Nutrients from the digested food are taken by the gastrodermal lining of the gastrovascular cavity which functions for both digestion and distribution of the nutrients.
The lion's mane jellyfish does not have a real circulatory system, instead it is water based. The water around the animal contains enough oxygen and nutrients for the jellyfish to survive. The cells touching the water are able to take these items in. The lion's mane jellyfish has a very thin layer of covering of cells that allow the animal to absorb the oxygen and nutrients from the water. These nutrients are absorbed in the gastrovascular cavity where they are spread from the gastrodermis to the mesoglea and onto the epidermis.
The Lion's mane jellyfish does not have a real respiratory system, instead it goes through respiration by diffusion. The jellyfish has a thin tissue that makes it easier for oxygen to diffuse into its cells. Their body consists of an outer layer of tissue, called the epidermis and an inner layer of tissue, called the gastrodermis. The two layers of tissue sandwich an elastic, jellylike substance called the mesoglea. The mesoglea consists of nonliving material secreted by the living tissue requiring little to no oxygen.
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