Clione limacina

The sea angel lives in very cold water.

It has no hard shell. It uses two wings to swim. It flaps its wings to move up or down.

This animal has a special way to eat. It uses tiny arms to grab its food. It pulls the food out of a shell. Then it swallows it whole.

Sea angels can live without food for a year. They can even eat other tiny things to stay alive.

Whales and fish like to eat them too. They are small but very special.

The sea angel is a tiny animal that lives in cold water. It lives in the Arctic Ocean and the North Atlantic Ocean. You might know it by its other name, Clione limacina. Unlike many other sea snails, it has no shell. This makes it a gymnosomatous, which means it is shell-less.

To move through the water, it flaps two wings. It uses these wings to swim up or stay at one depth. It also has two statocysts. These are tiny organs that sense gravity. They help the animal stay upright while it swims.

Sea angels have a very special way of eating. They mostly eat other sea butterflies. The sea angel uses three pairs of small arms called buccal cones. These arms grab the prey. Then, it uses sharp hooks to pull the body out of the shell. It swallows the food whole.

These animals can go a long time without food. They can survive for one year without eating! This helps them when their main food is not around. Many animals like to eat them, including whales and salmon.

The sea angel is a tiny, amazing creature of the deep. It is also known as Clione limacina or the naked sea butterfly. This animal is a pelagic sea slug. That means it lives in the open ocean. It can be found from the very surface down to great depths. Most sea slugs have hard shells to protect them. However, this species is a gymnosomatous. This scientific term means it lives without a shell.

Swimming through the cold water requires a special way of moving. The sea angel uses two wings to move. It beats these wings to swim upward. It can also use them to stay at one depth. To keep from tipping over, it uses two statocysts. These are gravity-sensing organs. They help the animal stay upright by using its tail. This keeps the sea angel steady as it glides through the ocean.

People have studied these creatures for a long time. Friderich Martens first described them in 1676. This was a big discovery for science. It was the first shell-less pteropod ever described. Later, Constantine Phipps also worked with this species. The sea angel lives in very cold places. You can find them in the Arctic Ocean. They also live in the North Atlantic Ocean. They can even swim as far south as the Sargasso Sea.

There are many interesting facts about their size and life. There are two main subspecies of Clione limacina. The northern subspecies lives in the coldest water. It can grow to be 4 centimeters long. This makes it the largest sea angel. The southern subspecies is much smaller at only 1 centimeter. These animals are hermaphrodites. This means they have both male and female parts. They breed during the spring and summer. Their eggs are very small, only about 0.05 millimeters.

Sea angels have a very unique way of eating. They mostly eat other sea butterflies called Limacina. The sea angel uses three pairs of buccal cones. These are small arms near its mouth. The arms grab the shell of its prey. Then, the sea angel uses tiny hooks to pull the body out. It swallows the whole body at once. This is a very fast way to eat. They can even survive for one year without food. This helps them when their prey is not around.

Clione limacina is a fascinating marine mollusk often called the sea angel or the naked sea butterfly. This creature is a pelagic sea slug, meaning it lives in the open water column rather than on the ocean floor. It can be found from the ocean surface to much greater depths. Most sea slugs possess a protective shell, but Clione limacina is a gymnosomatous. This scientific term describes a pteropod that lives without a shell. These animals are vital parts of cold-water ecosystems in the Arctic and North Atlantic Oceans.

To move through the water, the sea angel uses a specialized method of swimming. It possesses two wing-like structures that it beats to move upward. These wings also allow the animal to maintain a constant depth in the water. Because swimming can cause them to tilt, they use two statocysts to stay balanced. Statocysts are small, gravity-sensing organs that help the animal sense its position. By using these organs, the sea angel can use its tail to correct its posture. This process ensures the creature remains in an upright position while gliding.

Scientists have studied these unique mollusks for several centuries. Friderich Martens first described the species in 1676. This was a significant moment because it was the first gymnosomatous pteropod ever recorded. The species is categorized into different subspecies based on their environment and size. The northern subspecies lives in the coldest waters and can reach a length of 4 centimeters. This makes it the largest of the sea angels. In contrast, the southern subspecies is much smaller, measuring only about 1 centimeter.

The genus Clione contains other related species found in different parts of the world. For example, Clione elegantissima lives in the cold North Pacific, specifically near the Gulf of Alaska. Clione okhotensis is found in the Okhotsk Sea, where it overlaps with C. elegantissima. There is also Clione antarctica, which inhabits the waters around Antarctica. Each of these species has a distinct maximum size. C. elegantissima grows up to 2 centimeters, while C. okhotensis reaches 1.5 centimeters. C. antarctica is even smaller, reaching only 1 centimeter.

The feeding mechanism of Clione limacina is truly extraordinary. Adult sea angels almost exclusively prey on other sea butterflies, specifically the genus Limacina. Their mouth, or buccal apparatus, consists of three pairs of buccal cones. These cones act like small arms to grab the shell of the prey. Once the prey is positioned correctly, the sea angel uses chitinous hooks. These hooks are everted, or pushed out, from specialized hook sacs. The sea angel then extracts the entire body from the shell and swallows it whole.

Survival in the Arctic requires incredible biological resilience. Adult Limacina are often absent from the water for much of the year. This leaves the sea angel without its primary food source. However, Clione limacina can survive for one entire year without eating. During these periods of starvation, they may change their diet. Studies show some individuals eat amphipods or calanoids instead. In laboratory settings, slugs that undergo long starvation periods can actually decrease in length. On average, their length has been observed to drop from 4 centimeters to 2 centimeters.

The life cycle of this species is complex and involves several stages. In regions like Svalbard, the life cycle appears to last at least two years. Clione limacina is a simultaneous hermaphrodite, meaning it possesses both male and female reproductive organs at the same time. They breed during the spring and summer months. The eggs produced are very small, measuring approximately 0.05 millimeters. While the earliest larvae feed on phytoplankton, they switch to eating Limacina as they grow. Interestingly, large sea angels avoid eating small Limacina, including their larvae.

Clione limacina plays a significant role in the marine food web. They are prey for many planktonic feeders, including baleen whales. Because of this, sailors historically referred to them as "whale-food." Various fish species, such as the Chum Salmon, also hunt sea angels. Beyond biology, these creatures have entered popular culture. They serve as the inspiration for characters like Manaphy and Phione in Pokémon. They also appear in various video games and artistic works, proving their impact extends from the deep sea to human imagination.