Introduction
Are Octopus and Squid are same animals? Its answer is no. They are not the same. But Octopus and squid are cousins because both creatures are part of the group Cephalopoda. Cephalopoda is a group of marine molluscs which includes squid, Octopus, and snails. Snails have shells for their protection, but with time, octopuses and squid evolved to have bodies that don’t require the use of hard shells for protection. Squids and octopuses have prominent hands or tentacles that extend from their body. There is a total of 300 species of squids in the world, and also 300 species of Octopus found globally. Both animals have tentacles, but the arms of the Octopus are more flexible than squid.
Squid vs. Octopus
These cousins have many similarities but also have many differences. Squid and Octopus have tentacles and a high level of intelligence. Both have ink sacs that can expel ink from them and help in camouflage. A squid is larger compared to an octopus, and the weight of a squid is more than that of an octopus. Octopuses like to live in coral reefs and seabed, while squids live in the open ocean and in the deep ocean. Squids can live up to 15 years, while octopuses have less life span.
Difference Between Squid and Octopus in Tabular Form
| Parameters of Comparison | Squid | Octopus |
| Definition | Squid is a sea animal with a long body and ten arms situated around the mouth. | Octopus is a sea animal and molluscs with eight muscular arms with two suckers. |
| Arms and Tentacles | Squids have a combination of arms and tentacles. | Octopus has arms, and tentacles are present on the tip of suckers, but the arms are covered in suckers. |
| Lifespan | Octopus lice on the seabed, on coral reefs. | Octopus can live up to 1-3 years. |
| Habitat | The weight of squid is less than 1 gram to 1 ton. | Squids live in the deep ocean. |
| Size | Squids can grow up to 5 inches to 43 feet. | Octopus can grow up to 1 inch to 30 feet. |
| Weight | The weight of an octopus is 1 gram to 600 pounds, which means nearly 270 kilograms. | A squid is a sea animal with a long body and ten arms situated around the mouth. |
| Diet | Squids catch fish and shrimp with their tentacles and eat their prey in chunks. | Octopus-like worms. Prawns, fish to eat. They paralyzed their prey with toxic saliva. |
| Geographical Distribution | Squids can be found in the salty water of tropical areas. | Octopus can be found in the salty water of tropical areas. |
| Species | There are exactly 298 species of squids found globally. | There are around 300 species of octopodes all over the world. |
| Nature | Squids live in a group; they are maybe solitary by nature. | Octopi likes to live alone. |
| Shell | Octopuses don’t have any shells or stiff bones in their whole body. | Octopuses don’t have any shells or stiff bones in their whole body. |
| Camouflage | Squids use ink in their ink sac to camouflage. | Octopuses use ink in their ink sac to camouflage as well as change the shape and texture of their skin to hide. |
| Use as food | The arms and tentacles of squid are edible; black pasta is cooked using squid ink. The famous dish od squid is known as Calamari. | Octopuses use ink in their ink sac to camouflage as well as change its shape and texture of their skin to hide. |
| Contents in cooked | Cooked squid contains 198 mg of cholesterol and 13.2 gm of protein. | Cooked octopus contains 139 calories; it is great source of vitamins B3, B12, potassium, and phosphorous. |
| Kingdom | Animalia | Animalia |
| Order | Teuthida | Octopoda |
| Class | Cephalopoda | Cephalopoda |
| Subclass | Coleoidea | Coleoidea |
| Colour of blood | Blue | Blue |
What is a Squid?
A squid is a marine animal with a soft, elongated body, large eyes, eight arms, and two tentacles. Squids can change color to camouflage and for signaling. Squids can move in different ways. Lateral fins do the movement on the side of the trunk; this movement is called jetting. Squids used slow jetting for ordinary locomotion and ventilation of the gills. While fast jetting is used for an escape. In fast jetting, radial muscles in the mantle wall are involved. In slow jetting, the circular muscles in the mantle wall are used. Squids can grow up to 5 inches to 43 feet; their weight is 1 gram to 1 ton. Their blood is blue. Squids are found in the deep ocean in groups. In the world, there are 298 species of squid. Five years is the life span of squid, but the oldest squid that survived is recorded at 15 years old. Squids can be edible, and their ink is used to color black pasta. Only the bone-named pen cannot be cooked. In Japan, squid is eaten in the form of sushi. The most famous dish of squid that can be eaten worldwide is Calamari, adapted from Italian into English. The whole body is edible of squid. It is stuffed and cut into flat pieces or sliced. The dishes made from the arms and tentacles of squid are also delicious. The cooked squid contains 198 milligrams of cholesterol and 13 grams of protein.
Types of Squid
There are nearly 298-300 species of squids found in the world. But here we are discussing the top 5 species of squids:
Colossal Squid
This is one of the largest species of squid with a length of 30-33 feet, and the largest colossal squid has a weight of around 1090 pounds, which means 495 kilograms. The habitat of this squid is the Southern Ocean to Antarctica, 13000 feet deep.
Giant Squid
The length of a giant squid can reach up to 39-43 feet. This length is responsible for its name. Their weight can reach up to 606 pounds. In kilograms, it is 274 kilograms. These squids live in the deep sea between deepness of 989-3280 feet, and hence, it isn't easy to see them. But the first picture of a live giant squid was taken in 2004 by Japanese Scientists. Giant squids are solitary hunters who catch their prey using two tentacles.
Robust Clubhook Squid
This is rare species of squid found in the Northern Pacific Ocean at depths of 100-1700 feet. They can grow up to 13 feet in length. The Robust Clubhook squid has a weight of around 110 pounds, which means 49 kilograms. The food of this species is small fishes and jellyfish, and it is preyed on by sperm whales, sharks, and fur seals. Robust Clubhook is the name given for its distinctive tentacular clubs.
Humboldt Squid
Humboldt squids are also known as Jumbo squid, and they can grow up to 7 feet in length. Their weight can reach up to 110 pounds, which means 49 kilograms. They are found in groups in the eastern Pacific Ocean. Humboldt squids live in the deep ocean at a depth between 600-12300 feet. They are expert swimmers and can swim up to 15 miles per hour. They feed on small fish and other molluscs. They have suckers on their arms, and each sucker has a ring of sharp teeth. There is one great thing about their body is they can produce red and white light across their entire body. These lights are used to communicate and also use as a warning signal.
Dana Octopus Squid
The Dana octopus squid can grow up to 7.5 feet long, and its weight can reach up to 356 pounds, which means 161 kilograms. This is a massive weight in all squids. These species live in polar seas at a depth of 2400 feet. Dana octopus squids are skilled swimmers. They are the prey of sharks. To catch prey, dana octopus squid uses their tentacles and sharp beak. This squid emits blinding flashes of light to stun and disorient its prey when it attacks. This is the best protection for this species.
What is Octopus?
Octopus is a marine animal with a soft body, and it is an eight-limbed mollusc of the order Octopoda. There are 300 species of Octopus present worldwide. Octopuses can grow up to 30 feet, and they weigh nearly 270 kilograms. The habitat of octopodes is seabed coral reefs. They like to live alone; octopuses do not live in groups. In mythology, octopuses appear as sea monsters like the Kraken of Norway and the Gorgon of ancient Greece. Octopuses have eight arms with suckers. The tentacles are present on the tip of every sucker. The arms are surrounded by mouths and attached to each other. The eyes of an octopus are large in size and present at the top of the head. Their blood is blue in color, and their circulatory system is closed circulatory system, which means the blood remains inside blood vessels. The life span of an octopus is short. They can live for 1-3 years. Like squid, Octopus is also used as food worldwide. Octopus is a rich source of vitamins and minerals and also a source of complete protein for people who are trying to manage weight. In Japan, Octopus is a commonly used ingredient in their dishes. They also used Octopus in a dish named Sushi. In Maldives, the tentacles of an octopus are cooked with curry leaves, chili, garlic, onion, pepper, and coconut oil. Octopus is a common food in Tunisia. People of Tunisia like to eat the arms of an octopus. Octopus contains 56 calories per 100 grams, and also it is a rich source of vitamins B3, B12, potassium, and phosphorous.
Types of Octopus
There are around 300 species of octopus found globally, but here we are discussing the topmost species of them:
Mimic Octopus
This species is especially known as a hunter who primarily dines on small fish. As in their name, these octopodes are skilled actors. This means creatures imitate fiercer, venomous animals to scare away threats. They can grow up to 2 feet and are found in the Indo-Pacific Ocean. This species was discovered in 1998.
Caribbean Reef Octopus
This species is found in the Pacific Ocean and in the Neotropical region. The Caribbean reef octopus is nocturnal. They hunt at night for crabs, lobsters, and shrimp. This species of octopus has the ability to change its color to camouflage. They can grow up to 2 feet. They are the prey of sharks and stingrays. The Caribbean reef octopus was discovered in 1929.
Common Octopus
This species is found all over the world. That’s why their name is Common Octopus. They can grow up to 4.3 feet. The special ability of Common octopuses is that they have a soft body, that’s why they can squeeze their body and can go through any small place. Common octopuses use this ability at times of protection. They eat crabs, crayfish, and other molluscs. Their life span is around 1 to 2 years.
Giant Pacific Octopus
As their name suggests, this species can grow up to 16 feet. Because of this size, they are also compared with the monster octopus in ancient stories. Giant Pacific octopuses are found in the North Pacific, the U.S., Eastern China, and Japan. This species of Octopus has nine brains. They eat shrimps, crabs, small sharks, and other octopi. Their life span is 3 to 5 years. The giant Pacific Octopus was discovered by a Danish scientist in 1857.
Atlantic Pygmy Octopus
This dwarf species of octopus has a length of 3.5 inches. They are found in the Atlantic Ocean, in Mexico, and in the Caribbean. Atlantic Pygmy octopus has ink sacs to escape from danger. Its color is reddish orange. They eat clams and small aquatic creatures. This species was discovered in 1929.
Main Difference Between Squid and Octopus in Points
- A squid is an aquatic animal with 10 arms, whereas an octopus is an aquatic animal with 8 arms.
- Squids have tentacles on their arms, whereas octopuses have suckers on their arms, and tentacles are present at the tip of suckers.
- Squids live in the deep ocean, whereas octopuses live on seabed and on coral reefs.
- Squids can grow up to 43 feet, whereas octopuses can grow up to 30 feet.
- The weight of squid is nearly 1 gram to 1 ton, whereas octopus weighs around 1 gram to 600 pounds.
- There are 298 species of squids present, whereas 300 species of octopodes are found worldwide.
- Squid uses ink in their ink sac to camouflage, whereas octopus can change their color to camouflage and also use ink.
- The color of the blood of both is blue.
Conclusion
Octopus and squid are both aquatic animals, and both are molluscs. Squids like to live in groups, while octopodes live alone. Squids have a large size compared to octopodes. Both are edible worldwide. Octopus is a rich source of vitamins. Squid and octopuses have ink sacs that they use for their protection and for camouflage. There are more species of Octopus compared to squid. Squids can be found in the deep ocean, while octopuses can be seen on coral reefs and on the seabed.
References
- What’s the Difference? Octopus vs. Squid | How Many Tentacles on Squid. (2020, January 22). National Marine Sanctuary Foundation. https://marinesanctuary.org/blog/what-is-the-difference-between-octopus-and-squid/
- Squid vs. Octopus: Understand The Differences. (2022, March 19). Dictionary.com. https://www.dictionary.com/e/squid-vs-octopus/
- Squid - Wikipedia. (2018, December 9). Squid - Wikipedia. https://en.wikipedia.org/wiki/Squid
- Squid. (n.d.). Animals. https://www.nationalgeographic.com/animals/invertebrates/facts/squids
- Octopus - Wikipedia. (2014, February 4). Octopus - Wikipedia. https://en.wikipedia.org/wiki/Octopus
- Octopus. (n.d.). Animals. https://kids.nationalgeographic.com/animals/invertebrates/facts/octopus
- Godfrey-Smith, P. (n.d.). The Mind of an Octopus. Scientific American. https://doi.org/10.1038/scientificamericanmind0117-62
