Download top and best high-quality free Squid PNG Transparent Images backgrounds available in various sizes. To view the full PNG size resolution click on any of the below image thumbnail.

License Info: Creative Commons 4.0 BY-NC

Squid are cephalopods with elongated bodies, big eyes, eight limbs, and two tentacles that belong to the Decapodiformes superorder. Squid have a distinct head, bilateral symmetry, and a mantle, much like all other cephalopods. They are mostly soft-bodied, like octopuses, but they contain a tiny internal skeleton of chitin in the shape of a rod-like gladius or pen.

During the Jurassic period, squid separated from other cephalopods and now serve in a similar capacity to teleost fish as open-water predators of similar size and behavior. In the open water food web, they play an essential role. The eight arms are used to grip and manipulate prey, while the two lengthy tentacles are utilized to grasp it. The beak next chops the meal into bite-sized bits that can be swallowed. Squid are fast swimmers who use jet propulsion to propel themselves and rely on sight to seek their food. Humboldt squid have been recorded hunting collaboratively in groups, making them one of the most intelligent invertebrates. Sharks, other fish, marine birds, seals, and cetaceans, notably sperm whales, feed on them.

For concealment and signaling, squid may change color. Many species may expel a cloud of ink to distract predators, while some are bioluminescent and use their light for counter-illumination concealment.

Commercial fisheries in Japan, the Mediterranean, the southwestern Atlantic, the eastern Pacific, and elsewhere employ squid for human food. They are commonly referred to as “calamari” and are used in various cuisines across the world. Since classical times, squid have been depicted in literature, particularly in tales of enormous squid and sea monsters.

Squid belong to the Cephalopoda class, subclass Coleoidea. The squid orders Myopsida and Oegopsida belong to the Decapodiformes superorder (from the Greek for “ten-legged”). Although they are taxonomically separate from squids and have distinguishable gross anatomical characteristics, two additional orders of decapodiform cephalopods are also known as squids. The bobtail squid belongs to the Sepiolida order, whereas the ram’s horn squid belongs to the monotypic Spirulida order. The vampire squid (Vampyroteuthis infernalis), on the other hand, has more in common with octopuses than with any other squid.

Sanchez et al., 2018 provided the basis for the cladogram, which is not entirely resolved. They employed mitochondrial and nuclear DNA marker sequences in their molecular phylogeny, and they say that obtaining a strong tree “has proven exceedingly difficult.” If the Sepiidae cuttlefish are considered a kind of squid, the squids, except the vampire squid, form a clade as shown. All families not listed in those orders belong to the paraphyletic order “Oegopsida,” except Sepiadariidae and Sepiidae, which belong to “Sepiida.”

At the end of the Paleozoic, crown coleoids (the progenitors of octopuses and squid) diverged in the Permian. During the Jurassic, squid diverged, although many squid families arose during or after the Cretaceous. Both the coleoids and the teleost fish underwent a lot of adaptive radiation simultaneously, and the two current groups are quite similar in size, ecology, habitat, anatomy, and behavior. However, some fish migrated into fresh water while the coleoids stayed in the sea.

Download Squid PNG images transparent gallery.