A cephalopod / ˈ s ɛ f ə l ə p ɒ d / is any member of the molluscan class Cephalopoda / s ɛ f ə ˈ l ɒ p ə d ə / (Greek plural κεφαλόποδες, kephalópodes; "head-feet") [3] such as a squid, octopus, cuttlefish, or nautilus.

All extant cephalopods have a two-part beak, or rostrum, situated in the buccal mass and surrounded by the muscular head appendages. The dorsal (upper) mandible fits into the ventral (lower) mandible and together they function in a scissor-like fashion.

Tentacles (cephalic in origin) surround the mouth on the head for capturing prey. They often bear suckers, sometimes hooks and, in some groups, a pair of retractile tentacles (arms) are found. Cephalopods have powerful, modified jaws (beaks) and a small radulae.

May 31, 2024 · Many muscular appendages extend from the head and surround the mouth of cephalopods. In coleoids, they are usually eight to ten in number and serve multiple purposes, like feeding, movement, and reproduction. There are two distinctly long arms called tentacles that lengthen in as little as 15 milliseconds.

Dec 21, 2024 · Surrounding the mouth are eight long, prehensile arms, provided with suckers in octopuses and argonauts (order Octopoda), or eight arms and two tentacles, equipped with horny ringed suckers bearing teeth or hooks in squids and cuttlefishes (orders Teuthoidea and Sepioidea). The primitive Nautilus has about 90 small suckerless appendages.

Cephalopods span across the depths of all five oceans, which also leads to differences in prey types. In other creatures, such differences lead to different mouth mechanisms — sharks do not eat the same way clownfish do, and parrots snack differently than hummingbirds.

May 6, 2021 · The oral cavity of cephalopods is a muscular mass that contains the mouth, beak , and raspy tongue (radula ) and serves as the entry point to the digestive system . The beak is made up of chitin, which is hard, and resembles that of a parrot, although with an underbite.

The cephalopod mouth contains strong beak-like jaws that are used to deliver a lethal bite to prey items as well as shred them; a radula is also present. Salivary glands can produce highly toxic venoms in some squids and octopi, and ink sacs are present in most taxa except Nautilus .

Cephalopods are characterized by a well-developed head with a circumoral (surrounding the mouth) arrangement of arms that bear suckers and/or hooks (except in Nautilus). The mouth has chitinous beak-like jaws; as in other molluscs a chitinous tongue-like radula (band of teeth) is present in most species.

Jan 3, 2025 · Models of possible life appearance of various ammonites showing diversity. The top row are typical monomorph ammonites while the rest are heteromorph ammonites. Not to scale. See also labeled photo.