Molluscs in the context of Cephalopod

Shellfish, in colloquial and fisheries usage, are exoskeleton-bearing aquatic invertebrates used as food, including various species of molluscs, crustaceans, and echinoderms. Although most kinds of shellfish are harvested from saltwater environments, some are found in freshwater. In addition, a few species of land crabs are eaten, for example Cardisoma guanhumi in the Caribbean. Shellfish are among the most common food allergens.

Due to narrowing in the meaning of the English word fish over the centuries, shellfish no longer fall under what is usually considered fish. Most shellfish are low on the food chain and eat a diet composed primarily of phytoplankton and zooplankton. Many varieties of shellfish, and crustaceans in particular, are actually closely related to insects and arachnids; crustaceans make up one of the main subphyla of the phylum Arthropoda. Molluscs include cephalopods (squids, octopuses, cuttlefish) and bivalves (clams, oysters), as well as gastropods (aquatic species such as whelks and winkles; land species such as snails and slugs).

Terrestrial molluscs or land molluscs (mollusks) are an ecological group that includes all molluscs that live on land in contrast to freshwater and marine molluscs. They probably first occurred in the Carboniferous, arising from freshwater ones.

The coelom (or celom) is the main body cavity in many animals and is positioned inside the body to surround and contain the digestive tract and other organs. In some animals, it is lined with mesothelium. In other animals, such as molluscs, it remains undifferentiated. In the past, and for practical purposes, coelom characteristics have been used to classify bilaterian animal phyla into informal groups.

Teuthology, from Ancient Greek τευθίς (teuthís), meaning "squid", and λόγος (lógos), meaning "study", is the study of cephalopods, which are members of the class Cephalopoda in the phylum Mollusca. Some common examples of cephalopods are octopus, squid, and cuttlefish. Teuthology is a large area of study that covers cephalopod life cycles, reproduction, evolution, anatomy, and taxonomy.

Teuthology is a specific branch of malacology, the study of molluscs. A teuthologist is a scientist who studies teuthology.

Brachiopods (/ˈbrækioʊˌpɒd/), phylum Brachiopoda, are a phylum of animals that have hard "valves" (shells) on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear end, while the front can be opened for feeding or closed for protection.

Two major categories are traditionally recognized, articulate and inarticulate brachiopods. The word "articulate" is used to describe the tooth-and-groove structures of the valve-hinge which is present in the articulate group, and absent from the inarticulate group. This is the leading diagnostic skeletal feature, by which the two main groups can be readily distinguished as fossils. Articulate brachiopods have toothed hinges and simple, vertically oriented opening and closing muscles. Conversely, inarticulate brachiopods have weak, untoothed hinges and a more complex system of vertical and oblique (diagonal) muscles used to keep the two valves aligned. In many brachiopods, a stalk-like pedicle projects from an opening near the hinge of one of the valves, known as the pedicle or ventral valve. The pedicle, when present, keeps the animal anchored to the seabed but clear of sediment which would obstruct the opening.

Siliqua is a genus of saltwater razor clams, marine bivalve molluscs in the family Pharidae, the razor clams and jackknife clams.

Terrapins or water tortoises are a group of several species of aquatic reptile of the order Testudines living primarily in fresh or brackish tidal waters, but have the clawed feet of tortoises and not flippers of marine turtles. In American English, they are referred to as marsh, pond, or tide-water turtles, with some species called pond sliders as well. Whereas tortoises are almost strict herbivores and frugivores — largely feeding on flowers, grasses, leaves, and fallen fruit — a great many terrapins are mainly carnivorous — largely feeding on amphibians, arthropods, freshwater fish, and molluscs — though some are herbivores. Terrapins are identified primarily with the taxonomic family Emydidae, but do not form a single taxon and may not be closely related, with some belonging to the families Geoemydidae, Pelomedusidae, Podocnemididae, and Chelydridae. Though primarily aquatic, terrapins do relatively frequently come to land for many reasons, but particularly to warm up by basking in the sun.

The Dreissenidae are a family of small freshwater aquatic bivalve molluscs, commonly called mussels although not at all closely related to true mussels. The shells of these bivalves are shaped somewhat like those of true mussels, which they also resemble in attaching themselves to a hard substrate such as stone using a byssus; however, this group is more closely related to the venus clams (Veneridae).

Flesh is any aggregation of soft tissues of an organism. Various multicellular organisms have soft tissues that may be called "flesh". In mammals, including humans, flesh encompasses muscles, fats and other loose connective tissues, but sometimes excludes non-muscular organs (liver, lung, spleen, kidney) and typically discarded parts (hard tendon, brain tissue, intestines, etc.). More generally, it may be considered the portions of the body that are soft and delicate. In a culinary context, consumable animal flesh is called meat, while processed visceral tissues are known as offal.

In particular animal groups such as vertebrates, molluscs and arthropods, the flesh is distinguished from tougher body structures such as bone, shell and scute, respectively. In plants, the "flesh" is the juicy, edible structures such as the mesocarp of fruits and melons as well as soft tubers, rhizomes and taproots, as opposed to tougher structures like nuts and stems. In fungi, flesh refers to trama, the soft, inner portion of a mushroom, or fruit body.

The gizzard, also referred to as the ventriculus, gastric mill, and gigerium, is an organ found in the digestive tract of some animals, including archosaurs (birds and other dinosaurs, crocodiles, alligators, pterosaurs), earthworms, some gastropods, some fish, and some crustaceans. This specialized stomach constructed of thick muscular walls is used for grinding up food, often aided by particles of stone or grit. In certain insects and molluscs, the gizzard features chitinous plates or teeth.

The non-marine molluscs of Uganda are the molluscan fauna of Uganda (wildlife of Uganda). Since Uganda is a land-locked country, there are no marine species present. A number of species of freshwater and land molluscs are found in the wild in Uganda.

66 native molluscs of Uganda were listed in 2010 IUCN Red List of Threatened Species.