Chiton olivaceus | |
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Dorsal view of Chiton olivaceus from Sicily. Museum specimen | |
Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Polyplacophora |
Order: | Chitonida |
Family: | Chitonidae |
Genus: | Chiton |
Species: | C. olivaceus |
Binomial name | |
Chiton olivaceus Spengler, 1797 | |
Synonyms | |
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Chiton olivaceus, the green chiton, is a species of chiton, a marine polyplacophoran mollusk in the family Chitonidae, the typical chitons. [1] [2]
Chiton olivaceus can reach a length of 32–40 millimetres (1.3–1.6 in) and a width of about 16 millimetres (0.63 in). These large chitons have carinate plates with strong ribs. The shell is oblong and oval. In the front and rear plates ribs have a radial pattern. The intermediate valves show a sharp beak and rounded sutural plates. Colors are very variable, ranging from olive-gray (hence the common name) to yellow-brown, sometimes black, orange, red or yellow. The girdle surrounding all of the valves is quite large and covered by bristles and scales. [3] [4] [5]
The teeth of these grazers of algae [6] are composed of magnetite,[ citation needed ] the hardest material usable by a living being.
This species is common in the Mediterranean sea around Italy and Greece, but can also to be found in the nearby Atlantic Ocean. [7]
Chiton olivaceus occur on a solid substrate, particularly stones and rocks, in the zones of sweeping of the waves, at a low depth. [3]
A seashell or sea shell, also known simply as a shell, is a hard, protective outer layer usually created by an animal or organism that lives in the sea. Most seashells are made by mollusks, such as snails, clams, and oysters to protect their soft insides. Empty seashells are often found washed up on beaches by beachcombers. The shells are empty because the animal has died and the soft parts have decomposed or been eaten by another organism.
Bivalvia or bivalves, in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of aquatic molluscs that have laterally compressed soft bodies enclosed by a calcified exoskeleton consisting of a hinged pair of half-shells known as valves. As a group, bivalves have no head and lack some typical molluscan organs such as the radula and the odontophore. Their gills have evolved into ctenidia, specialised organs for feeding and breathing.
Chitons are marine molluscs of varying size in the class Polyplacophora, formerly known as Amphineura. About 940 extant and 430 fossil species are recognized.
The gumboot chiton, also known as the giant western fiery chiton or giant Pacific chiton, is the largest of the chitons, growing to 36 cm (14 in) and capable of reaching a weight of more than 2 kg (4.4 lb). It is found along the shores of the northern Pacific Ocean from Central California to Alaska, across the Aleutian Islands to the Kamchatka Peninsula and south to Japan. It inhabits the lower intertidal and subtidal zones of rocky coastlines. The gumboot chiton's appearance has led some tidepoolers to refer to it, fondly, as the "wandering meatloaf". The name "gumboot chiton" seems to derive from a resemblance to part of a rubber Wellington boot or "gum rubber" boot.
Chiton glaucus, common name the green chiton or the blue green chiton, is a species of chiton, a marine polyplacophoran mollusk in the family Chitonidae, the typical chitons. It is the most common chiton species in New Zealand. Chiton glaucus is part of a very primitive group of mollusc with evidence of being present in up to 80 million years of the fossil record.
A valve is each articulating part of the shell of a mollusc or another multi-shelled animal such as brachiopods and some crustaceans. Each part is known as a valve or in the case of chitons, a "plate". Members of two classes of molluscs, the Bivalvia (clams) and the Polyplacophora (chitons), have valves.
Pecten jacobaeus, the Mediterranean scallop, is a species of scallop, an edible saltwater scallop, a marine bivalve mollusc in the family Pectinidae, the scallops.
Brachiopods, 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.
Chiton tuberculatus, the West Indian green chiton, is a species of chiton, a marine polyplacophoran mollusk in the family Chitonidae, the typical chitons.
Acanthopleura granulata, common name the West Indian fuzzy chiton, is a medium-sized tropical species of chiton. This type of chiton's activity does not depend on spring-neap oscillations leading to lower locomotion loss. Its morphology is different from usual chitons as it has a fifth valve, which is split into halves.
Acanthochitona fascicularis, the Velvety mail shell, is a common chiton in the family Acanthochitonidae.
Fabulina fabula, the bean-like tellin, is a species of marine bivalve mollusc in the family Tellinidae. It is found off the coasts of northwest Europe, where it lives buried in sandy sediments.
Orthasterias is a genus of sea stars in the family Asteriidae. Orthasterias koehleri, the rainbow star or red-banded sea star, is the only species in the genus. It is found in the North Pacific Ocean.
Gigantoproductus giganteus is an extinct species of brachiopods in the family Monticuliferidae, known only from its fossil remains. It was a marine invertebrate found on the seabed in shallow seas. It evolved during the Carboniferous period and it is believed to be the largest brachiopod that has ever existed.
Barbatia barbata is a species of ark clam, a marine bivalve mollusk in the family Arcidae, the ark clams.
Dosinia exoleta, common name the rayed artemis, is a saltwater clam, a marine bivalve mollusc in the family Veneridae, the venus clams.
Plaxiphora albida, the white Plaxiphora chiton, is a species of chiton in the family Mopaliidae.
Argyrotheca is a genus of very small to minute lampshells. All species share a large pedicel opening, one ridge on the inside of the pedunculate valve, pits in a diamond pattern on the inside of both valves, and without radial ridges that end in tubercles. It occurs in depths between 6 and 1300 m. It is known since the latest Cretaceous.
Plaxiphora caelata is a small chiton in the family Mopaliidae, endemic to the main islands of New Zealand, Stewart Island and the Chatham Islands.
Acanthochitona crinita is a species of marine chiton in the family Acanthochitonidae. It is found on rocky coasts in the northeastern Atlantic Ocean, the North Sea and the Mediterranean Sea.