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Chiton

Chitons, also called polyplacophorans and rarely polyplacophores, are 600 species of molluscs of the Class Polyplacophora. They glide slowly in the intertidal zone using their muscular feet.


Lined Chiton (Tonicella lineata)

Table of contents
1 Structure
2 Name
3 Activities
4 Classification
5 Miscellaneous
6 External links

Structure

The calcareous armour shell that chitons carry dorsally are protective and made of aragonite. The shell is divided into eight plates (also called valves).

Ventrally, a chiton's body is surrounded by the girdle, the ventral extension of the shell. Between the body and the girdle, there is a mantle cavity, connected to the outside by two water channels. The one on the side is the incurrent water channel. The one attached to the anus is the excurrent water channel. The majority of the body is a snail-like foot. There is a head that contains a mouth with a razor-sharp tongue called the radula. The half near the anus has gills. [1]

Name


Black Chiton (Katherina tunicata) on a stone with a
seastar

Its English name originates from a Greek word chitōn, which means "tunic" and is also the source word of the substance chitin. Its Greek-derived name Polyplacophoran comes from the words plako- (tablet) and -phoros (bearing). The Class Polyplacophora was named by J. E. Gray in 1821. Chitons were also called Cyclobranchians ("round arm") in the early 19th century.

Activities

Chitons eat algae, and sometimes bacteria, with their radula.

Predators include seagulls, seastars, crabs, fishes and sea anemones.

Classification

Classification method I [1]: The following classification is Parker, S. P. [1]: Chitons were divided into Chismobranchians and Polyplaxiphores in the early nineteenth century.

Miscellaneous


Gumboot Chiton (Cryptochiton stelleri)

The largest chiton is the pink gumboot chiton of the Pacific Northwest. [1]

External links