''Acanthochitona garnoti'', the spiny chiton, is a medium-sized

polyplacophoran Chitons () are marine (ocean), marine molluscs of varying size in the class (biology), class Polyplacophora (), formerly known as Amphineura. About 940 Extant taxon, extant and 430 fossil species are recognized. They are also sometimes known ...

mollusc Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is esti ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Acanthochitonidae, found on the coast of southern Africa.

Description

This species is conspicuous for the nine paired tufts or rosettes of long glassy spines that decorate its

girdle A belt, especially if a cord or rope, is called a girdle if it is worn as part of Christian liturgical vestments, or in certain historical, literary or sports contexts. Girdles are used to close a cassock in Christian denominations, including th ...

. Between the tufts, the girdle bears many smaller spicules. The spicules are sharp, and if carelessly handled, easily penetrate the human skin, where they detach and remain, becoming painfully irritating. The

valve A valve is a device or natural object that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways. Valves are technically fittings ...

s are of a dull brown color and marked with oblique pale stripes. They are largely concealed by the girdle. Adult size is 30–45 mm.

Distribution and habitat

''A. garnoti'' occurs along the south coast of Africa, from

Cape Columbine Cape Columbine is well known for its lighthouse, the last staffed lighthouse built on the South African coast The Cape Columbine Lighthouse was commissioned on October 1, 1936. Both the headland and lighthouse derive their name from the barque C ...

Namibia Namibia (, ), officially the Republic of Namibia, is a country in Southern Africa. Its western border is the Atlantic Ocean. It shares land borders with Zambia and Angola to the north, Botswana to the east and South Africa to the south and ea ...

to the south coast of

KwaZulu-Natal KwaZulu-Natal (, also referred to as KZN and known as "the garden province") is a province of South Africa that was created in 1994 when the Zulu bantustan of KwaZulu ("Place of the Zulu" in Zulu) and Natal Province were merged. It is locate ...

South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...

. It can be found on exposed rock surfaces high up in the inter-tidal zone, a location that is unusually far from the water for chitons.

Ecology

The species is mostly active at night, foraging by grazing in a small radius (10–30 cm) around its location. Both the range and the pattern of foraging are adapted to the type of substrate, with different strategies adopted on rocky versus sandy ground.

References

{{Taxonbar, from=Q3795668 Acanthochitonidae Molluscs of Africa Molluscs of the Atlantic Ocean Molluscs of the Indian Ocean Chitons described in 1825 Taxa named by Henri Marie Ducrotay de Blainville