Shipworm

Shipworm

Taxobox
name = Shipworm


image_caption = "Teredo" sp.
regnum = Animalia
phylum = Mollusca
classis = Bivalvia (or Pelecypoda)
ordo = Myoida
familia = Teredinidae
familia_authority = Rafinesque, 1815
subdivision_ranks = Genera
subdivision = See text.

Shipworms are not worms at all, but rather a group of unusual saltwater clams with very reduced shells, notorious for boring into (and eventually destroying) wooden structures which are immersed in sea water, including piers, docks and wooden ships. Sometimes called "termites of the sea", they are marine bivalve molluscs (Eulamellibranchiata) in the family Teredinidae, also often known as Teredo Worms.

When boring into submerged wood, bacteria in a special organ called the gland of Deshayes allows them to digest cellulose. The excavated burrow is usually lined with a calcareous tube. Shipworms have slender worm-like forms, but nonetheless possess the characteristic structures of bivalves. The valves of the shell of shipworms are small separate parts located at the anterior end of the worm, used for excavating the burrow.

The shipworms belong to several genera, of which "Teredo" is the most commonly mentioned. The best known species is "Teredo navalis". Historically, "Teredo" concentrations in the Caribbean Sea have been substantially higher than in most other salt water bodies.

Shipworms greatly damage wooden hulls and marine piling, and have been the subject of much study to find methods to avoid their attacks. These organisms are referenced in the article about copper, for the use of copper sheathing on wooden ships during the Age of Exploration, as a method of preventing damage by "teredo worms". Christopher Columbus's ships were among the earliest known to employ this defense.

Genera within the family Teridinidae

* "Bactronophorus"
* "Bankia" Gray, 1842
* "Dicyathifer"
* "Kuphus"
* "Lyrodus" Binney, 1870
* "Nausitoria" Wright, 1884
* "Neoteredo"
* "Nototeredo" Bartsch, 1923
* "Psiloteredo"
* "Spathoteredo" Moll, 1928
* "Teredo" Linnaeus, 1758
* "Teredora" Bartsch, 1921
* "Teredothyra" Bartsch, 1921
* "Uperotus"

Engineering inspiration

In the early 1800s, the behaviour and anatomy of the shipworm inspired the great British engineer Marc Brunel. Based on his observations of how the shipworm's valves simultaneously enable it to tunnel through wood and protect it from being crushed by the swelling timber, Brunel designed an ingenious modular iron tunnelling framework - a tunnelling shield - which enabled workers to successfully tunnel through the highly unstable river bed beneath the Thames. The Thames Tunnel was the first successful large tunnel ever built under a navigable river.Fact|date=June 2008

References

*
* Powell A. W. B., "New Zealand Mollusca", William Collins Publishers Ltd, Auckland, New Zealand 1979 ISBN 0-00-216906-1


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Look at other dictionaries:

  • Shipworm — Ship worm , n. (Zo[ o]l.) Any long, slender, worm shaped bivalve mollusk of {Teredo} and allied genera. The shipworms burrow in wood, and are destructive to wooden ships, piles of wharves, etc. See {Teredo}. [1913 Webster] …   The Collaborative International Dictionary of English

  • shipworm — [ship′wʉrm΄] n. any of a family (Teredinidae) of marine, bivalve mollusks with wormlike bodies: they burrow into and damage submerged wood, as of ships, pilings, etc …   English World dictionary

  • shipworm — Teredo Te*re do, n.; pl. E. {Teredos}, L. {Teredines}. [L., a worm that gnaws wood, clothes, etc.; akin to Gr. ?, L. terere to rub.] (Zo[ o]l.) A genus of long, slender, wormlike bivalve mollusks which bore into submerged wood, such as the piles… …   The Collaborative International Dictionary of English

  • shipworm — /ship werrm /, n. any of various wormlike marine bivalve mollusks that burrow into the timbers of ships, wharves, etc. [1770 80; SHIP + WORM] * * * or pileworm Any of approximately 65 species (family Teredidae) of common marine bivalves that can… …   Universalium

  • shipworm — noun Any of several wormlike marine mollusks, of the family Teredinidae, that bore through the wooden hulls of ships and other woody material entering the sea. Old spars and water soaked timbers cast on the beach are full of the workings of the… …   Wiktionary

  • shipworm — noun Date: circa 1778 any of various marine clams (especially family Teredinidae) that have a shell used for burrowing in submerged wood and a wormlike body and that cause damage to wharf piles and wooden ships …   New Collegiate Dictionary

  • shipworm — noun another term for teredo …   English new terms dictionary

  • shipworm — ship•worm [[t]ˈʃɪpˌwɜrm[/t]] n. ivt any of various wormlike marine bivalve mollusks of the family Teredinidae, that burrow into the timbers of ships, wharves, etc • Etymology: 1770–80 …   From formal English to slang

  • shipworm — /ˈʃɪpwɜm/ (say shipwerm) noun any of various marine bivalve molluscs which burrow into the timbers of ships, mangroves, submerged logs, etc …  

  • shipworm — n. = TEREDO …   Useful english dictionary

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