Lugworm

Lugworm

Taxobox | name = Lugworm



image_width = 240px
image_caption = Lugworm, "Arenicola marina", casts on the beach at Ballyholme, Northern Ireland
regnum = Animalia
phylum = Annelida
classis = Polychaeta
ordo = Capitellida
familia = Arenicolidae
genus = "Arenicola"
species = "A. marina"
binomial = "Arenicola marina"
binomial_authority = (Linnaeus, 1758)

The lugworm or sandworm is a large marine worm of the phylum Annelida. Its coiled castings are a familiar sight on a beach at low tide but the animal itself is not seen except by those who, from curiosity or to use as fishing bait, dig the worm out of the sand.

Overview

When fully grown, the lugworm of the coasts of Europe is up to 9 inches long and 3/8ths inch in diameter. Other species on the North American coast range from 3 to 12 inches. The body is like that of an earthworm: ringed or segmented. Its head end, which is blackish-red and bears no tentacles or bristles, passes into a fatter middle part which is red. This in turn passes into a thinner yellowish-red tail end. The middle part has bristles along its sides and also pairs of feathery gills. There is a well developed system of blood vessels with red blood rich in the oxygen-carrying pigment, haemoglobin.

Life in a burrow

A lugworm lives in a U-shaped burrow in sand. The U is made of an L-shaped gallery lined with mucus, from the toe of which a vertical unlined shaft runs up to the surface. This is a head shaft. At the surface the head shaft is marked by a small saucer-shaped depression. The tail shaft, 2-3 inches from it, is marked by a highly coiled cast of sand. The lugworm lies in this burrow with its head at the base of the head shaft, swallowing sand from time to time. This makes the column of sand drop slightly, so there is a periodic sinking of the sand in the saucer-shaped depression. When it first digs its burrow the lugworm softens the sand in its head up into the head shaft by pushing its head up into it with a piston action. After that it is kept loose by a current of water driven through the burrow from the hind end, by the waves of contraction passing along its body. It weighs 2-5 oz. Lugworms also have groups of hair on the outside of their bodies that act as external gills. This can rapidly increase its uptake of oxygen.

Burrowing babies

Once it burrows into the sand a lugworm seldom leaves it. It can stay there for weeks on end, sometimes changing its position slightly in the sand. But it may leave the burrow completely and re-enter the sand, making a fresh burrow for breeding but for 2 days in early October there is a genital crisis. This is when all the lugworms liberate their ova and sperms into the water above, and there the ova are fertilized. The ova are enclosed in tongue-shaped masses of jelly about 8 inches long, 3 inches wide and 1 inch thick. Each mass is anchored at one end. The larvae hatching from the eggs feed on the jelly and eventually break out when they have grown to a dozen segments and are beginning to look like their parents. They burrow into the sand, usually higher up the beach than the adults, and gradually move down the beach as they get older.

In popular culture

Cartoonist Piers Baker created a syndicated comic strip called "Ollie And Quentin", with a buddy storyline about Ollie, a seagull and Quentin, a lugworm. The strip originated in the UK in 2002 and went into international syndication in early 2008. Baker considers the strip "...an homage to all the poor lugworms that he used as bait while sea fishing in his youth."


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Look at other dictionaries:

  • lugworm — ► NOUN ▪ a bristle worm living in muddy sand and leaving characteristic worm casts, used as fishing bait. ORIGIN from earlier lug lugworm , of unknown origin …   English terms dictionary

  • Lugworm — Lug worm , n. [1st lug + worm.] (Zo[ o]l.) A large marine annelid ({Arenicola marina}) having a row of tufted gills along each side of the back. It is found burrowing in sandy beaches, both in America and Europe, and is used for bait by European… …   The Collaborative International Dictionary of English

  • lugworm — c.1600, from lug, probably a Celtic word (the first recorded use is in a Cornwall context) unrelated to lug (n.) or lug (v.) + WORM (Cf. worm). But OED suggests connection with lug (v.) on the notion of heavy, clumsy …   Etymology dictionary

  • lugworm — [lug′wʉrm΄] n. [ LUG3 + WORM] any of a family (Arenicolidae) of polychaetous worms that burrow into sandy seashores and are used for bait …   English World dictionary

  • lugworm — /lug werrm /, n. any burrowing annelid of the genus Arenicola, of ocean shores, having tufted gills: used as bait for fishing. Also called lug. [1795 1805; LUG4 + WORM] * * * ▪ polychaete genus       (genus Arenicola), any of several marine worms …   Universalium

  • lugworm — noun Etymology: origin unknown Date: 1802 any of a genus (Arenicola) of marine polychaete worms that have a row of tufted gills along each side of the back and are used for bait …   New Collegiate Dictionary

  • lugworm — noun A large marine worm of the phylum Annelida, whose coiled castings can often be seen on beaches at low tide. Syn: sandworm …   Wiktionary

  • lugworm — lug|worm [ˈlʌgwə:m US wə:rm] n BrE a small ↑worm that lives in sand by the sea, often used to catch fish …   Dictionary of contemporary English

  • lugworm — n. marine worm with short stiff hair used as fishing bait …   English contemporary dictionary

  • lugworm — noun a bristle worm living in muddy sand and leaving characteristic worm casts, widely used as fishing bait. [Arenicola marina.] Origin C19: from earlier lug (of unknown origin) + worm …   English new terms dictionary

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