palolo worm

palolo worm
a polychaete worm, Eunice viridis, that lives in burrows among the coral reefs of several South Pacific islands, producing sperm or eggs in posterior segments that are cast off periodically in enormous numbers.
[1890-95]

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 any of various segmented marine worms of the families Eunicidae and Nereidae (class Polychaeta, phylum Annelida). The palolo worm exhibits unique breeding behaviour: during the breeding season, always at the same time of year and at a particular phase of the Moon, the worms break in half; the tail section (the “epitoke”), bearing reproductive cells, swims to the surface, where it releases eggs and sperm. Tens of thousands of epitokes swarm and release gametes simultaneously, attracting predatory fish and humans. The front section of the worm (the “atoke”) remains below in the substrate.

      Adults of the family Eunicidae are about 40 cm (16 inches) long and are divided into ringlike segments, each with paddlelike appendages bearing gills. Several sensory tentacles grow from the head. A pharynx that may be thrust forward is armed with teeth. Males of this family are reddish brown; females are bluish green.

      The palolo worm of the South Pacific (Palolo siciliensis [P. viridis or Eunice viridis]) inhabits crevices and cavities in coral reefs. As the breeding season approaches, the tail end of the body undergoes a radical change. The muscles and most of the organs degenerate, and the reproductive organs rapidly increase in size. The limbs on the posterior segment become more paddlelike. After the animal backs part way out of its tubelike burrow, the posterior section breaks free and swims to the surface as a separate animal, complete with eyes. The anterior end, still attached to its tube, regenerates a new posterior end.

      The free-swimming section always makes its appearance in the early morning for two days during the last quarter of the Moon in October. Twenty-eight days later, it appears in even greater numbers in the final quarter of the November Moon. At the surface of the sea the sperm and eggs are discharged, and fertilization occurs. Palolo tails, considered a delicacy by the Polynesians, are gathered in vast numbers during swarming.

      Widely distributed in the rock coral of the West Indies is the Atlantic palolo (E. furcata, or E. schemocephala), which swarms during the last quarter of the June–July Moon. The Japanese palolo (Tylorrhynchus heterochaetus), also considered a food delicacy, lives in the coastal waters of Japan.

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Universalium. 2010.

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Look at other dictionaries:

  • Palolo worm — Palolo Pa*lo lo, n., or Palolo worm Palolo worm . [From native name.] (Zo[ o]l.) A polystome worm ({Palolo viridis}) that burrows in the coral reefs of certain of the Pacific Islands. A little before the last quarter of the moon in October and… …   The Collaborative International Dictionary of English

  • Palolo worm — Taxobox image caption = image width = 250px status = DD | status system = IUCN2.3 regnum = Animalia phylum = Annelida classis = Polychaeta ordo = Eunicida familia = Eunicidae genus = Palola species = P. viridis binomial = Palola viridis binomial… …   Wikipedia

  • palolo worm — /pəˈloʊloʊ wɜm/ (say puh lohloh werm) noun a marine, polychaete, annelid worm of the southern Pacific, Leodice viridis, remarkable for the constancy with which it breeds, breaking off the posterior part of the body in the process, on the day of… …  

  • palolo worm — noun see palolo …   Useful english dictionary

  • Palolo — Pa*lo lo, n., or Palolo worm Palolo worm . [From native name.] (Zo[ o]l.) A polystome worm ({Palolo viridis}) that burrows in the coral reefs of certain of the Pacific Islands. A little before the last quarter of the moon in October and November …   The Collaborative International Dictionary of English

  • Palolo viridis — Palolo Pa*lo lo, n., or Palolo worm Palolo worm . [From native name.] (Zo[ o]l.) A polystome worm ({Palolo viridis}) that burrows in the coral reefs of certain of the Pacific Islands. A little before the last quarter of the moon in October and… …   The Collaborative International Dictionary of English

  • palolo — /peuh loh loh/, n., pl. palolos. See palolo worm. [1890 95; < Samoan or Tongan] * * * …   Universalium

  • Ver palolo — Varanus varius …   Wikipédia en Français

  • palola — Palolo Pa*lo lo, n., or Palolo worm Palolo worm . [From native name.] (Zo[ o]l.) A polystome worm ({Palolo viridis}) that burrows in the coral reefs of certain of the Pacific Islands. A little before the last quarter of the moon in October and… …   The Collaborative International Dictionary of English

  • Palola viridis — Palolo Pa*lo lo, n., or Palolo worm Palolo worm . [From native name.] (Zo[ o]l.) A polystome worm ({Palolo viridis}) that burrows in the coral reefs of certain of the Pacific Islands. A little before the last quarter of the moon in October and… …   The Collaborative International Dictionary of English

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