[spahy-nee-hed-id] 
| any of a small group of endoparasites of the phylum Acanthocephala, as larvae parasitic in insects and crustaceans and as adults in various vertebrates. |
| spin·y-head·ed worm (spī'nē-hěd'ĭd) n. Any of various worms of the phylum Acanthocephala that live parasitically in the intestines of vertebrates and are characterized by a cylindrical, retractile proboscis that bears many rows of hooked spines. Also called acanthocephalan. |
spiny-headed worm spin·y-head·ed worm (spī'nē-hěd'ĭd)
n.
See Acanthocephala.
| spiny-headed worm (spī'nē-hěd'ĭd) Pronunciation Key
See acanthocephalan. |
spiny-headed worm
any animal of the invertebrate phylum Acanthocephala. A proboscis, or snout, which bears hooks, gives the group its name. There are about 600 recorded species, all of which are parasites in vertebrates (usually fish) as adults and in arthropods as juveniles. The adults are usually less than 1 cm (0.4 inch) in length, but some reach 50 cm (about 20 inches) or more. Spiny-headed worms are found throughout the world
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