Sunday, May 1, 2011

The Tongue Worm

Tongue Worms
By: Demi DeRose

Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Crustacea
Class: Maxillopoda
Subclass: Linguatulida
In Greek the scientific name Pentastomida means: pente = five; stoma = mouth. This name is derived from the fact that at the top of the cephalothorax the tongue worm has 5 legs. Four of the legs are hooklike, and the fifth is a jawless mouth that is used mainly used for sucking blood and internal tissues. Tongue worms are land living and usually take the host of reptiles, but also birds, and mammals.

· Length ranges from2-13 centimeters
· Anterior end of body has 5 legs: 4 clawed legs, 1bears the mouth (jawless)
· Body covered in a chitinous cuticle
· Simple digestive system (tubular); they feed entirely of blood so the mouth is like a muscular pump
· Nervous system: includes a ventral nerve cord with ganglia; the body contains a haemocoel but there is no circulatory, respiratory, or excretory system
· Hydrostatic skeleton

Form& Function:
The tongue worms usual host is in the lungs of basically any sort of reptile, where they absorb their blood tissue and fluids. As far as reproduction is concerned, fertilization is internal and the sexes of tongue worms are separate, and the female is able to produce millions of eggs. The eggs are then swallowed by the host, and are excreted as larvae with the hosts’ feces.
The tongue worms move by circular and longitudinal muscles. On the cephalothorax, the worms have 2 pair of hook like retractable claws. There are five known species of tongue worms that can infect humans with a disease called visceral pentastomiasis; when humans become infected it is usually accidental and is most noticeably found is patients that consumed undercooked snake meat.
Tongue worms are an extremely plentiful species which is neither endangered nor threatened. They have no known predators.

Impact on the World/Humanity:
The main impact that tongue worms have on our world is when they infect humans. When they are in the digestive tract of the human, tiny four legged larvae hatch and invade the visceral mass. But according to a study in 2009 no prescription medicine was needed to treat the disease because the parasites would eventually degenerate within two years.
Journal Article Review:
The tongue worms must complete their life cycle in more than one single host. Larval hosts are called intermediate hosts (accidently swallows the eggs as they eat) and the hosts of adults are considered definitive hosts (the larvae break out of the cyst of another animal eats the intermediate host).

Work Cited:
PENTASTOMIDA, Linguatulida, tongue worms. (n.d.). Home Page. Retrieved May 1, 2011, from
Haemocoel - definition from (n.d.). Life Science Reference - Biology Online. Retrieved May 1, 2011, from
Pentastomida - Encyclopedia of Life. (n.d.). Encyclopedia of Life. Retrieved May 1, 2011, from
Pentastomida - Wikipedia, the free encyclopedia. (n.d.). Wikipedia, the free encyclopedia. Retrieved May 1, 2011, from
Tongue Worms: Pentastomida - Behavior And Reproduction - Host, Hosts, Eggs, Larvae, Definitive, and Intermediate . (n.d.). Animal Life Resource. Retrieved May 2, 2011, from

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