Spinochordodes tellinii

Taxobox | name = "Spinochordodes tellinii"

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image_width = 250px
image_caption = "Spinochordodes tellinii" with its bush-cricket host ("Meconema thalassinum")
regnum = Animalia
phylum = Nematomorpha
classis = Gordioidea
familia = Chordodidae
genus = "Spinochordodes"
species = "S. tellinii"
binomial = "Spinochordodes tellinii"
binomial_authority = (Camerano, 1888) [ITIS|ID=700110|taxon="Spinochordodes tellinii"]

The nematomorph hairworm "Spinochordodes tellinii" is a parasitic worm whose larvae develop in Orthopteran insects (grasshoppers and crickets). This parasite is able to influence its host's behavior: once the parasite is grown, it causes its grasshopper host to jump into water, where the grasshopper will likely drown. The parasite then leaves its host; the adult worm lives and reproduces in water. [ [http://www.newscientist.com/article.ns?id=dn7927 Parasites brainwash grasshoppers into death dive] , "New Scientist News", 31 August 2005] That "S. tellinii" influences its host to actively seek water is not presently supported. [cite journal|title=Do hairworms (Nematomorpha) manipulate the water seeking behaviour of their terrestrial hosts?|last=Thomas|first=F.|coauthors=SCHMIDT-RHAESA, A.; MARTIN, G.; MANU, C. ; DURAND, P. ; RENAUD, F. |date=May 2002|journal=Journal of Evolutionary Biology|publisher=Blackwell Science Ltd. |volume=16|issue=3|pages=356–361|url=http://pt.wkhealth.com/pt/re/jevb/abstract.00009809-200205000-00003.htm;jsessionid=LczVtnvJHr2JnzW0QLLv9hSncllDpvqqqySJYJ2vqhvkj27nQyGN!1177656273!181195629!8091!-1]

The microscopic larvae are ingested by their insect hosts and develop inside them into worms that can be three to four times longer than the host.

The precise molecular mechanism underlying the modification of the host's behaviour is not yet known. A study in 2005 indicated that grasshoppers which contain the parasite express, or create, different proteins in their brains than do uninfected grasshoppers. Some of these proteins have been linked to neurotransmitter activity, others to geotactic activity, or the body's response to changes in gravity. Further, it appeared that the parasite produces proteins from the Wnt family that act directly on the development of the central nervous system and are similar to proteins known from other insects, suggesting an instance of molecular mimicry. [cite journal |quotes=no |journal = Proceedings of the Royal Society B: Biological Sciences | volume = 272 |issue = 1577 |year=2005 |pages = 2117–2126 | url=http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1559948|doi=10.1098/rspb.2005.3213 |title = Behavioural manipulation in a grasshopper harbouring hairworm: a proteomics approach |author=Biron, D. G., L. Marché, F. Ponton, H. D. Loxdale, N. Galéotti, L. Renault, C. Joly & F. Thomas |pmid = 16191624]

A similar parasitic worm is "Paragordius tricuspidatus". [Andreas Schmidt-Rhaesa, David G. Biron, Cécile Joly and Frédéric Thomas. "Host–parasite relations and seasonal occurrence of Paragordius tricuspidatus and Spinochordodes tellinii (Nematomorpha) in Southern France", "Zoologischer Anzeiger - A Journal of Comparative Zoology", Volume 244, Issue 1, 15 August 2005, Pages 51-57]

References

External links

* [http://video.google.com/videoplay?docid=7226661303929118618 Video of "Spinochordodes tellinii"] , in which it causes a cricket to drown and then emerges from it