|
}}
'''''Riftia pachyptila''''' é unha especie de verme [[anélido]] xigante mariño<ref>{{cite book |title=Invertebrate Zoology: A functional Evolutionary Approach |edition=7th |last=Ruppert |first=E. |authorlink= |author2=Fox, R. |author3=Barnes, R. |year=2007 |publisher=Thomson Learning |location=Belmont |isbn=0-03-025982-7 |pages= }}</ref> (anteriormente clasificado nos [[filo (bioloxía)|filos]] [[Siboglinidae|Pogonophora]] e [[Vestimentifera]]) relacionado con outros vemes tubícolas que se encontran en [[zona peláxica|zonas peláxicas]] e intermareais. ''Riftia pachyptila'' vive desde uns 1 600 m de aprofundidadeprofundidade a varios miles de m, sobre o fondo do [[océano Pacífico]] preto das [[cheminea negra|chemineas negras]] e pode tolerar niveis de [[sulfuro de hidróxeno]] extremadamente altos. Estes vermes poden alcanzar a lonxitude de 2,4 m e os ses corpos tubulares teñen un diámetro de 4 cm. A temperatura ambiental no seu medio natural está entre os 2 e os 30º C.<ref name=Bright2008>{{cite journal | last = Bright | first = M. | author2 = Lallier, F. H. | title = The biology of vestimentiferan tubeworms | journal = Oceanography and Marine Biology: An Annual Review | volume = 48 | pages = 213–266 | publisher = [[Taylor & Francis]] | year = 2010 | url = http://www.sb-roscoff.fr/Ecchis/pdf/10-Bright-OMBAR.pdf | accessdate = 2013-10-30 | doi = 10.1201/ebk1439821169-c4 | deadurl = yes | archiveurl = https://web.archive.org/web/20131031234950/http://www.sb-roscoff.fr/Ecchis/pdf/10-Bright-OMBAR.pdf | archivedate = 2013-10-31 | df = }}</ref>
Non se debe confundir co molusco [[bivalvo]] ''[[Kuphus]]''.
== Desenvolvemento ==
''Riftia'' develop fromdesenvólvese a free-swimming,partir dunha larva [[pelagictrocófora]], peláxica nadadora e non-symbiotic [[trochophoresimbiose|simbiótica]] larva, whichque entersentra juvenileno desenvolvemento xuvenil ([[metatrochophoremetatrocófora]]) development, becomingconverténdose en [[sessility (zoology)|sessilesésil]] ande subsequentlyadquire acquiring symbioticseguidamente [[bacteria]]s simbióticas.<ref name=Bright>{{cite web|url=http://www.hydrothermalvent.com/php/index.php?option=com_content&view=article&id=46:riftia-pachyptila&catid=12:symbiosis&Itemid=19|title=Riftia pachyptila|author=Monica Bright}}</ref><ref>{{cite web|url=http://darchive.mblwhoilibrary.org/bitstream/handle/1912/5160/25-1_adams.pdf?sequence=1&isAllowed=y|title=Larval dispersal: Vent life in the ocean column|publisher=Oceanography|date=Mar 2012|author=Diane K. Adams|display-authors=etal}}</ref> As Thebacterias symbiotic bacteriasimbióticas, ondas whichcales adultos wormsvermes dependadultos fordependen sustenance,para areo notseu presentsustento, innon theestán gametespresentes nos [[gameto]]s, butsenón areque acquiredson fromincorporadas thedo environmentambiente viaa thetravés skinda inpel anun processproceso akinparecido toa anunha infection[[infección]]. TheO digestivetracto tractdixestivo transientlyconecta connects fromtransitoriamente a mouthboca, atsituada theno tipextremo ofdo theproceso medio ventral, mediala processun tointestino a foregutanterior, midgut,medio hindgute andposterior anuse ando wasano previouslye thoughtpensábase topreviamente haveque beenera theo methodcamiño bypolo whichque these bacteriaintroducían isas introducedbacterias intono adultscorpo dos adultos. Despois Afterde symbiontsque arese establishedestablecen inos thesimbiontes no intestino midgutmedio, itsofre undergoesunha substantialremodelación remodellingsubstancial ande enlargementun toagrandamento becomedo the trophosometrofosoma, whilementres theque remaindero ofresto thedo digestivetracto tractdixestivo hasxa notnon beense detecteddetecta innos adultespécimes specimensadultos.<ref>{{cite web|url=http://www.biolbull.org/content/177/2/254.full.pdf|title=On the early development of the vestimentiferan tube worm ''Ridgeia'' sp. and Observations on the Nervous System and Trophosome of ''Ridgeia'' sp. and ''Riftia pachyptila''|journal=Biol Bull|volume=177|pages=254–276|date=Oct 1989|author1=Meredith L. Jones |author2=Stephen L. Gardiner }}</ref>
== Estrutura corporal ==
[[FileFicheiro:Nur04507.jpg|thumbminiatura|300px|leftesquerda|Os vermes tubícolas de [[HydrothermalCheminea venthidrotermal|chemineas hidrotermais]] tubeworms getobteñen organiccompostos compoundsorgánicos fromdas bacteriabactrerias thatque liveviven inno theirseu trophosometrofosoma.]]
They have a highly [[wiktionary:vascular|vascularized]], red "plume" at the tip of their free end which is an organ for exchanging compounds with the environment (e.g., [[hydrogen sulfide|H<sub>2</sub>S]], [[carbon dioxide|CO<sub>2</sub>]], [[oxygen|O<sub>2</sub>]], etc.). The tube worm does not have many [[predator]]s. If threatened, the plume may be retracted into the worm's protective tube. The plume provides essential nutrients to [[bacteria]] living inside the [[trophosome]]. Tube worms have no digestive tract, but the bacteria (which may make up half of a worm's body weight) convert [[oxygen]], [[hydrogen sulfide]], [[carbon dioxide]], etc. into organic molecules on which their host worms feed. This process, known as [[chemosynthesis]], was recognized within the trophosome by [[Colleen Cavanaugh]].<ref name="Cavanaugh1981">{{cite journal | last = Cavanaugh | first = Colleen M. | authorlink = | title = Prokaryotic Cells in the Hydrothermal Vent Tube Worm ''Riftia pachyptila'' Jones: Possible Chemoautotrophic Symbionts | journal = Science | volume = 213 | issue = 4505 | pages = 340–342 | year = 1981 | doi = 10.1126/science.213.4505.340 | pmid = 17819907 | display-authors = 1 | last2 = Gardiner | first2 = S. L. | last3 = Jones | first3 = M. L. | last4 = Jannasch | first4 = H. W. | last5 = Waterbury | first5 = J. B. }}</ref>
|
