Loricifera

Loricifera

Taxobox
name = Loricifera


image_width = 200px
image_caption = "Pliciloricus enigmatus"
regnum = Animalia
phylum = Loricifera
phylum_authority = Kristensen, 1983
subdivision_ranks = Genera
subdivision = "Nanaloricus" "Armorloricus" "Phoeniciloricus" "Pliciloricus" "Rugiloricus" "Spinoloricus" "Titaniloricus"

Loricifera (from Latin, "lorica", corselet + Greek, φορη, "phora", bearing) is a small phylum of marine sediment-dwelling animals with twenty-two described species, in eight genera.Gad, G. 2005. Successive reduction of the last instar larva of Loricifera, as evidenced by two new species of Pliciloricus from the Great Meteor Seamount (Atlantic Ocean). Zoologischer Anzeiger. 243: 239-271.] Ruppert, Edward E., Richard S. Fox, and Robert D. Barnes. Invertebrate Zoology. 7th ed. Toronto: Brooks/Cole - Thomson Learning, 2004. 776.] Aside from these described species, there are approximately 100 more which have been collected and not yet described. They are characterised by a protective outer case called a lorica and their habitat, which is in the spaces between marine gravel to which they attach themselves. The phylum was discovered in 1983 by Reinhardt Kristensen, in Roscoff, France.Heiner, I., Kristensen, R.H. 2005. Two new species of the genus Pliciloricus (Loricifera, Pliciloricidae) from the Faroe Bank, North Atlantic. Zoologischer Anzeiger. 243: 121-138.] They are among the very latest of discovered groups of Metazoans.Kristensen, R.M. 2002. An Introduction to Loricifera, Cycliophora, and Micrognathozoa. Integrative and Comparative Biology. 42: 641-651.] They attach themselves quite firmly to the substratum, and so remained undiscovered for so long. The first specimen was collected in the 1970s, and later described in 1983. They are found at all depths, in different sediment types, and in all latitudes.

The animals have a head, mouth and digestive system as well as a lorica. The armor-like lorica consists of a protective external shell or case of encircling plicae. There is no circulatory system and no endocrine system. Many of the larvae are acoelomate, with some adults being pseudocoelomate, and some remaining acoelomate. The animals are hermaphrodites and probably oviparous. They have a very complex life cycle. The species which live in the deep sea are able to reproduce via parthenogenetic or paedogenetic reproduction. They are not known to be present in the fossil record.

Their closest relatives are thought to be the Kinorhyncha and Priapulida with which they constitute the taxon Scalidophora. The three phyla share four characters in common – chitinous cuticle, rings of scalids on the introvert, flosculi, and two rings of introvert retracts. A group called Introverta is formed with Kinorhyncha, Priapulida, Nematoda, and Nematomorpha.

References


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  • Loricifera — es un escaso filo de animales marions que comprende unas doce especies. Fue descubierto en 1983 por Reinhardt Kristensen. Estos animales poseen cabeza, boca y tracto digestivo, amén de esqueleto de carcasas en escala para su desplazamiento.… …   Enciclopedia Universal

  • Loricifera — Loricifera, 1983 erstmals beschriebene marine Klasse der ⇒ Nemathelminthes; bis 400 μm groß; äußerlich durch ihr hakenbesetztes einstülpbares Vorderteil den ⇒ Kinorhyncha und ⇒ Priapulida ähnlich …   Deutsch wörterbuch der biologie

  • Loricifera — Loricifera …   Wikipédia en Français

  • Loricifera — Korsetttierchen Korsetttierchen Pliciloricus enigmatus Systematik Unterreich: Vielzellige Tiere (Metazoa) …   Deutsch Wikipedia

  • Loricifera —   Loricifera Pliciloricus enigmat …   Wikipedia Español

  • Loricifera — …   Википедия

  • loricifera — n. [L. lorica, corselet; fero, bear] A phylum of microscopic organisms with a flexible, retractable tube mouth, a girdle of platelets and a crown of clawlike and club shaped spines …   Dictionary of invertebrate zoology

  • Loricifera — …   Useful english dictionary

  • Lorica (Loricifera) — La lorica est, chez les Loricifera, l exosquelette composé de plaque durs qui recouvre l abdomen. La structure de cette cuirasse est utilisée pour la systématique du groupe. Ce nom vient du latin loricus corset. Portail de la zoologie …   Wikipédia en Français

  • Loricifère — Loricifera Loricifera …   Wikipédia en Français

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