Calcarea

The Éponges limestones are organizations pertaining to the group of the Métazoaire S (animals) of very simple organization: They present only two cellular layers (Endoderme and Ectoderme), they are thus described as Diploblastique S.

Structure

The Squelette of these Sponges is exclusively made up of spicules Calcaire S, generally in the form of Calcite, forming a continuous mass sometimes. A difference with other “Sponges” is the absence of a differentiation of the spicules in microsclères and mégasclères . These two points constitute specific characteristics to this group.

The forms met do not go from simplest (type ascon ), with most complex comprising in addition to the vibratile baskets and the inhaling and exhaling channels (standard leucon ), while passing by the intermediate forms not having in any more but vibratile baskets (standard sycon ).

Habitat

The Éponges limestones are all marine. But, probably because of the composition of their skeleton, the majority of the species meet in the first 100 meters under surface. (See solubility of the Carbonate of calcium). However, certain species live with abyssal depths .

Ethology

These organizations need a hard substrate to develop. The Larve is fixed on a support by the end blastoporale.

Embryology

The Gastrulation was observed in the forms Sycon .

List Sponge limestones species among the 1000 known ones (alphabetically of the scientific name)

  • Chancellaria sp. (older Fossil known: -540 MY; Cambrien)
  • Grantia compressed
  • Leucandria will aspera
  • Leucosolenia complicata
  • Sycon elegans
  • Sycon raphanus

List orders

  • superorder Pharetronida Zittel, 1878
  • subclass Calcaronea Bidder, 1898
    • order Baerida Borojevic, Boury-Esnault and Vacelet, 2000
    • order Leucosolenida Hartmann, 1958
    • order Lithonida Vacelet, 1981
  • subclass Calcinea
    • order Clathrinida Hartmann, 1958
    • order Murrayonida Vacelet, 1981

Classify sponges limestones (Calcarea)

  • Under Class of Calcaronea
    • Order of Leucocoleniidés
      • Family: Amphoriscidés, Grantiidés, Hétéropiidés, Lepidoleuconidés
leucosoléniidés, staurorrhaphidés, sycettidés.

  • Under Class of Calcinea

    • Order of clathrinidés the
      • Family: clathrinidés, leucaltidés, leucastidés, leucettidés, paramurranyonidés, soleniscidés
    • Order of murrayonidés the
      • Family: lelapiellidés, myrrayonidés, paramurrayonidés

  • Order of Lithinidés

      • Family of lélapiidés, minchinellidés, pétrobionidés the

See too

With reading

phylogenetic Classification of alive the by Guillaume Lecointre and Herve Guyader with the editions Belin

External bonds

Random links:Fossa (exogeology) | Jacques d' Ibelin | Museo heráldico del estado | Tan studio | Veronica Hamel | Brother sleep | Comté_de_puissance,_Idaho