Hexactinellida

Vertical view (left) and close-up of fossil holotype of Larispongia magdalenae, from Carrera (1998).

Belongs within: Animalia.

The Hexactinellida, glass sponges, are a group of sponges with a skeleton composed of silica, around with the (relatively sparse) cellular material is mostly conjoined into a multinucleate syncytium.

Characters (from Adl et al. 2012): Siliceous spicules triaxonic, hexactinic; cells forming extensive multinucleate syncytium, with some differentiated cells; electrical conductance across body; noncontractile body; larvae (poorly known) with medial region of ciliated cells.

<==Hexactinellida [Triaxonia]
    |--Hunanospongia EL11
    `--+--Pelicaspongiidae C98 [Amphidiscophora EL11, Amphidiscosa]
       |    |--Larispongia Carrera 1998 C98
       |    |    `--*L. magdalenae Carrera 1998 C98
       |    |--Pelicaspongia C98
       |    |--Twenhofelella C98
       |    |--Vaurealispongia C98
       |    |--Walliospongia C98
       |    |--Liscombispongia C98
       |    |--Warrembaia C98
       |    `--Kalimnospongia C98
       `--Hexasterophora EL11
            |--Calcihexactina EL11
            `--Protospongia EL11

Hexactinellida incertae sedis:
  Oopsacas minuta C-SC03
  Rhabdocalyptus dawsoni C-SC03
  Semperella schulzei F79
  Brabbinithes churkini Allison 1975 G79
  Hyalonema [Hyalonematidae] F79
    |--H. conus H04
    |--H. hozawai F79
    |--H. indicum H04
    |--H. molle Schulze 1904 BJ06
    |--H. populiferum PP15
    |--H. proximum Schulze 1904 BJ06
    |--H. simile Schulze 1904 BJ06
    `--H. valdiviae Schulze 1904 BJ06
  Farrea haeckelii H04
  Euplectellidae BJ06
    |--Holascus pseudostellatus Janussen, Tabachnick & Tendal 2004 BJ06
    `--Euplectella aspergillum H04
  Holtenia crateromorpha H04
  Sclerothamnus spiralis H04
  Polyopogon amadu H04
  Pheronematidae BJ06
    |--*Platylistrum platessa Schulze 1904 BJ06
    `--Pheronema rhaphanus H04
  Saccocalyx pedunculata H04
  Crateromorpha meyeri H04
  Hyaloslylus dives H04
  Polylophus philippinensis H04
  Stylocalyx tenera H04
  Monorhaphis [Monorhaphididae] AS12
    `--*M. chuni Schulze 1904 [incl. M. dives Schulze 1904] BJ06
  Lophocalyx AS12
  Heterochone calyx PP15
  Aphrocallistes vastus PP15
  Sympagella nux PP15
  Rossella fibulata PP15

*Type species of generic name indicated

REFERENCES

[AS12] Adl, S. M., A. G. B. Simpson, C. E. Lane, J. Lukeš, D. Bass, S. S. Bowser, M. W. Brown, F. Burki, M. Dunthorn, V. Hampl, A. Heiss, M. Hoppenrath, E. Lara, E. Le Gall, D. H. Lynn, H. McManus, E. A. D. Mitchell, S. E. Mozley-Stanridge, L. W. Parfrey, J. Pawlowski, S. Rueckert, L. Shadwick, C. L. Schoch, A. Smirnov & F. W. Spiegel. 2012. The revised classification of eukaryotes. Journal of Eukaryotic Microbiology 59 (5): 429–493.

[BJ06] Barnich, R., & D. Janussen. 2006. Die Typen und Typoide des Naturmuseums Senckenberg, Nr. 86. Type catalogue of the Porifera in the collections of the Senckenberg Museum in Frankfurt am Main, Germany. Senckenbergiana Biologica 86 (2): 127–144.

[C98] Carrera, M. G. 1998. First Ordovician sponge from the Puna region, northwestern Argentina. Ameghiniana 35: 205–210.

[C-SC03] Cavalier-Smith, T., & E. E.-Y. Chao. 2003. Phylogeny of Choanozoa, Apusozoa, and other Protozoa and early eukaryote megaevolution. Journal of Molecular Evolution 56: 540–563.

[EL11] Erwin, D. H., M. Laflamme, S. M. Tweedt, E. A. Sperling, D. Pisani & K. J. Peterson. 2011. The Cambrian conundrum: early divergence and later ecological success in the early history of animals. Science 334: 1091–1097.

[F79] Fry, W. G. 1979. Taxonomy, the individual and the sponge. In: Larwood, G., & B. R. Rosen (eds) Biology and Systematics of Colonial Organisms pp. 49–80. Academic Press: London.

[G79] Glaessner, M. F. 1979. Precambrian. In: Robison, R. A., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt A. Introduction. Fossilisation (Taphonomy), Biogeography and Biostratigraphy pp. A79–A118. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

[H04] Haeckel, E. 1899–1904. Kunstformen der Natur. Bibliographisches Institut: Leipzig und Wien.

[PP15] Pisani, D., W. Pett, M. Dohrmann, R. Feuda, O. Rota-Stabelli, H. Philippe, N. Lartillot & G. Wörheide. 2015. Genomic data do not support comb jellies as the sister group to all other animals. Proceedings of the National Academy of Sciences of the USA 112 (50): 15402–15407.