Chondrocladia

Chondrocladia Temporal range: Pleistocene? to Present
Scientific classification
Kingdom:	Animalia
Phylum:	Porifera
Class:	Demospongiae
Subclass:	Ceractinomorpha
Order:	Poecilosclerida
Suborder:	Mycalina
Family:	Cladorhizidae
Genus:	Chondrocladia Thomson, 1873
Species
33, but see text
Synonyms
Crinorhiza Schmidt, 1880 Meliiderma Ridley & Dendy, 1887

Chondrocladia is a genus of carnivorous demosponges of the family Cladorhizidae of mycalinan Poecilosclerida^[1]. Neocladia was long considered a junior synonym, but has recently become accepted as a distinct genus^[2].

33 named species are placed in this genus at present, but at least two additional undescribed ones are known to exist, while some of the described ones are known only from a few specimens or (e.g. the enigmatic Chondrocladia occulta) just a single one, and their validity and/or placement in Chondrocladia is doubtful. Chondrocladia sponges are stipitate, with a stalk frequently anchored in the substrate by rhizoids and an egg-shaped body, sometimes with branches that end in inflatable spheres.^[3]

Fossils assignable to this genus are known since the Pleistocene^[4], less than 2 million years ago. But given its deep sea habitat, Chondrocladia may well have been around for much longer – perhaps since the Mesozoic, as characteristic spicules (termed "microcricorhabds" or "trochirhabds"), almost identical to those of some living Chondrocladia, are known from Early Jurassic rocks almost 200 million years old^[5].

Carnivory

These sponges gained media attention when a new species, a gourd-shaped carnivorous sponge, was featured in reports of finds off the coast of Antarctica. The new Chondrocladia was one of 76^{[citation needed]} sponge species identified in the seas off Antarctica by the Antarctic Benthic Deep-Sea Biodiversity Project (ANDEEP) between 2002 and 2005, conducted aboard the German research vessel Polarstern.^[6]

Carnivorous sponges, which use hooked spicules to capture small crustaceans, have been known only since 1995, when Asbestopluma hypogea, another genus of the family Cladorhizidae, was identified in Mediterranean sea caves offshore La Ciotat (France)^[7]. Carnivory has since turned out to be common and typical for this sponge family^[8]. Unlike their relatives, Chondrocladia still possesses the water flow system and choanocytes typical of sponges, albeit highly modified to inflate balloon-like structures that are used for capturing prey^[9].

Species

The known species of Chondrocladia are:^[10]

Chondrocladia albatrossi Tendal, 1973 Chondrocladia amphactis (Schmidt, 1880) Chondrocladia antarctica Hentschel, 1914 Chondrocladia arctica (Hansen, 1885) Chondrocladia arenifera Brøndsted, 1929 Chondrocladia asigmata Lévi, 1964 Chondrocladia burtoni Tendal, 1973 Chondrocladia clavata Ridley & Dendy, 1886 Chondrocladia concrescens (Schmidt, 1880) Chondrocladia crinita Ridley & Dendy, 1886 Chondrocladia dichotoma Lévi, 1964 Chondrocladia fatimae Boury-Esnault & Van Beveren, 1982 Chondrocladia gigantea (Hansen, 1885) Chondrocladia gracilis Lévi, 1964 Chondrocladia guiteli Topsent, 1904 Chondrocladia koltuni Vacelet, 2006 Chondrocladia lampadiglobus Vacelet, 2006 – Ping-pong Tree Sponge

Chondrocladia levii Cristobo, Urgorri & Ríos, 2005 Chondrocladia magna Tanita, 1965 Chondrocladia michaelsarsii Arnesen, 1920 Chondrocladia multichela Lévi, 1964 Chondrocladia nani Boury-Esnault & Van Beveren, 1982 Chondrocladia nicolae Cristobo, Urgorri & Ríos, 2005 Chondrocladia nucleus (Hansen, 1885) Chondrocladia occulta Chondrocladia pulvinata Lévi, 1964 Chondrocladia scolionema Lévi, 1964 Chondrocladia stipitata Ridley & Dendy, 1886 Chondrocladia vaceleti Cristobo, Urgorri & Ríos, 2005 Chondrocladia verticillata Topsent, 1920 Chondrocladia virgata Thomson, 1873 (type species) Chondrocladia yatsui Topsent, 1930 Chondrocladia sp. 1 (Australia)[5] Chondrocladia sp. 2 (New Zealand)[5]

C. alaskensis and C. pulchra are better placed in Crambe^[11] or Monanchora^[1].

C. dura, C. ramosa and C. sessilis are junior synonyms of Iotrochota purpurea.^[1]

C. flabelliformis is now in Neocladia.^[12]

Footnotes

1. ^ ^{a b c} van Soest (2008)
2. ^ Vacelet (2008)
3. ^ Cristobo et al. (2005), Vacelet & Kelly (2008)
4. ^ Sepkoski (2002): p.560
5. ^ ^{a b c} Vacelet & Kelly (2008)
6. ^ Brandt et al. (2007), Scales (2007)
7. ^ Vacelet & Boury-Esnault (1995)
8. ^ Watling (2007), Vacelet (2008)
9. ^ Vacelet (2008), Vacelet & Kelly (2008)
10. ^ Vacelet & Kelly (2008), van Soest (2008)
11. ^ Cristobo et al. (2005)
12. ^ Vacelet (2008), van Soest (2008)

References

• Brandt, Angelika; Gooday, Andrew J.; Brandão, Simone N.; Brix, Saskia; Brökeland, Wiebke; Cedhagen, Tomas; Choudhury, Madhumita; Cornelius, Nils; Danis, Bruno; De Mesel, Ilse; Diaz, Robert J.; Gillan, David C.; Ebbe, Brigitte; Howe, John A.; Janussen, Dorte; Kaiser, Stefanie; Linse, Katrin; Malyutina, Marina; Pawlowski, Jan; Raupach, Michael & Vanreusel, Ann: First insights into the biodiversity and biogeography of the Southern Ocean deep sea. Nature 447(7142): 307-311. doi:10.1038/nature05827 (HTML abstract)
• Cristobo, Francisco Javier; Urgorri, Victoriano & Ríos, Pilar (2005): Three new species of carnivorous deep-sea sponges from the DIVA-1 expedition in the Angola Basin (South Atlantic). Organisms, Diversity & Evolution 5(Supplement 1): 203-213. doi:10.1016/j.ode.2004.11.004 (HTML fulltext)
• Scales, Helen (2007): Bizarre new deep-sea creatures found off Antarctica. National Geographic News, version of 2007-MAY-16. Retrieved 2007-MAY-17.
• Sepkoski, J. John Jr. (2002): A compendium of fossil marine animal genera. Bull. Am. Paleontol. 364: 1-563.
• Vacelet, Jean (2008): A new genus of carnivorous sponges (Porifera: Poecilosclerida, Cladorhizidae) from the deep N-E Pacific, and remarks on the genus Neocladia. Zootaxa 1752: 57–65. PDF abstract
• Vacelet, Jean & Boury-Esnault, N. (1995): Carnivorous sponges. Nature 373(6512): 333-335. doi:10.1038/373333a0 (HTML abstract)
• Vacelet, Jean & Kelly, Michelle (2008): New species from the deep Pacific suggest that carnivorous sponges date back to the Early Jurassic. Nat. Preced., posted 2008-SEP-25. doi:10101/npre.2008.2327.1 PDF fulltext
• van Soest, Rob (2008): Chondrocladia Thomson, 1873. In: Van Soest, R.W.M; Boury-Esnault, N.; Hooper, J.N.A.; Rützler, K.; de Voogd, N.J.; Alvarez, B.; Hajdu, E.; Pisera, A.B.; Vacelet, Jean; Manconi, R.; Schoenberg, C.; Janussen, D.; Tabachnick, K.R. & Klautau, M. (eds.): World Porifera database. Retrieved 2008-DEC-18.
• Watling, Les (2007): Predation on copepods by an Alaskan cladorhizid sponge. Journal of the Marine Biological Association of the UK 87(6): 1721-1726. doi:10.1017/S0025315407058560 (HTML abstract)

External links

• Photo of Chondrocladia lampadiglobus, the Ping-pong Tree Sponge, from The Deep by Claire Nouvian