Thirty-three 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 enigmaticChondrocladia occulta) just a single one, and their validity and/or placement inChondrocladia is doubtful.Chondrocladia sponges arestipitate, with a stalk frequently anchored in the substrate byrhizoids and an egg-shaped body, sometimes with branches that end in inflatable spheres.[5][6]
Fossils assignable to this genus are known since thePleistocene,[7] less than two million years ago. However, given itsdeep seahabitat,Chondrocladia may well have been around for much longer – it existed perhaps as early as theMesozoic Era, as characteristicspicules (termed "microcricorhabds" or "trochirhabds"), almost identical to those of some livingChondrocladia, are known fromEarly Jurassic rocks almost two hundred million years old.[6]
These sponges gained media attention when a newspecies, a gourd-shaped carnivorous sponge, was featured in reports of finds off the coast of Antarctica. The newChondrocladia was one of seventy-six[citation needed] sponge species identified in the seas off Antarctica by theAntarctic Benthic Deep-Sea Biodiversity Project (ANDEEP) between 2002 and 2005, conducted aboard the German research vesselPolarstern.[8][9]
Carnivorous sponges, which use hooked spicules to capture smallcrustaceans, have been known only since 1995, whenAsbestopluma hypogea, another genus of the family Cladorhizidae, was identified inMediterranean sea caves offshoreLa Ciotat (France) byJean Vacelet andNicole Boury-Esnault.[10] Carnivory has since turned out to be common and typical for this sponge family.[11][4] Unlike their relatives,Chondrocladia still possesses the water flow system andchoanocytes typical of sponges, albeit highly modified to inflate balloon-like structures that are used for capturing prey.[4][6]
^* Vacelet, J. (2006). New carnivorous sponges (Porifera, Poecilosclerida) collected from crewed submersibles in the deep Pacific.Zoological Journal of the Linnean Society148: 553–584. Figure 17.doi:10.1111/j.1096-3642.2006.00234.x
^Van Soest, R. W. M., Boury-Esnault, N., Vacelet, J., Dohrmann, M., Erpenbeck, D., De Voogd, N. J., Santodomingo, N., Vanhoorne, B.,Kelly, M., Hooper, J. N. A. (2011). Global Diversity of Sponges (Porifera).PLoS ONE7(4): e35105.Figure 3.doi:10.1371/journal.pone.0035105
^abcdevan Soest, R. (2014). Van Soest RW, Boury-Esnault N, Hooper JN, Rützler K, de Voogd NJ, de Glasby BA, Hajdu E, Pisera AB, Manconi R, Schoenberg C, Janussen D, Tabachnick KR, Klautau M, Picton B, Kelly M, Vacelet J (eds.)."Chondrocladia Thomson, 1873".World Porifera Database.World Register of Marine Species. Retrieved2014-04-30.
^abCristobo, 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.
^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 (17 May 2007). "First insights into the biodiversity and biogeography of the Southern Ocean deep sea".Nature.447 (7142):307–311.Bibcode:2007Natur.447..307B.doi:10.1038/nature05827.PMID17507981.S2CID4414557.
