Chondrocladia
Encyclopedia
Chondrocladia is a genus
of carnivorous demosponges of the family
Cladorhizidae of mycalinan Poecilosclerida
. Neocladia was long considered a junior synonym, but has recently become accepted as a distinct genus.
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 rhizoid
s and an egg-shaped body, sometimes with branches that end in inflatable spheres.
Fossil
s assignable to this genus are known since the Pleistocene
, 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 spicule
s (termed "microcricorhabds" or "trochirhabds"), almost identical to those of some living Chondrocladia, are known from Early Jurassic
rocks almost 200 million years old.
, a gourd-shaped carnivorous sponge, was featured in reports of finds off the coast of Antarctica. The new Chondrocladia was one of 76 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.
Carnivorous sponges, which use hooked spicule
s to capture small crustacean
s, 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
). Carnivory has since turned out to be common and typical for this sponge family. Unlike their relatives, Chondrocladia still possesses the water flow system and choanocyte
s typical of sponges, albeit highly modified to inflate balloon-like structures that are used for capturing prey.
C. alaskensis and C. pulchra are better placed in Crambe or Monanchora.
C. dura, C. ramosa and C. sessilis are junior synonyms of Iotrochota purpurea.
C. flabelliformis is now in Neocladia.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of carnivorous demosponges of the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Cladorhizidae of mycalinan Poecilosclerida
Poecilosclerida
Poecilosclerida is an order of mostly marine demosponges though there are a few freshwater species. It is the most speciose of the orders and contains about 25 recognised families...
. Neocladia was long considered a junior synonym, but has recently become accepted as a distinct genus.
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 rhizoid
Rhizoid
Rhizoids are thread-like growths from the base or bottom of a plant, found mainly in lower groups such as algae, fungi, bryophytes and pteridophytes, that function like roots of higher plants ....
s and an egg-shaped body, sometimes with branches that end in inflatable spheres.
Fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
s assignable to this genus are known since the Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
, less than 2 million years ago. But given its deep sea
Deep sea
The deep sea, or deep layer, is the lowest layer in the ocean, existing below the thermocline and above the seabed, at a depth of 1000 fathoms or more. Little or no light penetrates this part of the ocean and most of the organisms that live there rely for subsistence on falling organic matter...
habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
, Chondrocladia may well have been around for much longer – perhaps since the Mesozoic
Mesozoic
The Mesozoic era is an interval of geological time from about 250 million years ago to about 65 million years ago. It is often referred to as the age of reptiles because reptiles, namely dinosaurs, were the dominant terrestrial and marine vertebrates of the time...
, as characteristic spicule
Spicule
Spicules are tiny spike-like structures of diverse origin and function found in many organisms, such as the copulatory spicules of certain nematodes or the grains on the skin of some frogs.In sponges, spicules perform a structural function....
s (termed "microcricorhabds" or "trochirhabds"), almost identical to those of some living Chondrocladia, are known from Early Jurassic
Early Jurassic
The Early Jurassic epoch is the earliest of three epochs of the Jurassic period...
rocks almost 200 million years old.
Carnivory
These sponges gained media attention when a new speciesSpecies
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
, a gourd-shaped carnivorous sponge, was featured in reports of finds off the coast of Antarctica. The new Chondrocladia was one of 76 sponge species identified in the seas off Antarctica by the Antarctic Benthic Deep-Sea Biodiversity Project
Antarctic Benthic Deep-Sea Biodiversity Project
The Antarctic Benthic Deep-Sea Biodiversity Project is an international project to investigate deep-water biology of the Scotia and Weddell seas. Benthic refers to "bottom-dwelling" organisms that are known to exhibit unusual characteristics not normally seen in shallow-dwelling creatures...
(ANDEEP) between 2002 and 2005, conducted aboard the German research vessel Polarstern.
Carnivorous sponges, which use hooked spicule
Spicule
Spicules are tiny spike-like structures of diverse origin and function found in many organisms, such as the copulatory spicules of certain nematodes or the grains on the skin of some frogs.In sponges, spicules perform a structural function....
s to capture small crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s, have been known only since 1995, when Asbestopluma hypogea, another genus of the family Cladorhizidae, was identified in Mediterranean sea caves offshore La Ciotat
La Ciotat
La Ciotat is a commune in the Bouches-du-Rhône department in the Provence-Alpes-Côte d'Azur region in southern France. It is part of the metropolitan area of Marseille Provence. La ciotat is located to the east of Marseille at an equal distance from Marseille and Toulon...
(France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
). Carnivory has since turned out to be common and typical for this sponge family. Unlike their relatives, Chondrocladia still possesses the water flow system and choanocyte
Choanocyte
Choanocytes are cells that line the interior of Asconoid, syconoid and leuconoid body type sponges that contain a central flagellum surrounded by a collar of microvilli which are connected by a thin membrane. It is the closest family member to the free-living ancestor called choanoflagellate...
s typical of sponges, albeit highly modified to inflate balloon-like structures that are used for capturing prey.
Species
The known species of Chondrocladia are:C. alaskensis and C. pulchra are better placed in Crambe or Monanchora.
C. dura, C. ramosa and C. sessilis are junior synonyms of Iotrochota purpurea.
C. flabelliformis is now in Neocladia.
External links
- Photo of Chondrocladia lampadiglobus, the Ping-pong Tree Sponge, from The Deep by Claire Nouvian
