| Rossella antarctica | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Porifera |
| Class: | Hexactinellida |
| Order: | Lyssacinosida |
| Family: | Rossellidae |
| Genus: | Rossella |
| Species: | R. antarctica |
| Binomial name | |
| Rossella antarctica Carter, 1872 | |
| Synonyms [1] | |
| |
Rossella antarctica is a relatively small species of glass sponge. It is widely distributed in the southern hemisphere, particularly in the Antarctic and sub-Antarctic regions.
This off-white to grey sponge may grow up to 300 mm (12 in) long. [2] It has a semispherical to ovoid form with a large, deep oscule on the upper surface. [2] [3] The upper part also has the largest diameter of the organism. [3] The body is dense and contains relatively few canals. [4] The whole surface is covered with long, hair like spicules that may protrude up to 30 mm (1.2 in) from the surface. [2] These spicules are most dense at the base, where they entangle to form a stalk that attaches the sponge to the substrate. [5]
The following spicules make up the skeleton of this species: [3] [5]
While this species is mostly known from the Antarctic, it has also been found off the coats of South Africa, Namibia, South America, and New Zealand. [2] [5] It has been found at depths of 8–2,000 m (26–6,562 ft). [2]
Along with Anoxycalyx joubini and Rossella nuda and Rossella racovitzae , Rossella antarctica is one of the main hexactinellid sponges that comprise the bulk of Antarctic benthic biomass. [6] Consequently, they form an important part of these communities. Individuals house a variety of invertebrate infauna, with an average of nearly 800 individuals per 100 ml. [4] These include species belonging to a variety of taxa, including foraminiferans, polychaetes, arthropods, amphipods, copepods, nematodes, and molluscs. At least 68 species have been found - more than in any of the other mentioned species. [4] This includes Halacarellus obsoletus , a mite that is believed to be an obligate associate of glass sponges. [7] While the chemical defenses against predation in glass sponges are poorly known, Rossella antarctica has been observed to contain a chemical compound that has been shown to act as a deterrent against Odontaster validus at the very least. [8]
This species has been observed to reproduce by budding. [6]
Sponges, the members of the phylum Porifera, are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through them, consisting of jelly-like mesohyl sandwiched between two thin layers of cells.
Hexactinellid sponges are sponges with a skeleton made of four- and/or six-pointed siliceous spicules, often referred to as glass sponges. They are usually classified along with other sponges in the phylum Porifera, but some researchers consider them sufficiently distinct to deserve their own phylum, Symplasma. Some experts believe glass sponges are the longest-lived animals on earth; these scientists tentatively estimate a maximum age of up to 15,000 years.
The Venus' flower basket is a glass sponge in the phylum Porifera. It is a marine sponge found in the deep waters of the Pacific ocean, usually at depths below 500 meters. Like other sponges, they feed by filtering sea water to capture plankton and marine snow. Similar to other glass sponges, they build their skeletons out of silica, which forms a unique lattice structure of spicules. The sponges are usually between 10 cm and 30 cm tall, and their bodies act as refuge for their mutualist shrimp partners. This body structure is of great interest in materials science as the optical and mechanical properties are in some ways superior to man-made materials. Little is known regarding their reproduction habits, however fluid dynamics of their body structure likely influence reproduction and it is hypothesized that they may be hermaphroditic.
Sponge reefs are reefs formed by Hexactinellid sponges, which have a skeleton made of silica, and are often referred to as glass sponges. Such reefs are now very rare, and found only in waters off the coast of British Columbia, Washington and southern Alaska. Recently sponge reefs were identified within the strait of Georgia and Howe sound close to Vancouver. Although common in the late Jurassic period, reef-building sponges were believed to have gone extinct during or shortly after the Cretaceous period, until the existing reefs were discovered Queen Charlotte sound in 1987–1988 – hence these sometimes being dubbed living fossils.
The cloud sponge(Aphrocallistes vastus) is a species of sea sponge in the class Hexactinellida. It is a deep-water reef-forming animal. The species was first described by F.E. Schulze in 1886.
Spicules are structural elements found in most sponges. The meshing of many spicules serves as the sponge's skeleton and thus it provides structural support and potentially defense against predators.
The orange wall sponge is a species of sea sponge belonging to the order Trachycladida. It is found in the south Atlantic and Indo-Pacific oceans. Around the South African coast, it is known from the Cape Peninsula to Cape Agulhas.
Cinachyra antarctica is a species of antarctic sponge belonging to the family Tetillidae. It was first described by H.J. Carter in 1872. A 2002 study in Antarctica calculated that this sponge and another antarctic sponge, Anoxycalyx joubini, have amazingly long lifespans surpassing 1,550 years in C. antarctica and 15,000 years in A. joubini. A. joubini lives in deeper waters than C. antarctica. Antarctic sponges have such lifespans, probably because of their surroundings, living at 100–2,000 m (330–6,560 ft) below the surface, at extremely cold temperature and constant pressure. This may slow down their growth rate and other biological processes, which has a remarkable lifespan as a result, because in a caught specimen of A. joubini did not show any growth in a span of 10 years. C. antarctica lives at the bottom, as a benthic, sessile creature. Complete specimens have large, visible pores and an overall yellowish appearance with hair-like structures covering some parts next to the pores, giving it the look of a giant virus. Caught specimens are usually incomplete and rarely measure more than 2.5–3 cm.
Rossellidae is a family of glass sponges belonging to the order Lyssacinosa. The family has a cosmopolitan distribution and is found at a large range of depths.
Sceptrulophora is an order of hexactinellid sponges, commonly known as Glass sponges, characterized by sceptrule spicules, that is, "microscleric monactinal triaxonic spicules that include clavules with terminel umbels or smooth heads." Species of the order Sceptrulophora have existed since the Jurassic period, and still flourish today. While there is ongoing debate about the organization of various taxa in Sceptrulophora, the monophyly of the taxon Sceptrulophora is supported by the presence of sceptrules in most of the extant species, and has recently been further supported by DNA sequencing.
Bolosoma is a genus of pedunculated siliceous sponges belonging to the family Euplectellidae. This genus lives in deep-sea environments and provides a habitat for a plethora of other benthic species, giving Bolosoma an incredibly important ecological role in the ecosystems it is a part of.
Diapleuridae is a family of five extinct species of marine glass sponges found in the Caribbean Sea, Florida Straits, Banda Sea, and US Virgin Islands. A sixth species–Diapleura hatoni–is postulated to have existed around the same time as the other five, but there is limited research on it. Diapleuridae is part of class Hexactinellida and order Lyssacinosida. These sponges lived during the Middle Epoch of the Eocene and were filter feeders that were attached to the benthos by a basal disc. The oldest recorded fossil of a species of Diapluridae is from 47.8 million years ago, with the most recent fossil dated 41.3 million years ago.
Hamacantha esperoides is a species of demosponge. It is commonly known as the fibrous sponge. It occurs off the southern and western coasts of South Africa, off the coast of Namibia, and off the southeast coast of South America.
Inflatella belli, or the gooseberry sponge, is a species of demosponge that appears to be restricted to the southern hemisphere, where it is widespread. It occurs from the coast of Namibia and the Indo-pacific, down to the Subantarctic and Antarctic regions.
Infantella is a genus of demosponges in the family Coelospharidae. The species in this genus differ from those in other genera through having a single kind of diactinal megascleres and no mircoscleres. This genus contains 6 species.
Suberites dandelenae, the amorphous solid sponge, is a species of deep-sea demosponge from South Africa and Namibia.
Penares sphaera, the crater sponge, is a deep sea demosponge from southern Africa.
Tetilla capillosa, the furry sponge, is a species of demosponge from southern Africa.
Rosella is a genus of glass sponges in the family Rossellidae. It is found in the Antarctic and sub-Antarctic regions.
Anoxycalyx joubini is a species of Antarctic sponge. The species may have an extremely long lifespan, with estimates of up to 15,000 years. A. joubini occurs in deeper waters than the similar species Cinachyra antarctica, which is also very long-lived. Antarctic sponges live at 100–2,000 m (330–6,560 ft) below the surface, in extremely cold temperatures and constant pressure. This may slow down their growth rate and other biological processes because one caught specimen of A. joubini, did not show any growth in a span of 10 years.