Benthos, also known as benthon, is the community of organisms that live on, in, or near the bottom of a sea, river, lake, or stream, also known as the benthic zone. This community lives in or near marine or freshwater sedimentary environments, from tidal pools along the foreshore, out to the continental shelf, and then down to the abyssal depths.
Xenophyophorea is a clade of foraminiferans. Xenophyophores are multinucleate unicellular organisms found on the ocean floor throughout the world's oceans, at depths of 500 to 10,600 metres. They are a kind of foraminiferan that extract minerals from their surroundings and use them to form an exoskeleton known as a test.
Foraminifera are single-celled organisms, members of a phylum or class of Rhizarian protists characterized by streaming granular ectoplasm for catching food and other uses; and commonly an external shell of diverse forms and materials. Tests of chitin are believed to be the most primitive type. Most foraminifera are marine, the majority of which live on or within the seafloor sediment, while a smaller number float in the water column at various depths, which belong to the suborder Globigerinina. Fewer are known from freshwater or brackish conditions, and some very few (nonaquatic) soil species have been identified through molecular analysis of small subunit ribosomal DNA.
Gromia is a genus of protists, closely related to foraminifera, which inhabit marine and freshwater environments. It is the only genus of the family Gromiidae. Gromia are ameboid, producing filose pseudopodia that extend out from the cell's proteinaceous test through a gap enclosed by the cell's oral capsule. The test, a shell made up of protein that encloses the cytoplasm, is made up of several layers of membrane, which resemble honeycombs in shape – a defining character of this genus.
The Allogromiida is an order of single-chambered, mostly organic-walled foraminiferans, including some that produce agglutinated tests (Lagynacea). Genetic studies indicate that some foraminiferans with agglutinated tests, previously included in the Textulariida or as their own order Astrorhizida, may also belong here. Allogromiids produce relatively simple tests, usually with a single chamber, similar to those of other protists such as Gromia. They are found as both marine and freshwater forms, and are the oldest forms known from the fossil record.
The Komokiacea are a small group of amoeboid protozoa, considered to be foraminifera, though there have been suggestions that they are a separate group, closely related to foraminifera. Komokiacea are rather large organisms, often exceeding 300 micrometers in maximum dimensions. Along with Xenophyophores they dominate the macro- and megabenthic fauna in the deep sea and are commonly referred to as "giants protists".
Marine ecosystems are the largest of Earth's aquatic ecosystems and exist in waters that have a high salt content. These systems contrast with freshwater ecosystems, which have a lower salt content. Marine waters cover more than 70% of the surface of the Earth and account for more than 97% of Earth's water supply and 90% of habitable space on Earth. Seawater has an average salinity of 35 parts per thousand of water. Actual salinity varies among different marine ecosystems. Marine ecosystems can be divided into many zones depending upon water depth and shoreline features. The oceanic zone is the vast open part of the ocean where animals such as whales, sharks, and tuna live. The benthic zone consists of substrates below water where many invertebrates live. The intertidal zone is the area between high and low tides. Other near-shore (neritic) zones can include mudflats, seagrass meadows, mangroves, rocky intertidal systems, salt marshes, coral reefs, lagoons. In the deep water, hydrothermal vents may occur where chemosynthetic sulfur bacteria form the base of the food web.
Elphidium is an abundant genus of foraminifera. Species can be found from coastal regions out to the continental slope, and in all temperature ranges. Like other forams, fossils from different species are used to date rocks. The taxonomy of the species within this genus is disputed due to the high variability of some species.
Lukas Hottinger was a paleontologist, biologist and geologist. Hottinger collaborated with the Natural History Museum of Basel (Switzerland).
Macrobenthos consists of the organisms that live at the bottom of a water column and are visible to the naked eye. In some classification schemes, these organisms are larger than 1 mm; in another, the smallest dimension must be at least 0.5 mm. They include polychaete worms, pelecypods, anthozoans, echinoderms, sponges, ascidians, crustaceans.
Quinqueloculina is a genus of foraminifera in the family Miliolidae.
Ammonia tepida is a benthic foraminifer living in the sediment of brackish waters. It is very similar to Ammonia beccarii, but the latter lives on the surface of red algae. Once considered a globally widespread taxon, a recent genetic and morphological study has revealed that many of what were once considered members of A. tepida in fact represent other species of Ammonia, primarily Ammonia veneta, with true specimens of A. tepida only being found in Atlantic waters, off the coast of the Americas.
Globigerinana are free living pelagic foraminiferan, included in the class Rotaliata that range from the Jurassic to recent. Test are commonly planospiral or trochospiral but may be uniserial to multiserial and are of secreted hyaline (glassy) calcite. Chambers are flattened in planospiral forms and spheroidal in trochospiral and serial forms. Some have long radial spines, or needles that may be solidly fixed or moveable in sockets. Gametes are biflagellate and are produced in greater number than by bottom dwelling benthic forms.
Stercomata are extracellular pellets of waste material produced by some groups of foraminiferans, including xenophyophoreans and komokiaceans, Gromia, and testate amoebae. The pellets are ovoid (egg-shaped), brownish in color, and on average measure from 10-20 µm in length. Stercomata are composed of small mineral grains and undigested waste products held together by strands of glycosaminoglycans.
Ammonia is a genus of marine foraminifers. It is one of the most abundant foraminifer genera worldwide and occurs in sheltered and shallow marine intertidal environments, sometimes in brackish waters.
"Monothalamea" is a grouping of foraminiferans, traditionally consisting of all foraminifera with single-chambered tests. Recent work has shown that the grouping is paraphyletic, and as such does not constitute a natural group; nonetheless, the name "monothalamea" continues to be used by foraminifera workers out of convenience.
Bruce William Hayward is a New Zealand geologist, marine ecologist, and author. He is known as a leading expert on living and fossil foraminifera.
Foraminiferal tests are the tests of Foraminifera.
Global paleoclimate indicators are the proxies sensitive to global paleoclimatic environment changes. They are mostly derived from marine sediments. Paleoclimate indicators derived from terrestrial sediments, on the other hand, are commonly influenced by local tectonic movements and paleogeographic variations. Factors governing the Earth's climate system include plate tectonics, which controls the configuration of continents, the interplay between the atmosphere and the ocean, and the Earth's orbital characteristics. Global paleoclimate indicators are established based on the information extracted from the analyses of geologic materials, including biological, geochemical and mineralogical data preserved in marine sediments. Indicators are generally grouped into three categories; paleontological, geochemical and lithological.
Orcadia riedeli is a planktonic marine foraminifera. It is the only species in the monotypic genus Orcadia. It was originally classified in the genus Hastigerinella. It is found in the surface water of oceans and has a cosmopolitan distribution. The phylogenetic position of this genus remains enigmatic; it was originally assigned to the family Hastigerinidae, but was later moved to Globigerinellidae, in the order Globigerinida.
