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59-488: Ancistrus is a genus of nocturnal freshwater fish in the family Loricariidae of order Siluriformes , native to freshwater habitats in South America and Panama . Fish of this genus are common in the aquarium trade where they are known as bushynose or bristlenose catfish . In the aquarium hobby they are often referred to as bushynose or bristlenose plecos instead, but this may lead to confusion as "pleco" usually

118-557: A species : see Botanical name and Specific name (zoology) . The rules for the scientific names of organisms are laid down in the nomenclature codes , which allow each species a single unique name that, for animals (including protists ), plants (also including algae and fungi ) and prokaryotes ( bacteria and archaea ), is Latin and binomial in form; this contrasts with common or vernacular names , which are non-standardized, can be non-unique, and typically also vary by country and language of usage. Except for viruses ,

177-421: A "winter kill". Oxygen depletion can result from a number of natural factors, but is most often a concern as a consequence of pollution and eutrophication in which plant nutrients enter a river, lake, or ocean, and phytoplankton blooms are encouraged. While phytoplankton, through photosynthesis , will raise DO saturation during daylight hours, the dense population of a bloom reduces DO saturation during

236-419: A foot in captivity), the bristlenose plecos do not usually exceed six inches in length; they can thus be kept in relatively small tanks, contributing to their popularity in the aquarium hobby. Ancistrus species are unusual among vertebrates in possessing an X0 sex-determination system , which is the prevailing method in many lineages of arthropod but is very rare elsewhere in the animal kingdom. Ancistrus

295-507: A fry mimic to attract females, which would allow males without eggs in their nest to compete with males guarding eggs. Several clutches in various states of development from eggs to free-swimming larvae can be found in one nest. These fish are often kept by aquarists, as they are dutiful algae-eaters and smaller in adult size than the common plecos usually seen in pet shops. They reach up to 15 cm (5.9 in) in males, and 12 cm (4.7 in) in females. Their recommended temperature

354-643: A later homonym of a validly published name is a nomen illegitimum or nom. illeg. ; for a full list refer to the International Code of Nomenclature for algae, fungi, and plants and the work cited above by Hawksworth, 2010. In place of the "valid taxon" in zoology, the nearest equivalent in botany is " correct name " or "current name" which can, again, differ or change with alternative taxonomic treatments or new information that results in previously accepted genera being combined or split. Prokaryote and virus codes of nomenclature also exist which serve as

413-621: A long time and redescribed as new by a range of subsequent workers, or if a range of genera previously considered separate taxa have subsequently been consolidated into one. For example, the World Register of Marine Species presently lists 8 genus-level synonyms for the sperm whale genus Physeter Linnaeus, 1758, and 13 for the bivalve genus Pecten O.F. Müller, 1776. Within the same kingdom, one generic name can apply to one genus only. However, many names have been assigned (usually unintentionally) to two or more different genera. For example,

472-409: A reference for designating currently accepted genus names as opposed to others which may be either reduced to synonymy, or, in the case of prokaryotes, relegated to a status of "names without standing in prokaryotic nomenclature". An available (zoological) or validly published (botanical) name that has been historically applied to a genus but is not regarded as the accepted (current/valid) name for

531-440: A river into the sea is less dense than salt water, stratification in the water column can result. Vertical mixing between the water bodies is therefore reduced, restricting the supply of oxygen from the surface waters to the more saline bottom waters. The oxygen concentration in the bottom layer may then become low enough for hypoxia to occur. Areas particularly prone to this include shallow waters of semi-enclosed water bodies such as

590-427: A taxon; however, the names published in suppressed works are made unavailable via the relevant Opinion dealing with the work in question. In botany, similar concepts exist but with different labels. The botanical equivalent of zoology's "available name" is a validly published name . An invalidly published name is a nomen invalidum or nom. inval. ; a rejected name is a nomen rejiciendum or nom. rej. ;

649-455: A total of c. 520,000 published names (including synonyms) as at end 2019, increasing at some 2,500 published generic names per year. "Official" registers of taxon names at all ranks, including genera, exist for a few groups only such as viruses and prokaryotes, while for others there are compendia with no "official" standing such as Index Fungorum for fungi, Index Nominum Algarum and AlgaeBase for algae, Index Nominum Genericorum and

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708-443: Is 23–27 °C (73–81 °F). Their lifespan is up to 12 years. They are hardy animals, tolerant to a wide range of water conditions. They breed easily in captivity, and are compatible with most other freshwater fish. Though typically mottled brown or black-and-grey spotted in color, other species are more exotic – spots of bright yellow on a dark background being a common pattern. Albino variants are also common. The albino morph

767-589: Is considered by some to be a minimum for fish of this genus is 25 gallons. There are currently 76 recognized species in this genus: The diet of this genus is typical for a Loricariid – algae , aufwuchs , and detritus, with sediment, sand, and gravel presumably ingested accidentally alongside food items. Despite reports among fish-keepers that they require wood in their diet, no scientific evidence to date supports members of this genus feeding on wood. Bristlenoses do not school but hide when not feeding, juveniles however are typically found in brightly lit shallows at

826-596: Is discouraged by both the International Code of Zoological Nomenclature and the International Code of Nomenclature for algae, fungi, and plants , there are some five thousand such names in use in more than one kingdom. For instance, A list of generic homonyms (with their authorities), including both available (validly published) and selected unavailable names, has been compiled by the Interim Register of Marine and Nonmarine Genera (IRMNG). The type genus forms

885-475: Is formed, removing even more oxygen from the environment in the forms of carbon dioxide, bicarbonate ions, and carbonate. Dissolved inorganic carbon is made at a rate of 2.3–6.5 mg/(m ⋅day). As phytoplankton breakdown, free phosphorus and nitrogen become available in the environment, which also fosters hypoxic conditions. As the breakdown of this phytoplankton takes place, the more phosphorus turns into phosphates, and nitrogens turn into nitrates. This depletes

944-450: Is found at the boundary of anoxic and hypoxic zones. Hypoxia can occur throughout the water column and also at high altitudes as well as near sediments on the bottom. It usually extends throughout 20–50% of the water column, but depends on the water depth and location of pycnoclines (rapid changes in water density with depth). It can occur in 10–80% of the water column. For example, in a 10-meter water column, it can reach up to 2 meters below

1003-444: Is known as a "summer kill". The same phenomena can occur in the winter, but for different reasons. During winter, ice and snow cover can attenuate light, and therefore reduce rates of photosynthesis. The freezing over of a lake also prevents air-water interactions that allow the exchange of oxygen. This creates a lack of oxygen while respiration continues. When the oxygen becomes badly depleted, anaerobic organisms can die, resulting in

1062-750: Is not caused by exposure to light during development, it is a morph controlled by genetics. Historically, commonly available species of Ancistrus were Ancistrus cirrhosus and Ancistrus temminckii ; other species are now available, though exact identification is difficult. Feeding is easy, bristlenoses will graze on algae/ algae wafers and other surface growing organisms as well as eating algae wafers or tablets, flake food, squash, spinach, cucumber, zucchini, green beans peas and even sliced carrots. They have also been known to accept frozen bloodworms as part of their diet. Aquarium specimens may starve for lack of algae or other plant matter; algae wafers or other low-protein foods are recommended. Keepers should watch for

1121-622: Is one of the widest ranging Loricariid genera, and representatives are found in most areas where the family in general is present. Many species are found in the rivers and floodplain areas of the Amazon basin , but there are also species elsewhere in tropical South America, as well as species on the island of Trinidad and two species, A. centrolepis and A. chagresi in Panama . Three species are true cavefish ( troglobites ): A. cryptophthalmus , A. galani and A. formoso . These are

1180-608: Is poisonous to anaerobic bacteria for example. Oxygen depletion is typically expressed as a percentage of the oxygen that would dissolve in the water at the prevailing temperature and salinity. A system with low concentration—in the range between 1 and 30% saturation—is called hypoxic or dysoxic . Most fish cannot live below 30% saturation since they rely on oxygen to derive energy from their nutrients. Hypoxia leads to impaired reproduction of remaining fish via endocrine disruption . A "healthy" aquatic environment should seldom experience less than 80% saturation. The exaerobic zone

1239-460: Is somewhat arbitrary. Although all species within a genus are supposed to be "similar", there are no objective criteria for grouping species into genera. There is much debate among zoologists about whether enormous, species-rich genera should be maintained, as it is extremely difficult to come up with identification keys or even character sets that distinguish all species. Hence, many taxonomists argue in favor of breaking down large genera. For instance,

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1298-474: Is the type species , and the generic name is permanently associated with the type specimen of its type species. Should the specimen turn out to be assignable to another genus, the generic name linked to it becomes a junior synonym and the remaining taxa in the former genus need to be reassessed. In zoological usage, taxonomic names, including those of genera, are classified as "available" or "unavailable". Available names are those published in accordance with

1357-495: Is the amount of particulate organic carbon (POC) overall at a given time, t. G(0) is the concentration of POC before breakdown takes place. k is a rate constant in year-1, and t is time in years. For most POC of phytoplankton, the k is around 12.8 years-1, or about 28 days for nearly 96% of carbon to be broken down in these systems. Whereas for anoxic systems, POC breakdown takes 125 days, over four times longer. It takes approximately 1 mg of oxygen to break down 1 mg of POC in

1416-564: Is used for Hypostomus plecostomus and its allies and is often used as a catchall term for any loricariids remotely resembling that species. The type species is Ancistrus cirrhosus . This genus is the largest genus within the tribe Ancistrini . The name ancistrus derives from the Ancient Greek agkistron "hook" – a reference to the form of the cheek odontodes . The genera Pristiancistrus , Thysanocara and Xenocara are now synonyms of Ancistrus . Ancistrus species show all

1475-621: The International Code of Zoological Nomenclature ; the earliest such name for any taxon (for example, a genus) should then be selected as the " valid " (i.e., current or accepted) name for the taxon in question. Consequently, there will be more available names than valid names at any point in time; which names are currently in use depending on the judgement of taxonomists in either combining taxa described under multiple names, or splitting taxa which may bring available names previously treated as synonyms back into use. "Unavailable" names in zoology comprise names that either were not published according to

1534-799: The International Plant Names Index for plants in general, and ferns through angiosperms, respectively, and Nomenclator Zoologicus and the Index to Organism Names for zoological names. Totals for both "all names" and estimates for "accepted names" as held in the Interim Register of Marine and Nonmarine Genera (IRMNG) are broken down further in the publication by Rees et al., 2020 cited above. The accepted names estimates are as follows, broken down by kingdom: The cited ranges of uncertainty arise because IRMNG lists "uncertain" names (not researched therein) in addition to known "accepted" names;

1593-670: The Waddenzee or the Gulf of Mexico , where land run-off is substantial. In these areas a so-called " dead zone " can be created. Low dissolved oxygen conditions are often seasonal, as is the case in Hood Canal and areas of Puget Sound , in Washington State. The World Resources Institute has identified 375 hypoxic coastal zones around the world, concentrated in coastal areas in Western Europe,

1652-537: The pectoral fin spine of the males of some species. Males also have evertible cheek odontodes which are less developed or absent in females. They also lack odontodes along the snout. In comparison with a typical loricariid (pleco), a bristlenose is typically shorter (4–6 inches or 15 cm or less), more flattened and fatter with a comparatively wider head. Colouration is typically mottled brown, grey or black. Small white or yellow spots are common. In contrast to many other loricariid 'plecos' (many of which regularly exceed

1711-404: The platypus belongs to the genus Ornithorhynchus although George Shaw named it Platypus in 1799 (these two names are thus synonyms ) . However, the name Platypus had already been given to a group of ambrosia beetles by Johann Friedrich Wilhelm Herbst in 1793. A name that means two different things is a homonym . Since beetles and platypuses are both members of the kingdom Animalia,

1770-759: The Eastern and Southern coasts of the US, and East Asia, particularly in Japan. Hypoxia may also be the explanation for periodic phenomena such as the Mobile Bay jubilee , where aquatic life suddenly rushes to the shallows, perhaps trying to escape oxygen-depleted water. Recent widespread shellfish kills near the coasts of Oregon and Washington are also blamed on cyclic dead zone ecology. Phytoplankton are mostly made up of lignin and cellulose, which are broken down by oxidative mechanism, which consume oxygen. The breakdown of phytoplankton in

1829-469: The French botanist Joseph Pitton de Tournefort (1656–1708) is considered "the founder of the modern concept of genera". The scientific name (or the scientific epithet) of a genus is also called the generic name ; in modern style guides and science, it is always capitalised. It plays a fundamental role in binomial nomenclature , the system of naming organisms , where it is combined with the scientific name of

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1888-437: The abdomen to take on a sunken appearance, indicating insufficient nutrition. Sexing is very easy as the female will only occasionally have bristles, around the edge of the chin, whereas the male will have them up the center of the head. Breeding is also possible. Males attract females to a small cave or hollow, then guard eggs after fertilization through hatching (4–8 days) until fry are free swimming (4–6 days after hatching);

1947-610: The aquarist need only supply a suitable cave, food, and one of each sex. Caution should be taken with the spines (odontodes); although the risk of personal injury is small with this genus, the hooked nature of the odontodes means that a bristlenose may become trapped in non-natural material such as sponge filters and netting. Genus The composition of a genus is determined by taxonomists . The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including

2006-411: The atmosphere and natural waters. Atmospheric hypoxia occurs naturally at high altitudes . Total atmospheric pressure decreases as altitude increases, causing a lower partial pressure of oxygen, which is defined as hypobaric hypoxia. Oxygen remains at 20.9% of the total gas mixture, differing from hypoxic hypoxia , where the percentage of oxygen in the air (or blood) is decreased. This is common in

2065-442: The base for higher taxonomic ranks, such as the family name Canidae ("Canids") based on Canis . However, this does not typically ascend more than one or two levels: the order to which dogs and wolves belong is Carnivora ("Carnivores"). The numbers of either accepted, or all published genus names is not known precisely; Rees et al., 2020 estimate that approximately 310,000 accepted names (valid taxa) may exist, out of

2124-689: The clutch by fanning them with its pectoral and pelvic fins. During this time, a male usually will not leave the cavity to feed, or will leave only occasionally and quickly return. The eggs hatch in 4–10 days over a period of 2–6 hours; the male guards the eggs for 7–10 days after hatching. The fry remain in the cave, attaching to the walls and ceiling with their mouths, absorbing their yolk sac in 2–4 days and becoming free swimming. Males of these species are competitive and territorial. Males display to each other by positioning themselves parallel to each other, head to tail, with dorsal and caudal fins erect and cheek odontode spines everted. If this escalates to combat,

2183-542: The environment depends on the presence of oxygen, and once oxygen is no longer in the bodies of water, ligninperoxidases cannot continue to break down the lignin. When oxygen is not present in the water, the time required for breakdown of phytoplankton changes from 10.7 days to a total of 160 days. The rate of phytoplankton breakdown can be represented using this equation: G ( t ) = G ( 0 ) e − k t {\displaystyle G(t)=G(0)e^{-kt}} In this equation, G(t)

2242-601: The environment, and therefore, hypoxia takes place quickly as oxygen is used up quickly to digest POC. About 9% of POC in phytoplankton can be broken down in a single day at 18 °C. Therefore, it takes about eleven days to completely break down phytoplankton. After POC is broken down, this particulate matter can be turned into other dissolved carbon, such as carbon dioxide, bicarbonate ions, and carbonate. As much as 30% of phytoplankton can be broken down into dissolved carbon. When this particulate organic carbon interacts with 350 nm ultraviolet light, dissolved inorganic carbon

2301-446: The form "author, year" in zoology, and "standard abbreviated author name" in botany. Thus in the examples above, the genus Canis would be cited in full as " Canis Linnaeus, 1758" (zoological usage), while Hibiscus , also first established by Linnaeus but in 1753, is simply " Hibiscus L." (botanical usage). Each genus should have a designated type , although in practice there is a backlog of older names without one. In zoology, this

2360-727: The generic name (or its abbreviated form) still forms the leading portion of the scientific name, for example, Canis lupus lupus for the Eurasian wolf subspecies, or as a botanical example, Hibiscus arnottianus ssp. immaculatus . Also, as visible in the above examples, the Latinised portions of the scientific names of genera and their included species (and infraspecies, where applicable) are, by convention, written in italics . The scientific names of virus species are descriptive, not binomial in form, and may or may not incorporate an indication of their containing genus; for example,

2419-432: The idea that a newly defined genus should fulfill these three criteria to be descriptively useful: Moreover, genera should be composed of phylogenetic units of the same kind as other (analogous) genera. The term "genus" comes from Latin genus , a noun form cognate with gignere ('to bear; to give birth to'). The Swedish taxonomist Carl Linnaeus popularized its use in his 1753 Species Plantarum , but

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2478-628: The largest component, with 23,236 ± 5,379 accepted genus names, of which 20,845 ± 4,494 are angiosperms (superclass Angiospermae). By comparison, the 2018 annual edition of the Catalogue of Life (estimated >90% complete, for extant species in the main) contains currently 175,363 "accepted" genus names for 1,744,204 living and 59,284 extinct species, also including genus names only (no species) for some groups. The number of species in genera varies considerably among taxonomic groups. For instance, among (non-avian) reptiles , which have about 1180 genera,

2537-452: The lizard genus Anolis has been suggested to be broken down into 8 or so different genera which would bring its ~400 species to smaller, more manageable subsets. Hypoxia (environmental) Hypoxia ( hypo : "below", oxia : "oxygenated") refers to low oxygen conditions. Hypoxia is problematic for air-breathing organisms, yet it is essential for many anaerobic organisms. Hypoxia applies to many situations, but usually refers to

2596-400: The males will circle each other and direct attacks at the head. If an intruding male manages to evict another male from the nest, it may cannibalize the other male's young. A male bristlenose may guard several clutches of eggs simultaneously. Females prefer males that are already protecting eggs and may prefer males that are protecting larvae; it has been suggested that the tentacles may act as

2655-403: The most (>300) have only 1 species, ~360 have between 2 and 4 species, 260 have 5–10 species, ~200 have 11–50 species, and only 27 genera have more than 50 species. However, some insect genera such as the bee genera Lasioglossum and Andrena have over 1000 species each. The largest flowering plant genus, Astragalus , contains over 3,000 species. Which species are assigned to a genus

2714-428: The name could not be used for both. Johann Friedrich Blumenbach published the replacement name Ornithorhynchus in 1800. However, a genus in one kingdom is allowed to bear a scientific name that is in use as a generic name (or the name of a taxon in another rank) in a kingdom that is governed by a different nomenclature code. Names with the same form but applying to different taxa are called "homonyms". Although this

2773-486: The nest. Courtship includes expanding the dorsal and caudal fins and attempts by the male to escort the female to the nest. While the female inspects the nest, the male keeps close contact. The female may lay 20–200 adhesive eggs, usually to the ceiling of the cavity. The female plays no role in parental care; the male takes care of its young. Males will clean the eggs and the cavity with its fins and mouth. Males inspect eggs to remove diseased or infertile eggs, and aerates

2832-435: The night by respiration . When phytoplankton cells die, they sink towards the bottom and are decomposed by bacteria , a process that further reduces DO in the water column. If oxygen depletion progresses to hypoxia, fish kills can occur and invertebrates like worms and clams on the bottom may be killed as well. Hypoxia may also occur in the absence of pollutants. In estuaries, for example, because freshwater flowing from

2891-480: The only known loricariids that possess adaptions for a subterranean lifestyle, such as reduced pigmentation (appearing overall whitish) and eyes. In the wild, Ancistrus species prefer flowing water, so tanks with flow are typically used when keeping them in captivity. Since they are bottom-dwelling fish, substrate is considered preferable to a bare tank floor. Mixtures of gravel, dirt, and clay are frequently used as substrate for Ancistrus . The aquarium size that

2950-526: The provisions of the ICZN Code, e.g., incorrect original or subsequent spellings, names published only in a thesis, and generic names published after 1930 with no type species indicated. According to "Glossary" section of the zoological Code, suppressed names (per published "Opinions" of the International Commission of Zoological Nomenclature) remain available but cannot be used as the valid name for

3009-522: The sealed burrows of some subterranean animals, such as blesmols . Atmospheric hypoxia is also the basis of altitude training , which is a standard part of training for elite athletes. Several companies mimic hypoxia using normobaric artificial atmosphere . An aquatic system lacking dissolved oxygen (0% saturation) is termed anaerobic, reducing , or anoxic . In water, oxygen levels are approximately 7 ppm or 0.0007% in good quality water, but fluctuate. Many organisms require hypoxic conditions. Oxygen

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3068-497: The specific name particular to the wolf. A botanical example would be Hibiscus arnottianus , a particular species of the genus Hibiscus native to Hawaii. The specific name is written in lower-case and may be followed by subspecies names in zoology or a variety of infraspecific names in botany . When the generic name is already known from context, it may be shortened to its initial letter, for example, C. lupus in place of Canis lupus . Where species are further subdivided,

3127-412: The standard format for a species name comprises the generic name, indicating the genus to which the species belongs, followed by the specific epithet, which (within that genus) is unique to the species. For example, the gray wolf 's scientific name is Canis lupus , with Canis ( Latin for 'dog') being the generic name shared by the wolf's close relatives and lupus (Latin for 'wolf') being

3186-419: The surface. In a 20-meter water column, it can extend up to 8 meters below the surface. Hypolimnetic oxygen depletion can lead to both summer and winter "kills". During summer stratification , inputs or organic matter and sedimentation of primary producers can increase rates of respiration in the hypolimnion . If oxygen depletion becomes extreme, aerobic organisms, like fish, may die, resulting in what

3245-403: The taxon is termed a synonym ; some authors also include unavailable names in lists of synonyms as well as available names, such as misspellings, names previously published without fulfilling all of the requirements of the relevant nomenclatural code, and rejected or suppressed names. A particular genus name may have zero to many synonyms, the latter case generally if the genus has been known for

3304-464: The typical features of the Loricariidae. This includes a body covered in bony plates and a ventral suckermouth . The feature most commonly associated with the genus are the fleshy tentacles found on the head in adult males; females may possess tentacles along the snout margin but they are smaller and they lack tentacles on the head. Tentacules , tentacles directly associated with odontodes , develop on

3363-566: The values quoted are the mean of "accepted" names alone (all "uncertain" names treated as unaccepted) and "accepted + uncertain" names (all "uncertain" names treated as accepted), with the associated range of uncertainty indicating these two extremes. Within Animalia, the largest phylum is Arthropoda , with 151,697 ± 33,160 accepted genus names, of which 114,387 ± 27,654 are insects (class Insecta). Within Plantae, Tracheophyta (vascular plants) make up

3422-429: The virus species " Salmonid herpesvirus 1 ", " Salmonid herpesvirus 2 " and " Salmonid herpesvirus 3 " are all within the genus Salmonivirus ; however, the genus to which the species with the formal names " Everglades virus " and " Ross River virus " are assigned is Alphavirus . As with scientific names at other ranks, in all groups other than viruses, names of genera may be cited with their authorities, typically in

3481-405: The water margin making them susceptible to predation by birds. Ancistrus species have the capability of obtaining oxygen through their modified stomach. This allows them to survive in conditions with low oxygen levels . Breeding takes place in hollows, caves and mud holes in banks. Males may clean the inside of the cavity with their suckermouth before allowing the female to approach and inspect

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