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91-614: The Rift Valley lakes are well known for the evolution of at least 800 cichlid fish species that live in their waters. More species are expected to be discovered. The World Wide Fund for Nature has designated these lakes as one of its Global 200 priority ecoregions for conservation. Lake Malawi and Lake Tanganyika have formed in the various valleys of the East African Rift zone. Lake Kivu's "still waters ... hide another face: dissolved within are billions of cubic meters of flammable methane and more still of carbon dioxide,

182-557: 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 ,

273-419: A behavioral change such that they become less receptive to outside interactions. This is often coupled with some physiological change in appearance. Cichlids can have maternal, paternal, or biparental care. Maternal care is most common among mouthbrooders, but cichlids' common ancestor is thought to exhibit paternal-only care. Other individuals outside of the parents may also play a role in raising young; in

364-468: A group, cichlids exhibit a similar diversity of body shapes, ranging from strongly laterally compressed species (such as Altolamprologus , Pterophyllum , and Symphysodon ) to species that are cylindrical and highly elongated (such as Julidochromis , Teleogramma , Teleocichla , Crenicichla , and Gobiocichla ). Generally, however, cichlids tend to be of medium size, ovate in shape, and slightly laterally compressed, and generally similar to

455-651: 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

546-628: 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,

637-401: A male and female leads to courtship. Courtship in male cichlids follows the establishment of some form of territory, sometimes coupled with building a bower to attract mates. After this, males may attempt to attract female cichlids to their territories by a variety of lekking display strategies or otherwise seek out females of their species. However, cichlids, at the time of spawning, undergo

728-604: A mating partner is unavailable. Pit spawning, also referred to as substrate breeding, is a behavior in cichlid fish in which a fish builds a pit in the sand or ground, where a pair court and consequently spawn. Many different factors go into this behavior of pit spawning, including female choice of the male and pit size, as well as the male defense of the pits once they are dug in the sand. Cichlids are often divided into two main groups: mouthbrooders and substrate brooders. Different parenting investment levels and behaviors are associated with each type of reproduction. As pit spawning

819-480: A minor part of their diets. Other cichlids are detritivores and eat organic material, called Aufwuchs (offal); among these species are the tilapiines of the genera Oreochromis , Sarotherodon , and Tilapia . Other cichlids are predatory and eat little or no plant matter. These include generalists that catch a variety of small animals, including other fishes and insect larvae (e.g. Pterophyllum ), as well as variety of specialists. Trematocranus

910-507: A mixed school of young have also been observed in multiple cichlid species, including Amphilophus citrinellus , Etroplus suratensis , and Tilapia rendalli . Comparably, the fry of Neolamprologus brichardi , a species that commonly lives in large groups, are protected not only by the adults, but also by older juveniles from previous spawns. Several cichlids, including discus ( Symphysodon spp.), some Amphilophus species, Etroplus , and Uaru species, feed their young with

1001-488: A number of amphibian species, including Amietophrynus kisoloensis , Bufo keringyagae , Cardioglossa cyaneospila , and Nectophryne batesii . The Southern Rift Valley lakes are like the Western Rift Valley lakes in that, with one exception, they are freshwater lakes. Cichlid Alternate taxonomy: For genera , see below . Cichlids / ˈ s ɪ k l ɪ d z / are fish from

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1092-409: 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

1183-442: A remarkably rapid change in coloration, during which a successfully dominant territorial male assumes a more vivid and brighter coloration, while a subordinate or "nonterritorial" male assumes a dull-pale coloration. In addition to color displays, cichlids employ their lateral lines to sense movements of water around their opponents to evaluate the competing male for physical traits/fitness. Male cichlids are very territorial due to

1274-505: A skin secretion from mucous glands. The species Neolamprologus pulcher uses a cooperative breeding system, in which one breeding pair has many helpers that are subordinate to the dominant breeders. Parental care falls into one of four categories: substrate or open brooders, secretive cave brooders (also known as guarding speleophils ), and at least two types of mouthbrooders , ovophile mouthbrooders and larvophile mouthbrooders. Open- or substrate-brooding cichlids lay their eggs in

1365-427: 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. ;

1456-491: A time, attaching them to the spawning surface, which may be a pit constructed on the substrate or another surface. The number of eggs laid was correlated to the space available on the substrate. Once the eggs were attached, the male swam over the eggs and fertilized them. The parents would then dig pits in the sand, 10–20 cm wide and 5–10 cm deep, where larvae were transferred after hatching. Larvae began swimming 8 days after fertilization and parenting behaviors and some of

1547-455: 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

1638-528: A very wide variety of food items. This is assumed to be one reason why they are so diverse. The features that distinguish them from the other families in the Labroidei include: Kullander (1998) recognizes eight subfamilies of cichlids: the Astronotinae , Cichlasomatinae , Cichlinae , Etroplinae , Geophaginae , Heterochromidinae , Pseudocrenilabrinae , and Retroculinae . A ninth subfamily,

1729-499: A wider variety of foods based on availability. Carnivorous cichlids can be further divided into piscivorous and molluscivorous, since the morphology and hunting behavior differ greatly between the two categories. Piscivorous cichlids eat other fish, fry, larvae, and eggs. Some species eat the offspring of mouthbrooders by head-ramming, wherein the hunter shoves its head into the mouth of a female to expel her young and eat them. Molluscivorous cichlids have several hunting strategies amongst

1820-549: Is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses . In binomial nomenclature , the genus name forms the first part of the binomial species name for each species within the 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

1911-504: Is a reproductive behavior, many different physiological changes occur in the cichlid while this process is occurring that interfere with social interaction. Different kinds of species that pit spawn, and many different morphological changes occur because of this behavioral experience. Pit spawning is an evolved behavior across the cichlid group. Phylogenetic evidence from cichlids in Lake Tanganyika could be helpful in uncovering

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2002-514: Is a specialized snail -eater, while Pungu maclareni feeds on sponges . A number of cichlids feed on other fish, either entirely or in part. Crenicichla species are stealth predators that lunge from concealment at passing small fish, while Rhamphochromis species are open-water pursuit predators that chase down their prey. Paedophagous cichlids such as the Caprichromis species eat other species' eggs or young, in some cases ramming

2093-469: Is also the case for Etroplus maculatus and E. suratensis from India and Sri Lanka. Within the cichlid family, carnivores, herbivores, omnivores, planktivores, and detritivores are known, meaning the Cichlidae encompass essentially the full range of food consumption possible in the animal kingdom. Various species have morphological adaptations for specific food sources, but most cichlids consume

2184-717: Is based on body movements, such as shaking and pelvic fin flicking. In addition, open- and cave-brooding parents assist in finding food resources for their fry. Multiple neotropical cichlid species perform leaf-turning and fin-digging behaviors. Ovophile mouthbrooders incubate their eggs in their mouths as soon as they are laid, and frequently mouthbrood free-swimming fry for several weeks. Examples include many East African Rift lakes ( Lake Malawi , Lake Tanganyika , and Lake Victoria ) endemics, e.g.: Maylandia , Pseudotropheus , Tropheus , and Astatotilapia burtoni , along with some South American cichlids such as Geophagus steindachneri . Larvophile mouthbrooders lay eggs in

2275-544: Is believed to have been a spit-spawning species. Both Madagascar and Indian cichlids retain this feature. However, of the African cichlids, all extant substrate brooding species originate solely from Lake Tanganyika. The ancestor of the Lake Malawi and Lake Victoria cichlids were mouthbrooders. Similarly, only around 30% of South American cichlids are thought to retain the ancestral substrate-brooding trait. Mouthbrooding

2366-612: 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

2457-534: Is equally at home in freshwater marshes and mangrove swamps, and lives and breeds in saltwater environments such as the mangrove belts around barrier islands . Several species of Tilapia , Sarotherodon , and Oreochromis are euryhaline and can disperse along brackish coastlines between rivers. Only a few cichlids, however, inhabit primarily brackish or salt water, most notably Etroplus maculatus , Etroplus suratensis , and Sarotherodon melanotheron . The perhaps most extreme habitats for cichlids are

2548-460: 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,

2639-474: 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

2730-596: Is thought to have evolved individually up to 14 times, and a return to substrate brooding as many as three separate times between both African and Neotropical species. Cichlids have a great variety of behaviors associated with substrate brooding, including courtship and parental care alongside the brooding and nest-building behaviors needed for pit spawning. Cichlids' behavior typically revolves around establishing and defending territories when not courting, brooding, or raising young. Encounters between males and males or females and females are agonistic, while an encounter between

2821-516: The African Great Lakes . The Western Rift Valley lakes are fresh water and home to an extraordinary number of species. Approximately 1,500 cichlid fish (Cichlidae) species live in the lakes. In addition to the cichlids, populations of Clariidae , Claroteidae , Mochokidae , Poeciliidae , Mastacembelidae , Centropomidae , Cyprinidae , Clupeidae and other fish families are found in these lakes. They are also important habitats for

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2912-621: 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

3003-824: 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;

3094-473: The Ptychochrominae , was later recognized by Sparks and Smith. Cichlid taxonomy is still debated, and classification of genera cannot yet be definitively given. A comprehensive system of assigning species to monophyletic genera is still lacking, and there is not complete agreement on what genera should be recognized in this family. As an example of the classification problems, Kullander placed

3185-974: The Rio Grande in South Texas . Madagascar has its own distinctive species ( Katria , Oxylapia , Paratilapia , Paretroplus , Ptychochromis , and Ptychochromoides ), only distantly related to those on the African mainland. Native cichlids are largely absent in Asia, except for 9 species in Israel , Lebanon , and Syria ( Astatotilapia flaviijosephi , Oreochromis aureus , O. niloticus , Sarotherodon galilaeus , Coptodon zillii , and Tristramella spp.), two in Iran ( Iranocichla ), and three in India and Sri Lanka ( Etroplus and Pseudetroplus ). If disregarding Trinidad and Tobago (where

3276-404: The angelfish , oscars , and discus . Cichlids have the largest number of endangered species among vertebrate families, most in the haplochromine group. Cichlids are particularly well known for having evolved rapidly into many closely related but morphologically diverse species within large lakes, particularly Lakes Tanganyika , Victoria , Malawi , and Edward . Their diversity in

3367-599: The family Cichlidae in the order Cichliformes . Traditionally Cichlids were classed in a suborder, the Labroidei , along with the wrasses ( Labridae ), in the order Perciformes , but molecular studies have contradicted this grouping. On the basis of fossil evidence, it first appeared in Argentina during the Early Eocene epoch, about 48.6 million years ago; however, molecular clock estimates have placed

3458-458: The new world , can be classified under the subfamily Cichlinae, while Etroplinae can classify all cichlid species native to the old world . Cichlids are one of the largest vertebrate families in the world. They are most diverse in Africa and South America. Africa alone is host to at least an estimated 1,600 species. Central America and Mexico have about 120 species, as far north as

3549-404: 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,

3640-651: The African Great Lakes is important for the study of speciation in evolution. Many cichlids introduced into waters outside of their natural range have become nuisances. All cichlids practice some form of parental care for their eggs and fry, usually in the form of guarding the eggs and fry or mouthbrooding . Cichlids span a wide range of body sizes, from species as small as 2.5 cm (1 in) in length (e.g., female Neolamprologus multifasciatus ) to much larger species approaching 1 m (3 ft) in length ( Boulengerochromis and Cichla ). As

3731-535: The African cichlids, can be further split either into Eastern and Western varieties, or into groups depending on which lake the species is from: Lake Malawi , Lake Victoria , or Lake Tanganyika . Of these subgroups, the Madagascar and Indian cichlids are the most basal and least diverse. Of the African cichlids, the West African or Lake Tanganyika cichlids are the most basal. Cichlids' common ancestor

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3822-542: The African genus Heterochromis phylogenetically within Neotropical cichlids, although later papers concluded otherwise. Other problems center upon the identity of the putative common ancestor for the Lake Victoria superflock (many closely related species sharing a single habitat), and the ancestral lineages of Lake Tanganyikan cichlids. Phylogeny derived from morphological characters shows differences at

3913-660: The Central African lakes. Lakes Albert, Victoria, and Edward are part of the Nile River basin. Lake Victoria (elevation 1,134 metres (3,720 ft)), with an area of 68,800 square kilometres (26,600 sq mi), is the largest lake in Africa. It is not in the Rift Valley, instead occupying a depression between the eastern and western rifts formed by the uplift of the rifts to either side. Lakes Victoria, Tanganyika, and Malawi are sometimes collectively known as

4004-606: The Ethiopian Rift Valley lakes are of great importance to Ethiopia's economy, as well as being essential to the survival of the local people, there were no intensive and extensive limnological studies undertaken of these lakes until recently. The major ones are Lake Tana , the source of the Blue Nile , lies in the Ethiopian highlands north of the Rift Valley; however, it is not a Rift Valley lake. South of

4095-724: The Ethiopian highlands, the rift valley splits into two major troughs. The Eastern Rift is home to the Kenyan Rift Valley lakes, while most of the Central African Rift Valley lakes lie in the Western Rift. This area includes the Gregory Rift in Kenya and Tanzania. The Kenyan section of the Rift Valley is home to eight lakes, of which three are freshwater and the rest alkaline. Of the latter,

4186-473: 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

4277-561: The North American sunfishes in morphology, behavior, and ecology. Cichlids share a single key trait - the fusion of the lower pharyngeal bones into a single tooth-bearing structure. A complex set of muscles allows the upper and lower pharyngeal bones to be used as a second set of jaws for processing food, allowing a division of labor between the "true jaws" ( mandibles ) and the " pharyngeal jaws ". Cichlids are efficient and often highly specialized feeders that capture and process

4368-495: The anal fin (specifically the genital papilla) of the male, which is when he discharges sperm into her mouth and fertilizes the eggs. The genuine color of egg spots is a yellow, red, or orange inner circle with a colorless ring surrounding the shape. Through phylogenetic analysis, using the mitochondrial ND2 gene, the true egg spots are thought to have evolved in the common ancestor of the Astatoreochromis lineage and

4459-442: 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

4550-456: The biparental daffodil cichlid ( Neolamprologus pulcher ), closely related satellite males, those males that surround other males' territories and attempt to mate with female cichlids in the area, help rear the primary males' offspring and their own. A common form of brood care involves food provisioning. For example, females of lyretail cichlids ( Neolamprologus modabu ) dig at sandy substrate more to push nutritional detritus and zooplankton into

4641-416: The cichlid tribe Haplochromini, exhibit a unique pattern of oval-shaped color dots on their anal fins. These phenomena, known as egg spots, aid in the mouthbrooding mechanisms of cichlids. The egg spots consist of carotenoid-based pigment cells, which indicate a high cost to the organism, when considering that fish are not able to synthesize their own carotenoids. The mimicry of egg spots is used by males for

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4732-892: The details, the general basis of the behavior is the same. Mouthbrooding also affects how they choose their mates and breeding grounds. In a 1995 study, Nelson found that in pit-spawning females choose males for mating based on the size of the pit that they dig, as well as some of the physical characteristics seen in the males. Pit spawning also differs from mouth brooding in the size and postnatal care exhibited. Eggs that have been hatched from pit-spawning cichlids are usually smaller than those of mouthbrooders. Pit-spawners' eggs are usually around 2 mm, while mouthbrooders are typically around 7 mm. While different behaviors take place postnatally between mouthbrooders and pit spawners, some similarities exist. Females in both mouthbrooders and pit-spawning cichlids take care of their young after they are hatched. In some cases, both parents exhibit care, but

4823-527: The entire clade and within different communities across separate habitats. Within their phylogeny, many parallel instances are seen of lineages evolving to the same trait and multiple cases of reversion to an ancestral trait. The family Cichlidae arose between 80 and 100 million years ago within the order Perciformes (perch-like fishes). Cichlidae can be split into a few groups based on their geographic location: Madagascar, Indian, African, and Neotropical (or South American). The most famous and diverse group,

4914-466: The evolution of their reproductive behaviors. Several important behaviors are associated with pit spawning, including parental care, food provisioning, and brood guarding. One of the differences studied in African cichlids is reproductive behavior. Some species pit spawn and some are known as mouth brooders. Mouthbrooding is a reproductive technique where the fish scoop up eggs and fry for protection. While this behavior differs from species to species in

5005-583: The family's origin as far back as 67 million years ago, during the late Cretaceous period. The closest living relative of cichlids is probably the convict blenny , and both families are classified in the 5th edition of Fishes of the World as the two families in the Cichliformes, part of the subseries Ovalentaria . This family is large, diverse, and widely dispersed. At least 1,650  species have been scientifically described , making it one of

5096-770: The female always cares for the eggs and newly hatched fry. Many species of cichlids use pit spawning, but one of the less commonly studied species that exhibits this behavior is the Neotropical Cichlasoma dimerus . This fish is a substrate breeder that displays biparental care after the fry have hatched from their eggs. One study examined reproductive and social behaviors of this species to see how they accomplished their pit spawning, including different physiological factors such as hormone levels, color changes, and plasma cortisol levels. The entire spawning process could take about 90 minutes and 400~800 eggs could be laid. The female deposits about 10 eggs at

5187-439: The fertilization process. Mouthbrooding females lay eggs and immediately snatch them up with their mouths. Over millions of years, male cichlids have evolved egg spots to initiate the fertilization process more efficiently. When the females are snatching up the eggs into their mouth, the males gyrate their anal fins, which illuminates the egg spots on his tail. Afterwards, the female, believing these are her eggs, places her mouth to

5278-980: The few native cichlids are members of genera that are widespread in the South American mainland), the three species from the genus Nandopsis are the only cichlids from the Antilles in the Caribbean , specifically Cuba and Hispaniola . Europe, Australia, Antarctica, and North America north of the Rio Grande drainage have no native cichlids, although in Florida , Hawaii , Japan, northern Australia, and elsewhere, feral populations of cichlids have become established as exotics . Although most cichlids are found at relatively shallow depths, several exceptions do exist. The deepest known occurrences are Trematocara at more than 300 m (1,000 ft) below

5369-446: 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

5460-401: The full range of parenting behaviours. Secretive cave-spawning cichlids lay their eggs in caves, crevices, holes, or discarded mollusc shells , frequently attaching the eggs to the roof of the chamber. Examples include Pelvicachromis spp., Archocentrus spp., and Apistogramma spp. Free-swimming fry and parents communicate in captivity and in the wild. Frequently, this communication

5551-737: 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,

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5642-453: The genus level with phylogeny based on genetic loci . A consensus remains that the Cichlidae as a family are monophyletic. In cichlid taxonomy, dentition was formerly used as a classifying characteristic, but this was complicated because in many cichlids, tooth shapes change with age, due to wear, and cannot be relied upon. Genome sequencing and other technologies transformed cichlid taxonomy. Alternatively, all cichlid species native to

5733-594: The heads of mouthbrooding species to force them to disgorge their young. Among the more unusual feeding strategies are those of Corematodus , Docimodus evelynae , Plecodus , Perissodus , and Genyochromis spp., which feed on scales and fins of other fishes, a behavior known as lepidophagy , along with the death-mimicking behaviour of Nimbochromis and Parachromis species, which lay motionless, luring small fish to their side prior to ambush. This variety of feeding styles has helped cichlids to inhabit similarly varied habitats. Its pharyngeal teeth (in

5824-432: 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

5915-493: The largest vertebrate families. New species are discovered annually, and many species remain undescribed . The actual number of species is therefore unknown, with estimates varying between 2,000 and 3,000. Many cichlids, particularly tilapia , are important food fishes, while others, such as the Cichla species, are valued game fish. The family also includes many popular freshwater aquarium fish kept by hobbyists, including

6006-633: 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,

6097-602: The modern Haplochrominis species. This ancestor was most likely riverine in origin, based on the most parsimonious representation of habitat type in the cichlid family. The presence of egg spots in a turbid riverine environment would seem particularly beneficial and necessary for intraspecies communication. Two pigmentation genes are found to be associated with egg-spot patterning and color arrangement. These are fhl2-a and fhl2-b , which are paralogs. These genes aid in pattern formation and cell-fate determination in early embryonic development. The highest expression of these genes

6188-403: 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

6279-428: 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

6370-790: The open or in a cave and take the hatched larvae into the mouth. Examples include some variants of Geophagus altifrons , and some Aequidens , Gymnogeophagus , and Satanoperca , as well as Oreochromis mossambicus and Oreochromis niloticus . Mouthbrooders, whether of eggs or larvae, are predominantly females. Exceptions that also involve the males include eretmodine cichlids (genera Spathodus , Eretmodus , and Tanganicodus ), some Sarotherodon species (such as Sarotherodon melanotheron ), Chromidotilapia guentheri , and some Aequidens species. This method appears to have evolved independently in several groups of African cichlids. Genus Genus ( / ˈ dʒ iː n ə s / ; pl. : genera / ˈ dʒ ɛ n ər ə / )

6461-436: The open, on rocks, leaves, or logs. Examples of open-brooding cichlids include Pterophyllum and Symphysodon species and Anomalochromis thomasi . Male and female parents usually engage in differing brooding roles. Most commonly, the male patrols the pair's territory and repels intruders, while the female fans water over the eggs, removing the infertile ones, and leading the fry while foraging. Both sexes are able to perform

6552-814: The physical aggression of males becomes a contest for resources (mates, territory, food). Female cichlids prefer to mate with a successfully alpha male with vivid coloration, whose territory has food readily available. Cichlids mate either monogamously or polygamously . The mating system of a given cichlid species is not consistently associated with its brooding system. For example, although most monogamous cichlids are not mouthbrooders, Chromidotilapia , Gymnogeophagus , Spathodus , and Tanganicodus all include – or consist entirely of – monogamous mouthbrooders. In contrast, numerous open- or cave-spawning cichlids are polygamous; examples include many Apistogramma , Lamprologus , Nannacara , and Pelvicachromis species. Most adult male cichlids, specifically in

6643-409: The physiological factors measured changed. In the same study, color changes were present before and after the pit spawning occurred. For example, after the larvae were transferred and the pits were beginning to be protected, their fins turned a dark grey color. In another study, of the rainbow cichlid, Herotilapia multispinosa , color changes occurred throughout the spawning process. Before spawning,

6734-648: The precise sister relationships predicted by vicariance : Africa-South America and India-Madagascar. The dispersal hypothesis, in contrast, requires cichlids to have negotiated thousands of kilometers of open ocean between India and Madagascar without colonizing any other island, or for that matter, crossing the Mozambique Channel to Africa. Although the vast majority of Malagasy cichlids are entirely restricted to fresh water, Ptychochromis grandidieri and Paretroplus polyactis are commonly found in coastal brackish water and are apparently salt tolerant, as

6825-421: The pressure of reproduction, and establish their territory and social status by physically driving out challenging males (novel intruders) through lateral displays (parallel orientation, uncovering gills), biting, or mouth fights (head-on collisions of open mouths, measuring jaw sizes, and biting each other's jaws). The cichlid social dichotomy is composed of a single dominant with multiple subordinates, where

6916-541: 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

7007-404: The rainbow cichlid was an olive color with grey bands. Once spawning behaviors started, the body and fins of the fish became a more golden color. When the eggs were finished being laid, the pelvic fin all the way back to the caudal fin turned to a darker color and blackened in both the males and the females. Females prefer a bigger pit size when choosing where to lay eggs. Differences are seen in

7098-748: The result of volcanic gases seeping in." The Ethiopian Rift Valley lakes are the northernmost of the African Rift Valley lakes. In central Ethiopia , the Main Ethiopian Rift , also known as the Great Rift Valley, splits the Ethiopian highlands into northern and southern halves, and the Ethiopian Rift Valley lakes occupy the floor of the rift valley between the two highlands. Most of the Ethiopian Rift Valley lakes do not have an outlet, and most are alkaline . Although

7189-661: The shallow soda lakes of the Eastern Rift Valley have crystallised salt turning the shores white and are famous for the large flocks of flamingo that feed on crustaceans . All the lakes in the Tanzanian section of this group are alkaline: The lakes of the Western or Albertine Rift , with Lake Victoria , include the largest, deepest, and oldest of the Rift Valley Lakes. They are also referred to as

7280-408: The sizes of pits that created, as well as a change in the morphology of the pits. Evolutionary differences between species of fish may cause them to either create pits or castles when spawning. The differences were changes in the way that each species fed, their macrohabitats, and the abilities of their sensory systems. Cichlids are renowned for their recent, rapid evolutionary radiation, both across

7371-497: 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,

7462-412: 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

7553-704: The surface in Lake Tanganyika . Others found in relatively deep waters include species such as Alticorpus macrocleithrum and Pallidochromis tokolosh down to 150 m (500 ft) below the surface in Lake Malawi, and the whitish (non pigmented ) and blind Lamprologus lethops , which is believed to live as deep as 160 m (520 ft) below the surface in the Congo River . Cichlids are less commonly found in brackish and saltwater habitats, though many species tolerate brackish water for extended periods; Mayaheros urophthalmus , for example,

7644-775: The surrounding water. Adult of N. modabu perform this strategy to collect food for themselves, but dig more when offspring are present, likely to feed their fry. This substrate-disruption strategy is rather common and can also be seen in convict cichlids ( Cichlasoma nigrofasciatum ). Other cichlids have an ectothermal mucus that they grow and feed to their young, while still others chew and distribute caught food to offspring. These strategies, however, are less common in pit-spawning cichlids. Cichlids have highly organized breeding activities. All species show some form of parental care for both eggs and larvae , often nurturing free-swimming young until they are weeks or months old. Communal parental care, where multiple monogamous pairs care for

7735-403: 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

7826-406: The throat) afford cichlids so many "niche" feeding strategies, because the jaws pick and hold food, while the pharyngeal teeth crush the prey. Aggressive behavior in cichlids is ritualized and consists of multiple displays used to seek confrontation while being involved in evaluation of competitors, coinciding with temporal proximity to mating. Displays of ritualized aggression in cichlids include

7917-576: 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

8008-478: The varieties within the group. Lake Malawi cichlids consume substrate and filter it out through their gill rakers to eat the mollusks that were in the substrate. Gill rakers are finger-like structures that line the gills of some fish to catch any food that might escape through their gills. Many cichlids are primarily herbivores , feeding on algae (e.g. Petrochromis ) and plants (e.g. Etroplus suratensis ). Small animals, particularly invertebrates , are only

8099-429: 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

8190-492: The warm hypersaline lakes where the members of the genera Alcolapia and Danakilia are found. Lake Abaeded in Eritrea encompasses the entire distribution of D. dinicolai , and its temperature ranges from 29 to 45 °C (84 to 113 °F). With the exception of the species from Cuba, Hispaniola, and Madagascar, cichlids have not reached any oceanic island and have a predominantly Gondwanan distribution, showing

8281-520: Was temporally correlated with egg-spot formation. A short, interspersed, repetitive element was also seen to be associated with egg spots. Specifically, it was evident upstream of the transcriptional start site of fhl2 in only Haplochrominis species with egg spots The cichlid Benitochromis nigrodorsalis from Western Africa ordinarily undergoes biparental reproduction, but is also able to undergo facultative (optional) selfing ( self-fertilization ). Facultative selfing may be an adaptive option when

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