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Onilahy River

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Onilahy is a river in Atsimo-Andrefana and Anosy ( Toliara Province ), southern Madagascar . It flows down from the hills near Betroka to the Mozambique Channel . It empties at St. Augustin ( 23°34′00″S 43°45′00″E  /  23.5666667°S 43.75°E  / -23.5666667; 43.75 ), and into the Bay of Saint-Augustin .

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65-539: Two species of cichlids are endemic to the river basin , but Ptychochromis onilahy is probably already extinct and the remaining range of Ptychochromoides betsileanus covers less than 10 square kilometres (3.9 sq mi). Sources of the Onilahy river are near Beadabo . It flows through Ankilimary , to Benenitra , Ehara , Bezaha and Antanimena . It is crossed by the RN 10 near Tameantsoa . The mouth of

130-474: A tribe of cichlids in subfamily Pseudocrenilabrinae called Haplochromini . This group includes the type genus Haplochromis plus a number of closely related genera such as Aulonocara , Astatotilapia , and Chilotilapia . They are endemic to eastern , southern and northern Africa , except for Astatotilapia flaviijosephi in the Middle East . A common name in a scientific context

195-419: 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

260-468: 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

325-401: 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

390-604: 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

455-480: 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

520-507: 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

585-442: 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

650-505: 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

715-491: 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

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780-528: 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,

845-499: 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

910-433: Is East African cichlids – while they are not restricted to that region, they are the dominant Cichlidae there. This tribe was extensively studied by Ethelwynn Trewavas , who made major reviews in 1935 and 1989, at the beginning and at the end of her career in ichthyology . Even today, numerous new species are being described each year. The haplochromines were in older times treated as subfamily Haplochrominae , However,

975-504: 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

1040-514: 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

1105-469: 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

1170-717: 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

1235-544: 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

1300-534: 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

1365-401: Is the lake species that have been most closely studied because of the species flocks known from some of the larger lakes, such as Lake Malawi . In the aquarium hobby, the "happies" are conveniently divided into four groups:  Lake Victoria's trophic web was thoroughly upset in the second half of the 20th century, after Nile Perch ( Lates niloticus ) were introduced to the lake. Among

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1430-596: 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

1495-473: 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

1560-974: 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

1625-404: 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

1690-606: The aquarium hobby, these fishes are popular; however due to their often aggressive behaviors and rather unusual water parameters, they are generally unsuitable for beginners or community tanks. There are some informal names used among aquarists for Haplochromini. Generally, any and all (as well as some similar-looking Pseudocrenilabrinae) may be referred to haplos , haps or happies . More specific terms are mbuna ("rock-dwelling browser") and utaka ("free-roaming hunter"), which are Bantu terms for these two ecological groups. Haplochromines inhabit both rivers and lakes, but it

1755-599: 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

1820-458: 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

1885-578: The (later-described) Pseudocrenilabrus , even though the tribe name Pseudocrenilabrini was proposed earlier. In the African Great Lakes , there has been an amazing adaptive radiation of Haplochromini. Many have interesting behavior (e.g. mouthbrooding in Astatotilapia burtoni or the "sleeper" ambushes of Nimbochromis ), and brilliant colors are also widespread. Males and females are often strikingly sexually dichromatic . In

1950-651: 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

2015-535: 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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2080-542: 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

2145-561: 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

2210-759: The Onilahy river is situated in the Indian Ocean at Saint Augustin, Madagascar , 35 km south of Toliara (Tuléar). Its main affluentes from its south are Sakamena river , Evasy River , Ianapera River , Isoanala river and the Ihazofotsy River . From the north these are Sakondry , Taheza , Sakamare and the Imatoto rivers. This article related to a river in Madagascar is a stub . You can help Misplaced Pages by expanding it . Cichlid Alternate taxonomy: For genera , see below . Cichlids / ˈ s ɪ k l ɪ d z / are fish from

2275-495: 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

2340-456: 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

2405-416: 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

2470-892: 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

2535-527: 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,

2600-466: 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

2665-583: 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

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2730-770: 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

2795-439: 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

2860-980: 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

2925-401: 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

2990-453: 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

3055-522: The great African radiation of pseudocrenilabrine cichlids is certainly not monophyletic without them, and thus they are today ranked as a tribe therein. They do include, however, the type genus of the subfamily Pseudocrenilabrus . Since taxonomic tribes are treated like genera for purposes of biological nomenclature according to the ICZN , the Haplochromis is the type genus of this tribe, and not

3120-417: The haplochromines found there, there have been many extinctions , and a number of other species only survive in aquaria. One monotypic genus , Hoplotilapia , is believed to be entirely extinct at least in the wild. As numerous Haplochromini, in particular those species still placed in the " wastebin genus " Haplochromis , are of unclear relationships, the number and validity of genera in this tribe

3185-594: 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

3250-493: 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

3315-602: 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

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3380-821: 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. Haplochromine Haplochrominae Hoedeman, 1947 Pseudocrenilabrini Fowler, 1935 The haplochromine cichlids are

3445-436: 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

3510-814: 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

3575-409: 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,

3640-648: 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

3705-421: 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

3770-404: 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

3835-408: 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

3900-704: 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,

3965-775: 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

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4030-406: 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

4095-478: 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

4160-492: 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

4225-520: 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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