Cichlidae
From Palaeos
Cichlids are fishes from the family Cichlidae in the order Perciformes. The family Cichlidae, a major family of perciform fish, is both large and diverse. There are at least 1300 described species [1], making it one of the three largest vertebrate families. Numerous new species are discovered annually, and many species remain undescribed. The actual number of species is therefore unclear, with estimates varying between 1300 and 3000 species (Stiassny et al., 2007), and one source suggesting 1900 species (Kullander, 1998). Cichlids span a wide range of body sizes, from species as small as 2.5 cm in length (e.g. female Neolamprologus multifasciatus ) to much larger species approaching 1 m (e.g. Boulengerochromis and Cichla). As a group, cichlids exhibit a similarly wide diversity of body shapes, ranging from strongly laterally compressed species (such as Altolamprologus, Pterophyllum, and Symphysodon) through to species that are cylindrical and highly elongate (such as Julidochromis, Teleogramma, Teleocichla, Crenicichla, and Gobiocichla) (Loiselle, 1994). Generally, however, cichlids tend to be of medium size, ovate in shape and slightly laterally compressed, and generally very similar to the North American sunfishes in terms of morphology, behaviour, and ecology (Helfman et al., 1997).
Many cichlids, particularly the tilapias, are important food fishes, while others are valued game fish (eg. Cichla species). Many species, including the angelfish, oscars, and discus, are also highly valued in the aquarium trade. Cichlids are particularly well known for having evolved rapidly into a large number of closely related but morphologically diverse species within large lakes, particularly Lakes Tanganyika, Victoria, Malawi and Edward in Africa (Salzburger et al., 2005; Snoeks, 2004). The diversity of cichlids in the African Great Lakes is important for the study of speciation in evolution (Kornfield & Smith, 2000). Many cichlids that have been accidentally or deliberately released into freshwaters outside of their natural range have become nuisance species, for example tilapia in the southern United States [2]
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[edit] Anatomy and appearance
Cichlids are members of a group of perciform fish known as the Labroidei alongside the wrasses (Labridae), damselfish (Pomacentridae), and surfperches (Embiotocidae) (Stiassny & Jensen, 1987). This very large grouping shares 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 labour between the "true jaws" and the "pharyngeal jaws". Cichlids in particular have evolved to be very efficient feeders that are able to capture and process a very wide variety of food items and this is assumed to be one reason why they are so diverse (Loiselle, 1994).
The particular features of cichlids that distinguish them from the other Labroidei include (from Fishbase):
- A single nostril on each side of the forehead instead of two.
- No bony shelf below the orbit of the eye.
- The lateral line organ is divided into two sections, one on the upper half of the flank and a second along the midline of the flank from about halfway along the body to the base of the tail (except for genera Teleogramma and Gobiocichla).
- A distinctively shaped otolith.
- The small intestine leaves the stomach from its left side, not from its right side as in other Labroidei.
[edit] Range and habitat
Cichlids are the most species-rich non-ostariophysan fish family in freshwaters worldwide. They are mainly freshwater fish that are most diverse in Africa and South America. It is estimated that there will be at least 1600 species in Africa alone when all are discovered and described (Nelson, 2006). Substantial numbers are also found in Central America from Panama to the Mexican portion of North America, with approximately 120 species, as far north as the Rio Grande in southern Texas. There are three species found in Cuba and Hispaniola. Madagascar has its own distinctive fauna of cichlids phylogenetically only distantly related to those on the African mainland (Boruchowitz, 2006). Endemic cichlids are largely absent in Asia except for four species in the Jordan Valley in the Middle East, one in Iran and three in India and Sri Lanka (Nelson, 2006). Europe, Australia, Antarctica, and North America north of the Rio Grande River drainage, do not have any native cichlids, although where environmental conditions are suitable, for example in Florida, Mexico (which also has several native species), Japan and northern Australia, feral populations of cichlids have become established as invasive species.
Cichlids are less commonly found in brackish and salt water habitats, though many species will tolerate brackish water for extended periods. Cichlasoma urophthalmus, for example, is equally at home in freshwater marshes and mangrove swamps, and can be found living and breeding in salt water environments such as the mangrove belts around barrier islands (Loiselle, 1994). Several species of tilapias (species of Tilapia, Sarotherodon, and Oreochromis) are euryhaline and can disperse along some brackish coastlines between rivers (Nelson, 2006). Only a few cichlids, however, are found primarily in brackish or salt water, most notably Etroplus maculatus, Etroplus suratensis, and Sarotherodon melanotheron (Schäfer, 2005).
[edit] Diet
Cichlids are astonishingly diverse in terms of diet. Many are primarily herbivores feeding on algae (e.g. Petrochromis) and plants (e.g. Etroplus suratensis) and small animals, particularly invertebrates, are only a small part of their diet. Some cichlids are detritivores and eat all types of organic material; among these species are the tilapiines of the genera Oreochromis, Sarotherodon, and Tilapia.
Other cichlids are predatory and eat little if any 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 is a specialised snail-eater, while Pungu maclareni feeds on sponges. A number of cichlids feed on other fish, either whole or in part. Crenicichla are stealth-predators that lunge at small fish that pass by their hiding places, while Rhamphochromis are open water pursuit predators that chase down their prey [3]. Paedophagous cichlids such as the Caprichromis species eat other species' eggs or young (in some cases ramming the heads of mouthbrooding species to force them to disgorge their young) (Konings, 2007; McKaye & Kocher, 1983; Ribbink & Ribbink, 1997; Wilhelm, 1980). Among the more unusual feeding strategies are those of Corematodus spp., Docimodus evelynae, Plecodus, Perissodus and Genyochromis species, which feed on scales and fins of other fishes, a behaviour known as lepidophagy (Eccles & Lewis, 1976; Nshombo, 1991; Trewavas, 1947), along with the death mimicking behaviour of Nimbochromis and Parachromis species, which lay motionless, luring small fish to their side prior to ambush (McKaye, 1981; Tobler, 2005).
[edit] Reproduction
[edit] Brood care
All species show some form of parental care for both eggs and larvae, often extended to free-swimming young until they are several weeks or months old. Species of this family have highly organized breeding activities (Nelson, 2006).
Parental care falls into one of four categories: substrate or open brooders, secretive cave brooders (also known as guarding speleophils) (Balon, 1975), and at least two types of mouthbrooding, ovophile mouthbrooding and larvophile mouthbrooding (Keenleyside, 1991).
Open or substrate brooding cichlids lay their eggs in the open on rocks, leaves or logs. Examples of open brooding cichlids include Pterophyllum, Symphysodon spp. and Anomalochromis thomasi. In general, brooding biparental substrate-brooding cichlids usually engage in differing roles with regard to protection and raising of the fry. Most commonly, the male parent patrols the pair's territory and repels intruders, while females more intensively tend the brood, fanning water over the eggs, removing infertile eggs and leading the school of fry while foraging. Despite this, both sexes are able to perform the full range of parenting behaviours (Keenleyside, 1991). 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. Communication between free-swimming fry and parents of both open and cave spawning cichlids has been observed for a number of cichlids in captivity and in the wild (Keenleyside, 1991). Frequently this communication is based on body movements, such as shaking and pelvic fin flicking (Keenleyside, 1991). In addition, parental substrate brooding cichlids assist in finding food resources for their fry. Parental behaviours such as leaf-turning, and fin-digging have been observed for a number of neotropical cichlid species (Keenleyside, 1991).
Communal parental care, where multiple monogamous pairs care for a mixed school of young have also been observed for a number of cichlid species, including Amphilophus citrinellus, Etroplus suratensis and Tilapia rendalli (McKaye & McKaye, 1977; Ribbink et al., 1981; Ward & Wyman, 1977). 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 [4].
Ovophile mouthbrooders incubate their eggs in their mouths as soon as they are laid, and frequently continue to brood free-swimming fry in their mouths for several weeks. Examples of ovophile mouthbrooding cichlids include many of the cichlids endemic to the Rift Valley lakes (Lake Malawi, Lake Tanganyika and Lake Victoria) in east Africa, e. g. Maylandia, Pseudotropheus and Tropheus along with some South American cichlids such as Geophagus steindachneri. Larvophile mouthbrooding species lay the eggs in the open, or in a cave and upon hatching take the larvae into the mouth. Examples include some variants of Geophagus altifrons, some Aequidens, Gymnogeophagus and Satanoperca species (Loiselle, 1994). Regardless of whether eggs or larvae are subject to mouthbrooding, the vast majority of mouthbrooding cichlids are maternal mouthbrooders, that is the female mouthbroods the young. In the eretmodine cichlids (genera Spathodus, Eretmodus and Tanganicodus), some Sarotherodon species, Chromidotilapia guntheri and some Aequidens species, however, mouthbrooding is practiced by both the male and the female (Coleman, 1999; Keenleyside, 1991; Loiselle, 1994). Paternal mouthbrooding, though rare, is also known to occur in the family eg. Sarotherodon melanotheron (Kishida & Specker, 2000). Mouthbrooding appears to have evolved independently in several groups of African cichlids (Nelson, 2006).
Several cichlids, including discus (Symphysodon spp.), some Amphilophus species, Etroplus and Uaru species are noted to feed their young with a skin secretion from mucous glands (Loiselle, 1994).
[edit] Mating system
Cichlids are either monogamous or polygamous in their mating system (Loiselle, 1994). The mating system of any given cichlid species is not consistently associated with the type of brood care the species employs. For example, although most monogamous cichlids are not mouthbrooding cichlids, Chromidotilapia, Gymnogeophagus, Spathodus and Tanganicodus are all monogamous mouthbrooders. In contrast, numerous open or cave spawning cichlids are polygamous, examples include Apistogramma, Lamprologus, Nannacara and Pelvicachromis (Loiselle, 1994; Martin & Taborsky, 1997).
[edit] Taxonomy
Kullander (1998) recognises eight subfamilies of cichlids: the Astronotinae, Cichlasomatinae, Cichlinae, Etroplinae, Geophaginae, Heterochromidinae, Pseudocrenilabrinae and Retroculinae. However, Nelson (2006) indicates that cichlid taxonomy is still greatly debated, and despite these attempts, classification of genera cannot yet be accurately 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 extant problems in cichlid taxonomy, Kullander published a phylogeny of the Cichlidae (details of which can be found here) in which the African genus Heterochromis ended up being placed phylogenetically within Neotropical cichlds, although later papers arrived at different conclusions. Other extant problems (mentioned in the following paragraph) centre upon the identity of the putative common ancestor for the Lake Victoria superflock, and the precise ancestral lineages of the Tanganyikan cichlids.
Streeman et al. (1998) provided comparisons between the phylogeny (from Stiassny, 1991) as determined using morphological characteristics, and two maximum-pasrimony bootstrap consensus trees based upon analyses of two different gene loci, along with majority-rule trees and other similar phylogenetic trees based upon assorted gene locus analyses. There are some extant differences between the assorted trees at the genus level that require resolution, though the consensus from the various nuclear and mitochondrial DNA analyses in this and other papers is that the Cichlidae as a family is monophyletic. Further insights into the attractiveness of cichlid taxonomy as a fertile area of research were given by Salzburger & Meyer (2004), in which the advances made in the analysis of the phylogeny of the Lake Victoria superflock (among other East African Cichlids) were discussed in depth.
One problem that resulted in a major upheaval of cichlid taxonomy was highlighted by Dr Humphrey Greenwood of the Natural History Museum, London, in a paper in 1977 (cited in TFH magazine, August 1977, with a follow up letter by Dr Greenwood in the November 1977 issue complaining about poor reportage of his work). Dentition (characteristics of tooth shape and arrangement) had been used prior to this date as classifying characteristics, which Greenwood demonstrated was invalid upon phylogenetic grounds because in many cichlid species, dentition is an environmentally plastic characteristic (tooth shape changes in numerous species with age, due to wear etc), and cannot be relied upon universally across the family as a diagnostic characteristic upon which to base phylogenetic judgements. It is in the light of this that cichlid taxonomy has undergone major revisions in the 30-plus years since, with the advent of genome sequencing and other technologies adding to the ever-growing body of data resulting in the still-fluid state of cichlid taxonomy at the genus level.
[edit] Genera
As of 2006, there were some 220 genera Fishbase:
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[edit] Dendrogram of Select Taxa
<==Cichlidae |--Cichla |--Astronotus ocellatus |--Hemichromis bimaculatus |--Aequidens latifrons |--Hemihaplochromis multicolor [=Haplochromis multicolor] |--Astatoreochromis alluaudi |--Labidochromis vellicans |--Genyochromis mento |--Labeotropheus fuelleborni |--Pterophyllum scalare |--*Ctenochromis pectoralis (Pfeffer 1893) [=Haplochromis pectoralis] |--Serranochromis |--Pharyngochromis darlingi |--Etroplus suratensis |--Symphysodon discus |--Petrotilapia tridentiger |--Pseudotropheus zebra |--Limnochromis permaxillaris |--Aulonocara nyassae |--Lethrinops brevis |--Docimodus johnstoni |--Rhamphochromis macrophthalmus |--Cyathochromis obliquidens |--Perissodus microlepis |--Schubotzia Boulenger 1914 | `--S. eduardiana Boulenger 1914 [=Haplochromis eduardiana] |--Lamprologus Schilthuis 1891 | `--L. lethops Roberts & Stewart 1976 |--Thoracochromis | |--T. mahagiensis | `--T. pharyngalis |--Yssichromis Greenwood 1980 | |--*Y. fusiformis (Greenwood & Gee 1969) [=Haplochromis fusiformis] | |--Y. laparogramma (Greenwood & Gee 1969) [=Haplochromis laparogramma] | `--Y. pappenheimi (Boulenger 1914) [=Haplochromis pappenheimi] |--Cichlasoma | |--C. bimaculatum | |--C. citrinellum | |--C. cutleri | |--C. cyanoguttatum | |--C. dovii | |--C. festae | |--C. nicaraguense | |--C. nigrofasciatum | `--C. octofasciatum |--Tilapia | |--T. bemini | |--T. esculenta | |--T. galilaea | |--T. karongae | |--T. leucosticta | |--T. lidole | |--T. macrochir | |--T. melanopleura | |--T. mossambica [=Oreochromis mossambicus] | |--T. natalensis | |--T. nilotica [=Oreochromis niloticus, Sarotherodon nilotica] | |--T. squamipinnis | |--T. variabilis | `--T. zilli [=Oreochromis zilli, Sarotherodon zilli] |--+--Enterochromis Greenwood 1980 | | |--*E. erythrocephalus (Greenwood & Gee 1969) [=Haplochromis erythrocephalus] | | |--E. cinctus (Greenwood & Gee 1969) [=Haplochromis cinctus] | | |--E. nigripinnis (Regan 1921) [=Haplochromis nigripinnis] | | `--E. paropius (Greenwood & Gee 1969) [=Haplochromis paropius] | `--+--Haplochromis | `--+--Xystichromis Greenwood 1980 | | |--*X. nuchisquamulatus (Hilgendorf 1888) (see below for synonymy) | | |--X. bayoni Boulenger 1911 (see below for synonymy) | | `--X. phytophagus (Greenwood 1966) [=Haplochromis phytophagus] | `--Neochromis Regan 1920 | |--N. nigricans (Boulenger 1906) (see below for synonymy) | |--N. fuscus (Regan 1925) [=Haplochromis fuscus] | `--N. serridens (Regan 1925) [=Haplochromis serridens] |--Astatotilapia Pellegrin 1903 | | i. s.: A. aeneocolor (Greenwood 1973) [=Haplochromis aeneocolor] | | A. desfontainesi | | ‘Haplochromis’ dolorosus | | A. eduardi (Regan 1921) (see below for synonymy) | | A. elegans (Trewavas 1933) [=Haplochromis elegans] | | A. engyostoma (Trewavas 1933) [=Haplochromis engyostoma] | | A. latifasciata (Regan 1926) [=Haplochromis latifasciatus] | | A. macropsoides (Greenwood 1973) [=Haplochromis macropsoides] | | A. melanopus (Regan 1922) [=Haplochromis melanopus] | | ‘Haplochromis’ nubilus | | A. oregosoma (Greenwood 1973) [=Haplochromis oregosoma] | | A. schubotziella (Greenwood 1973) [=Haplochromis schubotziellus] | | A. velifer (Trewavas 1933) [=Haplochromis velifer] | |--A. bloyeti [=Haplochromis bloyeti] | |--+--A. lacrimosa (Boulenger 1906) [=Haplochromis lacrimosus] | | |--A. macrops (Boulenger 1911) [=Haplochromis macrops] | | |--A. megalops (Greenwood & Gee 1969) [=Haplochromis megalops] | | `--A. piceata (Greenwood & Gee 1969) [=Haplochromis piceatus] | |--+--+--A. barbarae (Greenwood 1967) [=Haplochromis barbarae] | | | `--Lipochromis | | `--+--+--A. cinerea (Boulenger 1906) [=Haplochromis cinereus] | | | `--A. brownae (Greenwood 1962) [=Haplochromis brownae] | | `--+--‘Haplochromis’ apogonoides Greenwood 1967 | | `--A. martini (Boulenger 1906) [=Haplochromis martini] | `--+--A. pallida (Boulenger 1911) [=Tilapia pallida, Haplochromis pallidus] | `--Labrochromis Regan 1920 | | i. s.: ‘Tilapia’ adolphifrederici Blgr. 1914 [=Haplochromis adolphifrederici] | | L. mylergates (Greenwood & Barel 1978) [=Haplochromis mylergates] | | L. mylodon (Greenwood 1973) [=Haplochromis mylodon] | | ‘Haplochromis’ placodus Poll 1939 | | L. ptistes (Greenwood & Barel 1978) [=Haplochromis ptistes] | | L. teegelaari (Greenwood & Barel 1978) [=Haplochromis teegelaari] | |--L. humilior (Boulenger 1911) [=Haplochromis humilior] | `--+--*L. ishmaeli (Boulenger 1906) [=Haplochromis ishmaeli] | `--L. pharyngomylus (Regan 1929) [=Haplochromis pharyngomylus] |--Tropheus `--+--Gaurochromis Greenwood 1980 | |--G. (Gaurochromis) | | |--*G. (G.) empodisma (Greenwood 1960) [=Haplochromis empodisma] | | |--G. (G.) angustifrons (Boulenger 1914) [=Haplochromis angustifrons] | | `--G. (G.) simpsoni (Greenwood 1965) [=Haplochromis simpsoni] | `--G. (Mylacochromis Greenwood 1980) | `--G. (*M.) obtusidens (Trewavas 1928) [=Haplochromis obtusidens] `--+--+--Prognathochromis | `--+--Harpagochromis | `--Pyxichromis Greenwood 1980 | |--*P. parorthostoma (Greenwood 1967) [=Haplochromis parorthostoma] | `--P. orthostoma (Regan 1922) [=Haplochromis orthostoma] `--+--+--Allochromis Greenwood 1980 | | `--*A. welcommei (Greenwood 1966) [=Haplochromis welcommei] | `--Psammochromis Greenwood 1980 | | i. s.: P. cassius (Greenwood & Barel 1978) [=Haplochromis cassius] | | P. graueri (Boulenger 1914) [=Haplochromis graueri] | | P. schubotzi (Boulenger 1914) [=Haplochromis schubotzi] | |--P. acidens (Greenwood 1967) [=Haplochromis acidens] | `--+--P. aelocephalus (Greenwood 1959) [=Haplochromis aelocephalus] | `--+--*P. riponianus (Boulenger 1911) (see below for synonymy) | `--P. saxicola (Greenwood 1960) [=Haplochromis saxicola] `--+--+--Hoplotilapia Hilgendorf 1888 | | `--*H. retrodens (Hilgendorf 1888) [=Paratilapia retrodens] | `--Platytaeniodus Boulenger 1906 | `--*P. degeni Boulenger 1906 `--+--Macropleurodus Regan 1922 | `--M. bicolor (Boulenger 1906) [=Haplochromis bicolor] `--+--Ptyochromis Greenwood 1980 | |--+--*P. sauvagei (Pfeffer 1896) (see below for synonymy) | | `--P. annectens (Regan 1922) (see below for synonymy) | `--+--P. granti (Boulenger 1906) [=Haplochromis granti] | `--P. xenognathus (Greenwood 1957) [=Haplochromis xenognathus] `--Paralabidochromis Greenwood 1956 |--*P. victoriae Greenwood 1956 |--P. beadlei (Trewavas 1933) [=Haplochromis beadlei] |--P. chilotes (Boulenger 1911) [=Haplochromis chilotes] |--P. chromogynos (Greenwood 1959) [=Haplochromis chromogynos] |--P. crassilabris (Boulenger 1906) [=Haplochromis crassilabris] |--P. labiatus (Trewavas 1933) [=Haplochromis labiatus] |--P. paucidens (Regan 1921) [=Haplochromis paucidens] |--P. plagiodon (Regan & Trewavas 1928) [=Haplochromis plagiodon] |--‘Haplochromis’ theliodon Greenwood 1960 `--‘Haplochromis’ wittei Poll 1939
Astatotilapia eduardi (Regan 1921) [=Haplochromis eduardi; incl. H. vicarius Trewavas 1933]
Neochromis nigricans (Boulenger 1906) [=Haplochromis nigricans, Tilapia nigricans; incl. T. simotes Boulenger 1911, *Neochromis simotes]
*Psammochromis riponianus (Boulenger 1911) [=Pelmatochromis riponianus, Haplochromis riponianus]
Ptyochromis annectens (Regan 1922) [=Haplochromis annectens non Cyrtocara annectens Regan 1921, H. prodromus Trewavas 1935]
*Ptyochromis sauvagei (Pfeffer 1896) [=Ctenochromis sauvagei, Haplochromis sauvagei]
Xystichromis bayoni Boulenger 1911 non Haplochromis bayoni Boulenger 1909 [=Haplochromis niloticus Greenwood 1960]
*Xystichromis nuchisquamulatus (Hilgendorf 1888) [=Chromis nuchisquamulatus, Haplochromis nuchisquamulatus]
* Type species of genus indicated
[edit] References
Balon, E. K. 1975. Reproductive guilds of fishes: a proposal and definition Journal of the Fisheries Research Board of Canada 32: 821–864.
Beeching, S. C., B. A. Holt & M. P. Neiderer. 2002. Ontogeny of melanistic color pattern elements in the convict cichlid, Cichlasoma nigrofasciatum. Copeia 2002 (1): 199-203.
Bond, C. E. 1996. Biology of Fishes (2nd ed.) Saunders College Publishing: Fort Worth.
Boruchowitz, D. E. 2006. Guide to Cichlids. T.F.H. Publications.
Campbell, N. A. 1996. Biology (4th ed.) The Benjamin/Cummings Publishing Company, Inc.: Menlo Park (California).
Coleman, R. 1999. Mysterious mouthbrooders. Cichlid News January: 32–33.
Eccles, D.H., & D. S. C. Lewis. 1976. A taxonomic study of the genus Docimodus Boulenger (Pisces, Cichlidae) a group of fishes with unusual feeding habits from Lake Malawi. Zoological Journal of the Linnean Society 58: 165–172.
Gibbons, A. 1996. On the many origins of species. Science 273: 1496-1499.
Greenwood, P. H. 1974. The cichlid fishes of Lake Vistoria, East Africa: The biology and evolution of a species flock. Bulletin of the British Museum (Natural History): Zoology Suppl. 6: 1-134.
Greenwood, P. H. 1980. Towards a phyletic classification of the ‘genus’ Haplochromis (Pisces, Cichlidae) and related taxa. Part II; the species from Lakes Victoria, Nabugabo, Edward, George and Kivu. Bulletin of the Briitish Museum (Natural History): Zoology 39: 1-101.
Helfman, G., B. Collette & D. Facey. 1997. The Diversity of Fishes. Blackwell Publishing, Inc.
Jocqué, R. 2002. Genitalic polymorphism – a challenge for taxonomy. Journal of Arachnology 30 (2): 298-306.
Keenleyside, M. H. A. 1991. Parental care. In Cichlid Fishes: behaviour, ecology and evolution pp. 191-208. Chapman and Hall: London.
Kishida, M., & J. L. Specker. 2000. Paternal mouthbrooding in the black-chinned tilapia, Sarotherodon melanotheron (Pisces: Cichlidae): changes in gonadal steroids and potential for vitellogenin transfer to larvae. Hormones and Behavior 37: 40–48.
Klein, J., A. Sato, S. Nagl & C. O'hUigín. 1998. Molecular trans-species polymorphism. Annual Review of Ecology and Systematics 29: 1-21.
Konings, A. 2007. Paedophagy in Malawi cichlids. Cichlid News 16: 28–32.
Kornfield, I., & P. Smith. 2000. African cichlid fishes: model systems for evolutionary biology. Annual Review of Ecology and Systematics 31: 163.
Kullander, S.O. 1998. A phylogeny and classification of the South American Cichlidae (Teleostei: Perciformes). In Phylogeny and Classification of Neotropical Fishes (L. R. Malabarba, R. E. Reis, R. P. Vari, Z. M. Lucena & C. A. S. Lucena, eds.) pp. 461-198. EDIPUCRS: Porto Alegre.
Loiselle, P. V. 1994. The Cichlid Aquarium. Tetra Press.
[hhtp://dx.doi.org/10.1007/s002650050391 Martin, E., & M. Taborsky. 1997]. Alternative male mating acttics in a cichlid, Pelvicachromis pulcher: a comparison of reproductive effort and success. Behavioral Ecology and Sociobiology 41: 311–319.
Mayr, E. 1947. Ecological factors in speciation. Evolution 1: 263-288.
McKaye, K. R. 1981. Field observation on death feigning: a unique hunting behavior by the predatory cichlid, Haplochromis livingstoni, of Lake Malawi. Environmental Biology of Fishes 6: 361–365.
McKaye, K. R., & T. Kocher. 1983. Head ramming behaviour by three paedophagous cichlids in Lake Malawi, Africa. Animal Behaviour 31: 206.
[http://dx.doi.org/10.2307/2407533 McKaye, K. R., & N. M. McKaye. 1977. Communal care and kidnapping of young by parental cichlids. Evolution 31: 674–681.
Miller, S. A., & J. P. Harley. 1996. Zoology (3rd ed.) Wm. C. Brown Publishers: Dubuque (Iowa).
Nelson, J. S. 2006. Fishes of the World. John Wiley & Sons, Inc.
Nshombo, M. 1991. Occasional egg-eating by the scale-eater Plecodus straeleni (Cichlidae) of Lake Tanganyika. Environmental Biology of Fishes 31: 207–212.
Ribbink, A. J., A. C. Marsh & B. A. Marsh. 1981. Nest-building and communal care of young by Tilapia rendalli Dumeril (Pisces, Cichlidae) in Lake Malawi. Environmental Biology of Fishes 6: 219–222.
Ribbink, A.J., & A. C. Ribbink. 1997. Paedophagia among cichlid fishes of Lake Victoria and Lake Malawi/Nyasa. South African Journal of Science 93: 509–512.
Salzburger, W., & A. Meyer. 2004. The species flocks of East African cichlid fishes: recent advances in molecular phylogenetics and population genetics. Naturwissenschaften 91: 277–290.
Salzburger, W., T. Mack, E. Verheyen & A. Meyer. 2005. Out of Tanganyika: Genesis, explosive speciation, key-innovations and phylogeography of the haplochromine cichlid fishes. BMC Evolutionary Biology 5: 17.
Schäfer, F. 2005. Brackish-Water Fishes. Aqualog.
Snoeks, J. (ed.) 2004. The Cichlid Diversity of Lake Malawi/Nyasa/Niassa: identification, distribution and taxonomy. Cichlid Press.
Stiassny, M. L. J., & J. S. Jensen. 1987. Labroid intrarelationships revisited: morphological complexity, key innovations, and the study of comparative diversity. Bulletin of the Museum of Comparative Zoology, Harvard University 151: 269–319.
Stiassny, M., G. G. Teugels & C. D. Hopkins. 2007. The Fresh and Brackish Water Fishes of Lower Guinea, West-Central Africa, vol. 2. Musée Royal de l'Afrique Centrale.
Streelman, J. T., R. Zardoya, A. Meyer & S. A. Karl. 1998. Multilocus phylogeny of cichlid fishes (Pisces: Perciformes): evolutionary comparison of microsatellite and single-copy nuclear loci. Molecular Biology and Evolution 15 (7): 798–808.
Thinès, G., & G. Proudlove. 1986. Pisces. In Stygofauna Mundi: A Faunistic, Distributional, and Ecological Synthesis of the World Fauna inhabiting Subterranean Waters (including the Marine Interstitial) (L. Botosaneanu, ed.) pp. 709-733. E. J. Brill / Dr. W. Backhuys: Leiden.
Tobler, M. 2005. Feigning death in the Central American cichlid Parachromis friedrichsthalii. Journal of Fish Biology 66: 877.
Trewavas, E. 1947. An example of "mimicry" in fishes. Nature 160: 120.
Ward, J. A., & R. L. Wyman. 1977. Ethology and ecology of cichlid fishes of the genus Etroplus in Sri Lanka: preliminary findings. Environmental Biology of Fishes 2: 137–145.
10.1163/156853980X00528 Wilhelm, W. 1980. The disputed feeding behavior of a paedophagous haplochromine cichlid (Pisces) observed and discussed. Behaviour 74: 310.
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