37-502: Many, see text Haplochromis is a ray-finned fish genus in the family Cichlidae . It has been used as the default " wastebin taxon " for Pseudocrenilabrinae cichlids of the East African Rift , and as such became the "largest" fish "genus". Many of these cichlids are popular aquarium fishes; like similar Haplochromini they are known as "haplos" , "happies" or "haps" among aquarium enthusiasts. The genus
74-565: A database covering forms of aquatic life other than finfish. This resulted, in 2006, in the birth of SeaLifeBase . The long-term goal of SeaLifeBase is to develop an information system modelled on FishBase, but including all forms of aquatic life, both marine and freshwater, apart from the finfish which FishBase specialises in. Altogether, there are about 300,000 known species in this category. As awareness of FishBase has grown among fish specialists, it has attracted over 2,480 contributors and collaborators. Since 2000 FishBase has been supervised by
111-487: A few years before their demise, and additional ones were only known or suspected to exist, but never properly studied or described. While the stocks of those species that survived are in many cases recovering, the lake ecosystem has changed irrevocably. The entire trophic web has been observed to be upset. But still, evolution runs its course: those Lake Victoria Haplochromis species that still exist are in many cases adapting to new food sources, and in time, speciation
148-459: A free-swimming larval stage. However other patterns of ontogeny exist, with one of the commonest being sequential hermaphroditism . In most cases this involves protogyny , fish starting life as females and converting to males at some stage, triggered by some internal or external factor. Protandry , where a fish converts from male to female, is much less common than protogyny. Most families use external rather than internal fertilization . Of
185-742: A trait still present in Holostei ( bowfins and gars ). In some fish like the arapaima , the swim bladder has been modified for breathing air again, and in other lineages it have been completely lost. The teleosts have urinary and reproductive tracts that are fully separated, while the Chondrostei have common urogenital ducts, and partially connected ducts are found in Cladistia and Holostei. Ray-finned fishes have many different types of scales ; but all teleosts have leptoid scales . The outer part of these scales fan out with bony ridges, while
222-587: Is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of skin supported by radially extended thin bony spines called lepidotrichia , as opposed to the bulkier, fleshy lobed fins of the sister class Sarcopterygii (lobe-finned fish). Resembling folding fans , the actinopterygian fins can easily change shape and wetted area , providing superior thrust-to-weight ratios per movement compared to sarcopterygian and chondrichthyian fins. The fin rays attach directly to
259-552: Is a global species database of fish species (specifically finfish ). It is the largest and most extensively accessed online database on adult finfish on the web. Over time it has "evolved into a dynamic and versatile ecological tool" that is widely cited in scholarly publications. FishBase provides comprehensive species data, including information on taxonomy , geographical distribution, biometrics and morphology , behaviour and habitats, ecology and population dynamics as well as reproductive, metabolic and genetic data. There
296-570: Is access to tools such as trophic pyramids , identification keys , biogeographical modelling and fishery statistics and there are direct species level links to information in other databases such as LarvalBase , GenBank , the IUCN Red List and the Catalog of Fishes . As of February 2024 , FishBase included descriptions of 35,600 species and subspecies, with 329,500 common names , 64,000 pictures, and references to 61,700 works in
333-545: Is divided into the infraclasses Holostei and Teleostei . During the Mesozoic ( Triassic , Jurassic , Cretaceous ) and Cenozoic the teleosts in particular diversified widely. As a result, 96% of living fish species are teleosts (40% of all fish species belong to the teleost subgroup Acanthomorpha ), while all other groups of actinopterygians represent depauperate lineages. The classification of ray-finned fishes can be summarized as follows: The cladogram below shows
370-686: Is hardly surprising that the genus has a large number of junior synonyms . Most referred to small or monotypic genera that were once considered distinct, but are now included in Haplochromis again, if only to wait for a major review of their status. Synonyms are: Sometimes other genera listed above are also synonymized. Ray-finned fish Actinopterygii ( / ˌ æ k t ɪ n ɒ p t ə ˈ r ɪ dʒ i aɪ / ; from actino- 'having rays' and Ancient Greek πτέρυξ (ptérux) 'wing, fins'), members of which are known as ray-finned fish or actinopterygians ,
407-482: Is highly doubtful, as they may just be distinct lineages of Haplochromis or other haplochromines. That nonwithstanding, Haplochromini genera to which some former "Haplochromis" have been removed are in particular: Some other Pseudocrenilabrinae were also – mainly by early authors – included in Haplochromis , though they are not members of its tribe . These are: With all the taxonomic and systematic confusion affecting Haplochromis and its allies, it
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#1732775515451444-420: Is likely to set in and produce a new adaptive radiation of these fishes. Until then, however, the ecological balance of the lake is still on the brink, and many of the cichlids that survived the peak population of Lates are still critically endangered and close to extinction. Haplochromis is the type genus of the tribe Haplochromini . Most of the tribe's members were at one time or another included in
481-432: Is relatively rare and is found in about 6% of living teleost species; male care is far more common than female care. Male territoriality "preadapts" a species for evolving male parental care. There are a few examples of fish that self-fertilise. The mangrove rivulus is an amphibious, simultaneous hermaphrodite, producing both eggs and spawn and having internal fertilisation. This mode of reproduction may be related to
518-506: The Cyprinidae (in goldfish and common carp as recently as 14 million years ago). Ray-finned fish vary in size and shape, in their feeding specializations, and in the number and arrangement of their ray-fins. In nearly all ray-finned fish, the sexes are separate, and in most species the females spawn eggs that are fertilized externally, typically with the male inseminating the eggs after they are laid. Development then proceeds with
555-592: The deep sea to subterranean waters to the highest mountain streams . Extant species can range in size from Paedocypris , at 8 mm (0.3 in); to the massive ocean sunfish , at 2,300 kg (5,070 lb); and to the giant oarfish , at 11 m (36 ft). The largest ever known ray-finned fish, the extinct Leedsichthys from the Jurassic , has been estimated to have grown to 16.5 m (54 ft). Ray-finned fishes occur in many variant forms. The main features of typical ray-finned fish are shown in
592-488: The oviparous teleosts, most (79%) do not provide parental care. Viviparity , ovoviviparity , or some form of parental care for eggs, whether by the male, the female, or both parents is seen in a significant fraction (21%) of the 422 teleost families; no care is likely the ancestral condition. The oldest case of viviparity in ray-finned fish is found in Middle Triassic species of † Saurichthys . Viviparity
629-575: The scientific literature . The site has about 700,000 visits per month. The origins of FishBase go back to the 1970s, when the fisheries scientist Daniel Pauly found himself struggling to test a hypothesis on how the growing ability of fish was affected by the size of their gills. Hypotheses, such as this one, could be tested only if large amounts of empirical data were available. At the time, fisheries management used analytical models which required estimates for fish growth and mortality . It can be difficult for fishery scientists and managers to get
666-663: The sister lineage of all other actinopterygians, the Acipenseriformes (sturgeons and paddlefishes) are the sister lineage of Neopterygii, and Holostei (bowfin and gars) are the sister lineage of teleosts. The Elopomorpha ( eels and tarpons ) appear to be the most basal teleosts. The earliest known fossil actinopterygian is Andreolepis hedei , dating back 420 million years ( Late Silurian ), remains of which have been found in Russia , Sweden , and Estonia . Crown group actinopterygians most likely originated near
703-938: The Devonian-Carboniferous boundary. The earliest fossil relatives of modern teleosts are from the Triassic period ( Prohalecites , Pholidophorus ), although it is suspected that teleosts originated already during the Paleozoic Era . The listing below is a summary of all extinct (indicated by a dagger , †) and living groups of Actinopterygii with their respective taxonomic rank . The taxonomy follows Phylogenetic Classification of Bony Fishes with notes when this differs from Nelson, ITIS and FishBase and extinct groups from Van der Laan 2016 and Xu 2021. [REDACTED] [REDACTED] [REDACTED] [REDACTED] [REDACTED] [REDACTED] [REDACTED] FishBase FishBase
740-402: The adjacent diagram. The swim bladder is a more derived structure and used for buoyancy . Except from the bichirs , which just like the lungs of lobe-finned fish have retained the ancestral condition of ventral budding from the foregut , the swim bladder in ray-finned fishes derives from a dorsal bud above the foregut. In early forms the swim bladder could still be used for breathing,
777-689: The beginnings of a software database along these lines was encoded in 1988. This database, initially confined to tropical fish, became the prototype for FishBase. FishBase was subsequently extended to cover all finfish , and was launched on the Web in August 1996. It is now the largest and most accessed online database for fish in the world. In 1995 the first CD-ROM was released as "FishBase 100". Subsequent CDs have been released annually. The software runs on Microsoft Access which operates only on Microsoft Windows . FishBase covers adult finfish, but does not detail
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#1732775515451814-463: The bichirs and holosteans (bowfin and gars) in having gone through a whole-genome duplication ( paleopolyploidy ). The WGD is estimated to have happened about 320 million years ago in the teleosts, which on average has retained about 17% of the gene duplicates, and around 180 (124–225) million years ago in the chondrosteans. It has since happened again in some teleost lineages, like Salmonidae (80–100 million years ago) and several times independently within
851-475: The data available in the published literature into some central and easily accessed repository. Such a database would be particularly useful if the data has also been standardised and validated. This would mean that when scientists or managers need to test a new hypothesis, the available data will already be there in a validated and accessible form, and there will be no need to create a new dataset and then have to validate it. Pauly recruited Rainer Froese , and
888-706: The different actinopterygian clades (in millions of years , mya) are from Near et al., 2012. Jaw-less fishes ( hagfish , lampreys ) [REDACTED] Cartilaginous fishes ( sharks , rays , ratfish ) [REDACTED] Coelacanths [REDACTED] Lungfish [REDACTED] Amphibians [REDACTED] Mammals [REDACTED] Sauropsids ( reptiles , birds ) [REDACTED] Polypteriformes ( bichirs , reedfishes ) [REDACTED] Acipenseriformes ( sturgeons , paddlefishes ) [REDACTED] Teleostei [REDACTED] Amiiformes ( bowfins ) [REDACTED] Lepisosteiformes ( gars ) [REDACTED] The polypterids (bichirs and reedfish) are
925-402: The early and juvenile stages of fish. In 1999 a complementary database, called LarvalBase , went online under the supervision of Bernd Ueberschär. It covers ichthyoplankton and the juvenile stage of fishes, with detailed data on fish eggs and larvae , fish identification , as well as data relevant to the rearing of young fish in aquaculture . Given FishBase's success, there was a demand for
962-761: The entire tribe remains badly resolved, however, and further changes in taxonomy are likely in the future. In particular, between Haplochromis , Astatotilapia and Thoracochromis , species have been moved to and from over the years. The habit of Pseudocrenilabrinae to hybridize is hampering molecular phylogenetic studies based on mtDNA alone, while trophic morphs of a single species may appear to be distinct "species" if they are not phylogenetically studied. Several proposed genera are again included in Haplochromis at present, but it cannot be ruled out that some of these will eventually be recognized as valid again. There are currently 229 recognized species in this genus: These populations are typically referred to by
999-432: The fish's habit of spending long periods out of water in the mangrove forests it inhabits. Males are occasionally produced at temperatures below 19 °C (66 °F) and can fertilise eggs that are then spawned by the female. This maintains genetic variability in a species that is otherwise highly inbred. Actinopterygii is divided into the subclasses Cladistia , Chondrostei and Neopterygii . The Neopterygii , in turn,
1036-428: The information they need on the species that concern them, because the relevant facts can be scattered across and buried in numerous journal articles, reports, newsletters and other sources. It can be particularly difficult for people in developing countries who need such information. Pauly believed that the only practical way fisheries managers could access the volume of data they needed was to assemble and consolidate all
1073-438: The inner part is crossed with fibrous connective tissue. Leptoid scales are thinner and more transparent than other types of scales, and lack the hardened enamel - or dentine -like layers found in the scales of many other fish. Unlike ganoid scales , which are found in non-teleost actinopterygians, new scales are added in concentric layers as the fish grows. Teleosts and chondrosteans (sturgeons and paddlefish) also differ from
1110-466: The main clades of living actinopterygians and their evolutionary relationships to other extant groups of fishes and the four-limbed vertebrates ( tetrapods ). The latter include mostly terrestrial species but also groups that became secondarily aquatic (e.g. whales and dolphins ). Tetrapods evolved from a group of bony fish during the Devonian period . Approximate divergence dates for
1147-404: The names they have in the aquarium fish trade. A number of them are likely to represent undescribed distinct species; others might just be subspecies or color morphs . Whether they all belong in Haplochromis is, of course, doubtful. Some of these populations are: Among other genera of Haplochromini that were formerly included here, many are small or monotypic . The distinctness of these
Haplochromis - Misplaced Pages Continue
1184-413: The present genus, but in many cases this was only temporary. Around the year 1900, as well 100 years later, the trend was to split up the genus; especially in the mid-20th century, on the other hand, most authors lumped any and all Haplochromini that were not conspicuously distinct in the type genus. While a number of African Rift Valley cichlids are certainly very close relatives of H. obliquidens ,
1221-494: The proximal or basal skeletal elements, the radials, which represent the articulation between these fins and the internal skeleton (e.g., pelvic and pectoral girdles). The vast majority of actinopterygians are teleosts . By species count, they dominate the subphylum Vertebrata , and constitute nearly 99% of the over 30,000 extant species of fish . They are the most abundant nektonic aquatic animals and are ubiquitous throughout freshwater and marine environments from
1258-538: The smaller cichlids were fair game for the huge carnivorous Lates . The Nile tilapia ( Oreochromis niloticus ), an adaptable generalist , was also introduced and competed with the often specialized endemic cichlids of the lake for food and other resources. When the Nile perch stocks finally declined again in the late 1980s, an estimated 200 Haplochromini species (mostly Haplochromis ) may have become extinct – many of these had only been scientifically described
1295-466: The type species of the present genus, it is not very clear where to draw the boundary of Haplochromis with regard to its relatives. Still, several genera are now recognized as distinct by many authors and scientific databases, such as FishBase (see below ); in particular the Haplochromini from Lake Tanganyika and Lake Malawi are usually removed from Haplochromis . The genus delimitation in
1332-423: Was abolished. As the years went by, other genera of (mostly) Haplochromini were lumped with and split again from Haplochromis , and the final delimitation of the clade around H. obliquidens is not yet done. The introduction of Nile perch ( Lates niloticus ) to Lake Victoria after 1954 severely upset the lake's ecosystem . By the late 1970s, the perch's population was approaching carrying capacity , and
1369-403: Was established by F.M. Hilgendorf in 1888. It was originally conceived as a subgenus of A.C.L.G. Günther 's "Chromis" , at that time an even larger "wastebin genus" for Pseudocrenilabrinae cichlids. The type species of Hilgendorf was H. obliquidens . "Chromis" of Günther turned out to be a junior homonym of G. Cuvier 's ocean fish genus Chromis , already established in 1814, and
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