Maravillas Red Shiner (Cyprinella lutrensis ssp. blairi)
The Maravillas Red Shiner was restricted to the Garden Springs and the Pena Colorado Creek, which are a part of the Maravillas Creek drainage, a tributary of the Rio Grande in the Big Bend region of Texas, USA.
This subspecies reached a length of about 4,4 cm
The Maravillas Red Shiner disappeared in the late 1950s due to competition with introduced, invasive Plains Killifish (Fundulus zebrinus Jordan & Gilbert).
Some biologists consider the Maravillas Red Shiner synonymous with the nominate form.
Red Shiner (Cyprinella lutrensis (Baird & Girard)); nominate form
The Orontes Bream, aka. Long-spine Bream, described in 1843; it was restricted to Lake Amik in Turkey as well as some water bodies in the Ghab Plain in Syria, which both obtain their water from the Orontes River.
Lake Amik was drained in the 1940 to obtain land for growing cotton but also to eliminate malaria; and the swampy areas in the Ghab Plan were drained in the 1950s, more or less for the same reasons.
The Orontes Bream is now most likely completely extinct.
Depiction from: ‘M. Goren; L. Fishelson; E. Trewavas: The cyprinid fishes of Acanthobrama Heckel and related genera. Bulletin of the British Museum (Natural History) Zoology 24(6): 293-315. 1973’
The Trustees of the Natural History Museum, London
The Danube Delta Dwarf Goby is a very small freshwater goby that is only known from a single small lagoon south of the Danube Delta in Romania, where it inhabited shallow brackish and fresh water, usually less than 1 m deep.
The species reached a length of only about 3 cm; it was greyish colored and its body was covered with small blackish spots.
The Danube Delta Dwarf Goby was last seen in 1994, since then it is lost without any trace and appears to be extinct.
The Tecopa Pupfish was described in 1948, it was restricted to some outlets of the North- and South Tecopa Hot Springs in Inyo County, California, USA.
The two hot springs that this fish inhabited were very popular in the 1950s and 60s and were used for recreationally purposes; bathhouses were built, the spring pools were enlarged and their outflows were diverted which resulted in swifter currents which again caused the water temperatures downstream to rise above the level to which this pupfish was adapted.
All these modifications also allowed a subspecies closely related to this form, the Amargosa River Pupfish (Cyprinodon nevadensis ssp. armagosae Miller), to invade the Tecopa Pupfish’s habitat and to hybridize with it.
The last presumed Tecopa Pupfishs were recorded in 1966, but these, having ‘too small’ scales, may already have been hybrids.
The Presa Pupfish was described in 1993, when it was already extinct.
The species was restricted to small creeks and ditches around La Presa Spring near the city of Aramberri in Nuevo León in Mexico; all of these are now completely dry due to excessive pumping of groundwater for agricultural purposes.
The Presa Pupfish, which reached an rather impressive size for a pupfish of up to 7 cm, was last seen in 1988 and is now extinct.
 M. L. Lozano-Vilano; M. De La Maza-Beningnos: Diversity and status of Mexican killifishes. Journal of Fish Biology 90(1): 1-36. 2016
The Santa Cruz Pupfish, also known as Monkey Spring Pupfish, was endemic to the Santa Cruz River system in Santa Cruz County in Arizona, USA, where it apparently was restricted to the margins of an artifical pond fed by an irrigation canal from Monkey Spring.
The species reached a size of about 3,8 cm.
The Santa Cruz Pupfish disappeared around 1970, due to the introduction of Largemouth Basses (Micropterus salmoides (Lacépède)) for ‘sport’ fishing. The species was kept in captivity for some times but breeding efforts were unsuccessful so that the Santa Cruz Pupfish is now extinct.
This Plateau Chub was described in 1894, it inhabited freshwater channels in the Chalco – and the Xochimilco-Tláhuac area in the Valley of Mexico, a region that is no longer existent due to the unstoppable growth of Mexico City.
The species apparently disappeared at around 1954.
The Luhondo Yellowfish was described in 1937; it was endemic to Lake Luhondo in Rwanda and is only known from the type specimen.
The species started to disappear in the late 1930s after the introduction of cichlid species, including tilapias, into the lake, which outcompeted the native fish species.
Depiction from: ‘Keith Edward Banister: A revision of the large Barbus (Pisces, Cyprinidae) of east and central Africa. Studies on African Cyprinidae. Part II. Bulletin of the British Museum (Natural History) Zoology 26: 1-147. 1973’
Walker’s Toadfish was described in 1981; it is known only from the holotype that was found 1953 in the Panama Bay, Panama.
The type locality is considered to be in an eutrophic state due to ongoing pollution from agricultural- and livestock operations as well as from urban wastewaters from Panama City; Walker’s Toadfish might well be extinct now.
This is a quite enigmatic species, described in 1784, whose taxonomic status isn’t clear.
The May Trout is rather known from anecdotes about trouts that inhabited the deep parts of the lakes within the Danube basin in Austria, and which only in the month of May appeared in shallow waters to breed.
The status of this species, as said above, is far from being clarified, if it indeed was a distinct species it appears to be extinct now.
The Baolan Barbel, locally known as Baolan, was endemic to Lake Lanao on the island of Mindanao, Philippines, where it was said to inhabit deeper waters.
The species reached a length of about 11 cm.
The fish is known from only nine specimens, despite being one of the most highly esteemed for food and apparently the rarest and most difficult to obtain. It is said to have only been caught during the colder months, and only after a storm with the waves still running high.
The species was reportedly last caught in 1963 to 1964, it is now feared to be extinct.
The Graveche, also known as Kilch, Kleine Fera or Lake Geneva Whitefish was endemic to Lake Geneva, where it was formerly one of the most commonly caught species.
The species reached lengths of 25 to 32 cm, it lived mainly among or near the lake’s bottom where it fed on tiny to tiniest organisms.
Despite being one of the most common species of the lake, the species was already disappearing during the 19th century, so the catching size for this species in Switzerland was officially set to above 20 cm in 1887.
This effort, however, came too late, the Graveche disappeared completely and is now globally extinct.
The Lake Tota Feeler Fish is known from only ten specimens that were caught between 1942 and 1957 in the Lake Tota and is now considered extinct.
This about 14 cm long, incredibly ugly fish is unique among Pencil Catfishes in possessing remarkable rings of extensive adipose tissues surrounding its body, and giving it a somewhat large intestine-like appearance.
So far, nothing is known about its biology, the extinction was probably caused on the one hand by the introduction of the Rainbow Trout (Oncorhynchus mykiss (Walbaum)), and on the other hand by the subsidence of the water level due to seismic activities.
 Scott A. Schaefer; Luis Fernández: Redescription of the Pez Graso, Rhizosomichthys totae (Trichomycteridae), of Lago de Tota, Colombia, and Aspects of Cranial Osteology Revealed by Microtomography. Copeia 2009(3): 510-522. 2009
The Dragon Lake is a 2,25 km² resp. 225 ha large lake in British Columbia, it is a popular destination for anglers and well known for its large rainbow trouts (Oncorhynchus mykiss (Walbaum)) – however, that wasn’t always so.
The lake was once the home for two sympatric whitefish species – both species have never been described, and both species fell victim to a so called ‘lake rehabilitation’ in the year 1956.
The term ‘rehabilitaion’ disguises the pervert idea, to reshape a lake appropriate for so called game fishes by using insecticides like rotenone and toxaphene, both of which are simply deadly for fishes, to exterminate all living things, so that, later, when the poisons have vanished from the water of the now dead lake, the desired game fishes can be introduced – in the case of the Dragon Lake rainbow trouts.
The Dragon Lake Whitefish was similar to the Lake Whitefish (Coregonus clupaeformis (Mitchill)), but differed from this species in the number of its gill rakers.
This species, which locally is known as Dipura or Pait, was endemic to Lake Lanao on the island of Mindanao, Philippines.
The species reached a length of about 11 cm.
The species was reportedly last caught in 1982, all subsequent surveys failed to record it and it is now feared to be extinct.
The causes for the extinction of so many endemic fish species from Lake Lanao are the excessive exploitation of fish, which is the main diet for the increasing human population in the area; the traditional fishing methods having been replaced by dynamite fishing, which simply destroys and kills everything, and by the use of several poisons.
This species was described in 1924; it was endemic to Lake Lanao on the island of Mindanao, Philippines.
In the 1960s, the Tank Goby (Glossogobius giuris (F. Hamilton)), a predatory fish species was accidently introduced to the lake, leading to the extinction of several endemic fish species. However, overfishing, rampant use of destructive fishing methods (dynamite fishing), and unsustainable fishing practices certainly played their part too.
The Bitungu was last recorded in 1975 and is now extinct.
Described in 1963, the Utah Lake Sculpin was restricted to Lake Utah, a shallow freshwater lake in Utah, USA
The species is thought to have died out due to a severe drought in the 1920s and 1930s that led to a rapid fall of the water levels, followed by a cold winters in which the lake was freezing resulting in a congestion of the remaining fish in a few open spots, resulting in food shortages and lack of oxygen.
However, during the same years, the water quality had apparently significantly worsen due to the entry of waste water by agriculture etc..
The Mexican Chub is one of three known species in this genus, all of them are now extinct due to habitat loss.
This Mexican Chub was described in 1955, it inhabited canals and streams in the Valley of Mexico, a plateau in central Mexico that now is nearly completely overbuilt by Mexico City, one of the largest cities on the planet.
The species died out at around 1983 as a result of the complete drying of the water bodies in the valley due to the withdrawal of water by the agriculture and the unstoppable growth of the city and its suburbs.
The Las Vegas Dace was described in 1984, it was declared extinct in 1986, only two years later.
The Las Vegas Valley in Nevada, USA originally was formed by a river, this river, however, started to disappear at 4000 to 1000 BCE., leaving behind only three springs and becoming merely a dry wash.
The last Las Vegas Daces were cought in 1940 (but were not recognized as being distinct), they apparently survived in one of the springs and outflows until 1955 to 1957, but disappeared sometimes before 1967.
The creek that formerly held the three springs is now obviously completely dry.
 Robert Rush Miller: Rhinichthys deaconi, a new species of dace (Pisces: Cyprinidae) from southern Nevada. Occasional Papers of the Museum of Zoology University of Michigan 707: 1-21. 1984
This species was described in 1988, it was restricted to the coastal plains near Rio São João, Rio de Janeiro in southeast Brazil.
Cruz’s Pearlfish reached a length of only about 3 to 4 cm.
The genus Notholebias contains at least four species, one of which is already extinct, the remaining three are close to extinction.
 Wilson J. E. M. Costa; Pedro F. Amorim: Delimitation of cryptic species of Notholebias, a genus of seasonal miniature killifishes threatened with extinction from the Atlantic Forest of south-eastern Brazil (Cyprinodontiformes: Rivulidae). Ichthyological Exploration of Freshwaters 24(1): 63-72. 2013
The San Marcos Mosquitofish was described in 1969.
The species was restricted to the San Marcos Spring, a large vegetated spring, and its effluent in Hays County, Texas, USA.
The San Marcos Mosquitofish reached a length of about 4 cm, the species was live bearing, a large female could give birth to up to 60 young.
The species disappeared due to a mix of influences, including the pollution of the water by sprayed herbicides along the San Marcos River, and the introduction of another Gambusia species, the Western Mosquitofish (Gambusia affinis (Baird & Girard)), with which it hybridized.
The last pure San Marcos Mosquitofish were seen in 1983.