Nothobranchius, known as nothobranchs or simply nothos, is a genus of small, freshwater killifish, classified in the family Nothobranchiidaevan der Laan, R., Eschmeyer, W.N. & Fricke, R. (2014): Family-group names of Recent fishes. Zootaxa, 3882 (2): 1–230. in the order Cyprinodontiformes. There are about a hundred species in the genus, many with very small distributions. They are primarily native to East Africa from Sudan to northern South Africa, whereas a dozen species are found in the upper Congo River Basin, with the greatest species richness being in Tanzania.
Nothobranchius typically inhabit ephemeral pools that are filled only during the monsoon season, and show extreme life-history adaptations to survive the dry season. When their habitats dry up, the adult fish die and the eggs survive encased in the clay during the dry season. The embryos survive the dry season by entering diapause, facilitated by their specialized eggs that have a very hard chorion and are resistant to desiccation and hypoxia.Alexander Dorn, Zuzana Musilová, Matthias Platzer, Kathrin Reichwald and Alessandro Celler (2014) The strange case of East African annual fishes: aridification correlates with diversification for a savannah aquatic group? BMC Evolutionary Biology 14:210. DOI: 10.1186/s12862-014-0210-3 These species reach maturity very quickly once diapause is broken and have a very short life span; one species, Nothobranchius furzeri, reaches maturity in 17 days and seldom lives beyond 6 months.
Etymology The genus name Nothobranchius comes from Ancient Greek νόθος (nóthos), meaning 'crossbred', and βράγχιος (bránkhios), meaning 'with gills'.
Species
There are 102 recognized species in this genus:
Nothobranchius albertinensis Nagy, Watters & Bellstedt, 2020 Nothobranchius albimarginatus Watters, Wildekamp & Cooper, 1998 Nothobranchius angelae Watters, Nagy & Bellstedt, 2019 Nothobranchius annectens Watters, Wildekamp & Cooper, 1998 Nothobranchius attenboroughi Nagy, Watters & Bellstedt, 2020 Nothobranchius balamaensis Bragança & Chakona, 2022 Nothobranchius bellemansi Valdesalici, 2014Valdesalici, S. (2014): Nothobranchius bellemansi and Nothobranchius occultus (Cyprinodontiformes: Nothobranchiidae) two new annual killifish from Sudan. Killi-Data Series, 2014: 4-19. Nothobranchius bojiensis Wildekamp & Haas, 1992 (Boji Plains nothobranch) Nothobranchius boklundi Valdesalici, 2010 Nothobranchius brieni Poll, 1938 Nothobranchius capriviensis Watters, Wildekamp & Shidlovskiy, 2015 (Caprivi nothobranch)Watters, B.R., Wildekamp, R.H. & Shidlovskiy, K.M. (2015): Description and biogeography of Nothobranchius capriviensis, a new species of annual killifish from the Zambezi Region of Namibia (Cyprinodontiformes: Nothobranchiidae). Journal of the American Killifish Association, 47 (4-6): 97-133. Nothobranchius cardinalis Watters, Cooper & Wildekamp, 2008 (cardinal nothobranch) Nothobranchius chochamandai Nagy, 2014Nagy, B. (2014): Nothobranchius chochamandai, a new species of annual killifish from the Luapula drainage, Democratic Republic of Congo (Cyprinodontiformes: Nothobranchiidae). Ichthyological Exploration of Freshwaters, 25 (2): 167-183. Nothobranchius cooperi Nagy, Watters & Bellstedt, 2017 Nothobranchius derhami Valdesalici & Amato, 2019 Nothobranchius ditte Nagy, 2018 Nothobranchius dubieensis Nagy, 2025 Nagy, B. (2025). Review of Cyprinodontiform Fishes in the Upper Congo Drainage with Descriptions of Four New Species of Seasonal Nothobranchius (Nothobranchiidae) and a New Species of ‘Lacustricola’ Lampeye (Procatopodidae) in South-Eastern DR Congo. Ecology and Diversity, 2 (10006): 1-43. Nothobranchius eggersi Seegers, 1982 Nothobranchius elongatus Wildekamp, 1982 (elongate nothobranch) Nothobranchius elucens Nagy, 2021 Nothobranchius fasciatus Wildekamp & Haas, 1992 Nothobranchius flagrans Nagy, 2014 Nagy, B. (2014): Nothobranchius flagrans, a new species of annual killifish from the Lufira drainage, Democratic Republic of Congo (Cyprinodontiformes: Nothobranchiidae). Ichthyological Exploration of Freshwaters, 25 (3): 259-276. Nothobranchius flammicomantis Wildekamp, Watters & Sainthouse, 1998 Nothobranchius foerschi Wildekamp & Berkenkamp, 1979 Nothobranchius furzeri Jubb, 1971 (turquoise killifish) Nothobranchius fuscotaeniatus Seegers, 1997 Nothobranchius geminus Wildekamp, Watters & Sainthouse, 2002 Nothobranchius guentheri (Pfeffer, 1893) (red-tail nothobranch) Nothobranchius hassoni Valdesalici & Wildekamp, 2004 Nothobranchius hengstleri Valdesalici, 2007 Nothobranchius hoermanni Nagy, Watters & Bellstedt, 2020 Nothobranchius insularis Costa, 2017Costa, W.J.E.M. (2017): Redescription of Nothobranchius lucius and description of a new species from Mafia Island, eastern Tanzania (Cyprinodontiformes, Aplocheilidae). Zoosystematics and Evolution, 93 (1): 35-44. Nothobranchius interruptus Wildekamp & Berkenkamp, 1979 (Kikambala nothobranchius) Nothobranchius iridescens Nagy, 2025 Nothobranchius itigiensis Nagy, Watters & Bellstedt, 2020 Nothobranchius ivanovae Valdesalici, 2012Valdesalici, S. (2012): Nothobranchius kardashevi and Nothobranchius ivanovae (Cyprinodontiformes: Nothobranchiidae): two new annual killifishes from the Katuma River drainage, western Tanzania. aqua, International Journal of Ichthyology, 18 (4): 191-198. Nothobranchius janpapi Wildekamp, 1977 Nothobranchius jubbi Wildekamp & Berkenkamp, 1979 Nothobranchius kadleci Reichard, 2010 Nothobranchius kafuensis Wildekamp & Rosenstock, 1989 (Kafue killifish) Nothobranchius kardashevi Valdesalici, 2012 Nothobranchius katemomandai Nagy, 2025 Nothobranchius kilomberoensis Wildekamp, Watters & Sainthouse, 2002 Nothobranchius kirki Jubb, 1969 (Red-fin nothobranch) Nothobranchius korthausae Meinken, 1973 Nothobranchius krammeri Valdesalici & Hengstler, 2008 Nothobranchius krysanovi Shidlovskiy, Watters & Wildekamp, 2010 Nothobranchius kwalensis W. J. E. M. Costa, 2019 Nothobranchius lourensi Wildekamp, 1977 Nothobranchius lucius Wildekamp, Shidlovskiy & Watters, 2009 Nothobranchius luekei Seegers, 1984 Nothobranchius makondorum Wildekamp, Shidlovskiy & Watters, 2009 Nothobranchius malaissei Wildekamp, 1978 Nothobranchius marmoreus Nagy, 2025 Nothobranchius matanduensis Watters, Nagy & Bellstedt, 2020 Nothobranchius melanospilus (Pfeffer, 1896) (black-spotted nothobranch) Nothobranchius microlepis (Vinciguerra, 1897) (small-scaled nothobranch) Nothobranchius milvertzi Nagy, 2014Nagy, B. (2014): Nothobranchius milvertzi, a new species of killifish from the Lushiba Marsh in the Lake Mweru drainage, Zambia (Teleostei: Cyprinodontiformes: Nothobranchiidae). Ichthyological Exploration of Freshwaters, 24 (4): 347-360. Nothobranchius mkuziensis (Fowler, 1934) Nothobranchius moameensis Nagy, Watters & Bellstedt, 2020 Nothobranchius neumanni (Hilgendorf, 1905) Nothobranchius niassa Valdesalici, Bills, Dorn, Reichwald & Cellerino, 2012Valdesalici, S., Bills, R., Dorn, A., Reichwald, K. & Cellerino, A. (2012): Nothobranchius niassa (Cyprinodontiformes: Nothobranchiidae), a new species of annual killifish from northern Mozambique. Ichthyological Exploration of Freshwaters, 23 (1): 19-28. Nothobranchius nikiforovi Nagy, Watters & Raspopova, 2021 Nothobranchius nubaensis Valdesalici, Bellemans, Kardashev & Golubtsov, 2009 Nothobranchius occultus Valdesalici, 2014 Nothobranchius ocellatus (Seegers, 1985) Nothobranchius oestergaardi Valdesalici & Amato, 2011 Nothobranchius orthonotus (Peters, 1844) (spotted killifish) Nothobranchius ottoschmidti Watters, Nagy & Bellstedt, 2019 Nothobranchius palmqvisti (Lönnberg, 1907) Nothobranchius patrizii (Vinciguerra, 1927) (blue nothobranch) Nothobranchius pienaari Shidlovskiy, Watters & Wildekamp, 2010 Nothobranchius polli Wildekamp, 1978 Nothobranchius poppi Nagy, Chocha Manda & Vreven, 2016Nagy, B., Chocha Mandala, A. & Vreven, E.J.W.M.N. (2016). Nothobranchius poppi, a new species of seasonal killifish (Cyprinodontiformes: Nothobranchiidae) from ephemeral wetlands of the lower Luapula River floodplain (upper Congo drainage: DR Congo). Ichthyological Exploration of Freshwaters, IEF-1204: 1–12. Nothobranchius prognathus Costa, 2019 Nothobranchius rachovii Ahl, 1926 (blue-fin nothobranch) Nothobranchius robustus Ahl, 1935 (red victoria nothobranch) Nothobranchius rosenstocki Valdesalici & Wildekamp, 2005 Nothobranchius rubripinnis Seegers, 1986 Nothobranchius rubroreticulatus Blache & Miton, 1960 Nothobranchius rungwaensis Watters, Nagy & Bellstedt, 2019 Nothobranchius ruudwildekampi Costa, 2009 Nothobranchius sagittae Wildekamp, Watters & Shidlovskiy, 2014Wildekamp, R.H., Watters, B.R. & Shidlovskiy, K.M. (2014): Review of the Nothobranchius neumanni species group with descriptions of three new species from Tanzania (Cyprinodontiformes: Nothobranchiidae). Journal of the American Killifish Association, 47 (1): 2-30. Nothobranchius sainthousei Nagy, Cotterill & Bellstedt, 2016Nagy, B., Cotterill, F.P.D. & Bellstedt, D.U. (2016): Nothobranchius sainthousei, a new species of annual killifish from the Luapula River drainage in northern Zambia (Teleostei: Cyprinodontiformes). Ichthyological Exploration of Freshwaters, 27 (3): 233-254. Nothobranchius seegersi Valdesalici & Kardashev, 2011 Nothobranchius serengetiensis Wildekamp, Watters & Shidlovskiy, 2014 Nothobranchius skeltoni Watters, Nagy & Bellstedt, 2019 Nothobranchius sonjae Watters, Nagy & Bellstedt, 2019 Nothobranchius steinforti Wildekamp, 1977 Nothobranchius streltsovi Valdesalici (sv), 2016Valdesalici, S. (2016): Nothobranchius streltsovi, a new species of annual killifish with two male colour morphs from the Malagarasi drainage, central Tanzania (Teleostei: Cyprinodontiformes: Nothobranchiidae). Ichthyological Exploration of Freshwaters, 27 (2): 153-161. Nothobranchius sylvaticus Nagy, Bellstedt & Luke, 2025Bellstedt, D. U., B. Nagy, P. D. W. van der Merwe, F. P. D. Cotterill, Q. Luke & B. R. Watters. (2025). The description of a critically endangered new species of seasonal killifish, Nothobranchius sylvaticus (Cyprinodontiformes: Nothobranchiidae), a relict species from an East African forest refugium in south-eastern Kenya. Zootaxa, 5601 (1): 086–108.
Nothobranchius symoensi Wildekamp, 1978 Nothobranchius taeniopygus Hilgendorf, 1891 (striped nothobranch) Nothobranchius taiti Nagy, 2019 Nothobranchius torgashevi Valdesalici, 2015Valdesalici, S. (2015): Nothobranchius torgashevi (Cyprinodontiformes: Nothobranchiidae) a new species of annual killifish with two male colour morphs from the Lake Eyasi Basin, Central Tanzania. Killi-Data Series, 2015: 17-30. Nothobranchius ugandensis Wildekamp, 1994 (Uganda nothobranch) Nothobranchius usanguensis Wildekamp, Watters & Shidlovskiy, 2014 Nothobranchius venustus Nagy, Watters & Bellstedt, 2020 Nothobranchius virgatus Chambers, 1984 Nothobranchius vosseleri Ahl, 1924 (Pangani nothobranch) Nothobranchius wattersi Ng'oma, Valdesalici, Reichwald & Cellerino, 2013Ng'oma, E., Valdesalici, S., Reichwald, K. & Cellerino, A. (2013): Genetic and morphological studies of Nothobranchius (Cyprinodontiformes) from Malawi with description of Nothobranchius wattersi sp. nov. Journal of Fish Biology, 82 (1): 165–188. Nothobranchius willerti Wildekamp, 1992 (Mnanzini nothobranch)
References