Updated 30 Sept. 2024
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Nakedback Knifefishes
Subfamily GYMNOTINAE Rafinesque 1815
Gymnotus Linnaeus 1758 gymnós (Gr. γυμνός), bare or naked; notus, from nṓtos (Gr. νῶτος), back, referring to absence of dorsal fin (a trait common to all knifefishes)
Subgenus Lamontianus Craig, Kim, Tagliacollo & Albert 2019 UNAVAILABLE; PUBLISHED ELECTRONICALLY WITHOUT ZOOBANK REGISTRATION –anus (L.), belonging to: Francesca Raymond La Monte (1895–1982), Assistant Curator of Ichthyology, American Museum of Natural History, for her contributions to gymnotiform taxonomy and ichthyology as a whole [“Lamontiana” would have been a grammatically preferable spelling]
Subgenus Pantherus Craig, Kim, Tagliacollo & Albert 2019 UNAVAILABLE; PUBLISHED ELECTRONICALLY WITHOUT ZOOBANK REGISTRATION derived from the name of the jaguar Panthera onca, following G. pantherinus, the type of this proposed subgenus
Subgenus Tigre Craig, Kim, Tagliacollo & Albert 2019 UNAVAILABLE; PUBLISHED ELECTRONICALLY WITHOUT ZOOBANK REGISTRATION tautonymous with G. tigre, the type of this proposed subgenus
Subgenus Tigrinus Craig, Kim, Tagliacollo & Albert 2019 UNAVAILABLE; PUBLISHED ELECTRONICALLY WITHOUT ZOOBANK REGISTRATION name derived from the Northern Tiger Cat Leopardus tigrinus; “Introducing this name, in combination with the subgenera Tigre and Pantherus, continues the convention of naming gymnotids for felids, which are often similarly nocturnal, predatory and banded or spotted”
Subgenus Tijax Craig, Kim, Tagliacollo & Albert 2019 UNAVAILABLE; PUBLISHED ELECTRONICALLY WITHOUT ZOOBANK REGISTRATION Mayan word (and astrological sign) meaning “knife” (as in knifefish); “The Mayan civilization occupied Central America, to which the Gymnotine subgenus is endemic, for almost four thousand years and made numerous cultural and technological advancements, including the only pre-Columbian writing system developed in the Americas”
Gymnotus anguillaris Hoedeman 1962 Latin for eel-like, referring to the long, “eel-like configuration” of its body compared with G. carapo
Gymnotus arapaima Albert & Crampton 2001 named for Arapaima gigas (Arapaimidae), which it resembles in having an elongate and slightly depressed head
Gymnotus arapiuns Kim, Crampton & Albert 2020 named for the rio Arapiuns, a blackwater river and tributary of the rio Tapajós in Pará, Brazil, where this knifefish occurs
Gymnotus ardilai Maldonado-Ocampo & Albert 2004 in honor of Carlos A. Ardila Rodriguez (b. 1950), President of the Colombian Ichthyological Association (ACICTIOS), for contributions to the knowledge of Colombian ichthyology
Gymnotus aripuana Kim, Crampton & Albert 2020 named for the rio Aripuanã in Mato Grosso, Brazil, where this knifefish occurs
Gymnotus bahianus Campos-da-Paz & Costa 1996 –anus (L.), belonging to: coastal drainages of Bahia, Brazil, where it is endemic
Gymnotus capanema Milhomem, Crampton, Pierczeka, Shetka, Silva & Nagamachi 2012 named for the municipality of Capanema, Pará, Brazil, type locality
Gymnotus capitimaculatus Rangel-Pereira 2014 capitis (L.), of the head; maculatus (L.), spotted (author says blotchy), referring to a pair of blotches on ventral portion of head
Gymnotus carapo Linnaeus 1758 local Brazilian name for knifefishes
Gymnotus carapo australis Craig, Crampton & Albert 2017 Latin for southern, known from southern humid Neotropics of Uruguay and Argentina, the most southernly subspecies
Gymnotus carapo caatingaensis Craig, Crampton & Albert 2017 –ensis, Latin suffix denoting place: Caatinga ecoregion of northeastern Brazil, where it occurs
Gymnotus carapo madeirensis Craig, Crampton & Albert 2017 –ensis, Latin suffix denoting place: upper Río Madeira basin of Bolivia and Peru, where it occurs
Gymnotus carapo occidentalis Craig, Crampton & Albert 2017 Latin for western, known from western Amazon basin of Peru (and elsewhere), the most westernly subspecies
Gymnotus carapo orientalis Craig, Crampton & Albert 2017 Latin for eastern, known from eastern Amazon basin of Brazil (and elsewhere, but not the most easternly subspecies, which is G. c. caatingaensis)
Gymnotus carapo septentrionalis Craig, Crampton & Albert 2017 Latin for northern, known from Orinoco basin (Colombia, Venezuela) and Trinidad, the most northernly subspecies
Gymnotus cataniapo Mago-Leccia 1994 named for the Río Cataniapo (Amazonas, Venezuela), where most specimens were collected
Gymnotus chaviro Maxime & Albert 2009 common name for Gymnotus among the Asheninka indigenous people of Peru, where it occurs
Gymnotus chimarrao Cognato, Richer-de-Forges, Albert & Crampton 2008 named for chimarrão, traditional mate tea (Ilex paraguariensis) of Rio Grande do Sul, Brazil (where this knifefish occurs), referring to its olive-green ground coloration, similar to the color of dried tea leaves (see G. cuia and Brachyhypopomus bombilla [Hypopomidae] for other mate-related knifefish names)
Gymnotus choco Albert, Crampton & Maldonado-Ocampo 2003 named for the Chocó region of the Pacific slope of Colombia, where it occurs
Gymnotus coatesi La Monte 1935 in honor of Christopher W. Coates (1899–1974), Curator (later Director), New York Aquarium, and student of electric fishes, who provided holotype (Coates was also the first to use captive electric eels to power light bulbs, a staple exhibit at public aquaria worldwide)
Gymnotus coropinae Hoedeman 1962 of Coropina Creek, Suriname, type locality
Gymnotus cuia Craig, Malabarba, Crampton & Albert 2018 named for the cuia gourd used to drink traditional mate popular through this fish’s range, referring to its especially deep body and head (and continuing a tradition of mate-related names in gymnotiform taxonomy; see G. chimarrao and Brachyhypopomus bombilla [Hypopomidae])
Gymnotus curupira Crampton, Thorsen & Albert 2005 named for Igarapé Curupira, a forest stream near Tefé, Amazonas, Brazil, type locality (the Curupira is a mythical spirit of the Amazon rain forest)
Gymnotus cylindricus La Monte 1935 Latin for cylindrical, referring to its body shape
Gymnotus darwini Campos-da-Paz & de Santana 2019 in honor of English naturalist Charles Darwin (1809–1882), “well known from his extensive and genial contribution to the study of evolution through natural selection,” and because holotype and a number of paratypes were collected at the Refúgio Ecológico Charles Darwin in Igarassu, Pernambuco, Brazil, where Darwin himself visited in August 1836 while aboard the H.M.S. Beagle
Gymnotus diamantinensis Campos-da-Paz 2002 –ensis, Latin suffix denoting place: municipality of Diamantino, Mato Grosso, Brazil, type locality
Gymnotus esmeraldas Albert & Crampton 2003 named for the Río Esmeraldas drainage, Ecuador, type locality
Gymnotus eyra Craig, Correa-Roldán, Ortega, Crampton & Albert 2018 local (Peru) name for red form of the jaguarundi, Herpailurus yagouaroundi, continuing a convention of naming Gymnotus species after felids (onca, pantherinus, tigre) due to their shared nocturnal, predatory, banded or spotted attributes
Gymnotus henni Albert, Crampton & Maldonado-Ocampo 2003 in honor of Carl Eigenmann’s student (and successor) Arthur Wilbur Henn (1890–1959), a “pioneer” in Neotropical ichthyology, who collected holotype in 1913
Gymnotus inaequilabiatus (Valenciennes 1839) inequalis (L), unequal, uneven or unlike; labiatus (L.), lipped, referring to lower jaw projecting beyond the upper, with thick lips on the former and none on the latter
Gymnotus interruptus Rangel-Pereira 2012 Latin for interrupted, referring to pale interbands, anterior to vertical through first ventral lateral line ramus, ventrally and/or dorsally fragmented (=interrupted), allowing for the union of adjacent dark bands
Gymnotus javari Albert, Crampton & Hagedorn 2003 named for the Río Yavari (or Javarí), Loreto Department, Peru, type locality
Gymnotus jonasi Albert & Crampton 2001 in honor of naturalist Jonas Alves de Oliveira, Mamirauá Sustainable Development Reserve (Amazonas, Brazil), where this knifefish occurs
Gymnotus maculosus Albert & Miller 1995 Latin for spotted, referring to numerous small brown spots, varying in size from two to four times eye diameter, distributed over most of its body
Gymnotus mamiraua Albert & Crampton 2001 named for the Mamirauá lake system and Mamirauá Sustainable Development Reserve (Amazonas, Brazil), type locality
Gymnotus melanopleura Albert & Crampton 2001 mélanos (Gr. μέλανος), genitive of mélas (μέλας), black; pleurá (Gr. πλευρά), side, referring to dark bands along lateral body surface
Gymnotus obscurus Crampton, Thorsen & Albert 2005 Latin for dark, referring to its predominantly dark coloration
Gymnotus omarorum Richer-de-Forges, Crampton & Albert 2009 -orum (L.), commemorative suffix, plural: in honor of Omar Macadar, a neurologist, and Omar Trujillo-Cenoz (b. 1933), a neuroanatomist, both from Uruguay and both described as “pioneers” in the anatomical and physiological study of electrogenesis in Gymnotus
Gymnotus onca Albert & Crampton 2001 named for the jaguar Panthera onca, referring to its characteristic color pattern of broad irregular dark pigment blotches
Gymnotus panamensis Albert & Crampton 2003 –ensis, Latin suffix denoting place: Panama, where it is endemic to the Cricamola River drainage
Gymnotus pantanal Fernandes, Albert, Daniel-Silva, Lopes, Crampton & Almeida-Toledo 2005 named for the Pantanal Matogrossense of Brazil, the hydrological region where type locality (Rio Miranda, Mato Grosso do Sul) is situated
Gymnotus pantherinus (Steindachner 1908) Latin for panther-like, presumably referring to irregularly shaped spots and dots that are sometimes connected in a zigzag and “halfbow-like” manner (translation)
Gymnotus paraguensis Albert & Crampton 2003 –ensis, Latin suffix denoting place: Paraguay River basin, Brazil and Paraguay, where it is endemic
Gymnotus pedanopterus Mago-Leccia 1994 pedanós (Gr. πεδανός), low-growing or short; pterus, from pterón (Gr. πτερόν) or ptéryx (πτέρυξ), fin, referring to the shortness of its anal-fin rays (although these rays are not mentioned in the description)
Gymnotus refugio Giora & Malabarba 2016 Portuguese for sanctuary, referring to its abundance only in two conservation areas of Rio Grande do Sul, Brazil: Refúgio da Vida Silvestre Banhado dos Pachecos, and Parque Estadual de Itapeva
Gymnotus riberalta Craig, Correa-Roldán, Ortega, Crampton & Albert 2018 named for Riberalta, Beni Department, Bolivia, type locality
Gymnotus stenoleucus Mago-Leccia 1994 sténos (Gr. στένος), narrow; leukós (Gr. λευκός), white, referring to narrow pale bands on anterior third of body
Gymnotus sylvius Albert & Fernandes-Matioli 1999 Latin for Silvio, named for Silvio de Almeida Toledo Filho, a “pioneer” in the electrobiology of Gymnotus from southeastern Brazil; also alludes to sylva (L.), wood or forest, referring to the Atlantic rainforest where this species dwells
Gymnotus tigre Albert & Crampton 2003 Portuguese for tiger, based in its common name in the local aquarium trade, referring to its tiger-like markings
Gymnotus tiquie Maxime, Lima & Albert 2011 named for the rio Tiquié, upper Rio Negro basin, Brazil, where this species is known only from small tributaries
Gymnotus ucamara Crampton, Lovejoy & Albert 2003 named for the Ucamara Depression, a geological term for the low-lying region between the lower reaches of the Ucayali and Marañon rivers of Peru (where it occurs), caused by subsidence in the Upper Amazon foreland basin
Gymnotus varzea Crampton, Thorsen & Albert 2005 named for the várzea (freshwater swamp forest) floodplains near Tefé, Amazonas, Brazil, where this knifefish occurs
Electric Eels
Subfamily ELECTROPHORINAE Gill 1872
Electrophorus Gill 1864 electro-, combining form of electricus; phorus, from phoreús (Gr. φορεύς), bearer or carrier, referring to its ability to generate a powerful electric shock (may also allude to an 18th-century manual capacitive generator of the same name)
Electrophorus electricus (Linnaeus 1766) Neo-Latin for “of amber,” referring to amber’s attractive properties, later applied to objects capable of attracting “light bodies” (e.g., bits of paper) when excited by friction, and then applied even later to the cause (electricity) rather than the property of the attraction, referring to this fish’s ability to generate a powerful electric shock
Electrophorus multivalvulus Nakashima 1941 multi– (L.), many; valvulus (L.), having folding doors, referring to a series of irregular lichen-like skin folds inside the mouth; Nakashima guessed that their function was related to the generation of electricity, but they actually serve as lungs, allowing electric eels to absorb oxygen from atmospheric air [sometimes misspelled as multivalvulatus]
Electrophorus varii de Santana, Wosiacki, Crampton, Sabaj, Dillman, Mendes-Júnior & Castro e Castro 2019 in honor of Richard P. Vari (1949–2016), National Museum of Natural History, Smithsonian Institution (Washington, D.C., USA), for his contributions to ichthyology [possibly a junior synonym of E. multivalvulus]
Electrophorus voltai de Santana, Wosiacki, Crampton, Sabaj, Dillman, Castro e Castro, Bastos & Vari 2019 in honor of Alessandro Giuseppe Antonio Anastasio Volta (1745–1827), inventor of electric battery and for whom the “volt” is named (with a discharge of 860 V, this species is the strongest living bioelectricity generator known)