Taxonomy & naming
Electrophorus voltai was described in 2019 by de Santana, Wosiacki, Crampton, Sabaj, Dillman, Castro e Castro Bastos & Vari, part of a landmark study that split the single, long-recognized "electric eel" (Electrophorus electricus) into three separate species using DNA, morphology and the distinct electric organ discharges of specimens across the Amazon and Guiana/Brazilian Shield river systems. The species epithet honours Alessandro Volta, the Italian physicist whose invention of the electric battery (the voltaic pile) was directly inspired by studies of electric fish; the genus name Electrophorus itself means "electricity bearer".
Electrophorus sits in the family Gymnotidae within the order Gymnotiformes, the New-World electric knifefishes — a group of scaleless, elongated fishes that swim on a single long fin and navigate largely by electric sense rather than sight. Its closest living relatives are the banded knifefishes of the genus Gymnotus, not true eels (order Anguilliformes), which the animal resembles only in body shape through convergent evolution. The type locality for E. voltai is the Ipitinga River near Almeirim, Pará, Brazil, with the holotype held at the Museu Paraense Emílio Goeldi. As with all valid names on this site, the Catalog of Fishes (Eschmeyer, CAS) is treated as the taxonomic authority.
Morphology
Electrophorus voltai has the classic gymnotiform silhouette: a long, cylindrical, scaleless body with no dorsal fin and no true tail fin, propelled instead by a long ribbon-like anal fin that runs along most of the ventral surface, letting the fish move forwards and backwards with equal ease. It is the largest member of its order, reaching roughly 67.5 in total length, and is built less for speed than for delivering a devastating jolt at close range.
Most of the body's interior is given over to specialised electric organs, which in Electrophorus produce two distinct types of discharge: low-voltage signals of only a few volts, used continuously for electrolocation — sensing obstacles, prey and other fish in dark or turbid water — and high-voltage pulses that can exceed 800 volts, deployed in short bursts to stun prey or repel a threat. In E. voltai a discharge of 860 V was recorded from a fish of about 48 in, the highest voltage ever measured from a living animal. The fish is also an obligate air-breather: its mouth is heavily vascularised and functions almost like a lung, and the fish must surface every few minutes to gulp air, which lets it survive in warm, poorly oxygenated backwaters where gill-breathing fish would struggle.
Habitat
Electrophorus voltai is a highland specialist, restricted to river systems draining the southern Brazilian Shield — principally clearwater and rocky, fast-flowing tributaries of the Tocantins–Araguaia basin, in contrast to its lowland relative E. varii and the more northerly E. electricus of the Guiana Shield. It favours upland stretches with rapids and stony substrate rather than the slow, silty channels typical of much of the Amazon basin.
Water in these habitats runs warm — around 86–88 °F has been recorded in rivers such as the Iriri — with a near-neutral to slightly acidic pH (roughly 6.5–7.0), low mineral content (conductivity under 30 µS/cm) and generally good dissolved oxygen for a highland river, although the species' air-breathing habit means it is well equipped to cope wherever oxygen runs low. Data on the full extent of its range remain sparse, reflecting how recently this species was recognised as distinct from the wider electric eel complex.
Feeding
Electrophorus voltai is a predator that hunts fish, and its high-voltage discharge is central to how it feeds: a burst of electricity can stun or immobilise prey at a distance, after which the eel simply approaches and swallows it whole. Documented prey includes small characins such as Poptella, Moenkhausia and Tetragonopterus, as well as armoured catfish like Megalechis thoracata, along with arthropods and incidental plant material.
What makes the species' feeding behaviour especially remarkable is cooperative hunting: groups of five to ten individuals have been observed herding shoals of small fish into a tight "prey ball" covering roughly 12 square metres of open water, then discharging simultaneously in coordinated high-voltage pulses to stun the entire group at once before feeding. This kind of group predation is exceptional among fishes and had not been documented in any electric fish before it was described in E. voltai.
Mating
As in other gymnotiforms, electric organ discharge is thought to play a role in courtship and communication in Electrophorus, with individuals able to signal identity, sex and condition through the character of their discharge. Beyond that general expectation, however, courtship behaviour in E. voltai specifically has not been documented in the literature reviewed here — the species was only recognised in 2019, and detailed behavioural studies are still limited.
What is better established comes from the wider genus: Electrophorus is understood to breed seasonally, with reproduction tied to the dry season when water levels drop and conditions favour nest building. Data on courtship specifically in E. voltai remain sparse, and this account does not extend beyond what can be confidently traced to the cited sources.
Breeding
Breeding in Electrophorus follows the unusual pattern seen across the family Gymnotidae, in which males provide direct parental care — a rarity among fishes. In the dry season, the male is understood to construct a foam nest from saliva and guard the eggs and the resulting shoal of larvae until they disperse, a mode presumed to apply to E. voltai on the basis of its close relatives, though detailed breeding accounts specific to this species are lacking.
Electrophorus voltai has essentially never been bred in captivity; specialised care of any kind is confined to a handful of public aquaria worldwide, and reproduction has not been documented outside the wild. This is a species to describe honestly as poorly studied in this respect rather than to over-specify — the safest statement is that its breeding biology is presumed similar to its congeners, with confirmation still lacking.
In the aquarium
Electrophorus voltai is not a home aquarium fish. It grows toward two metres in length, is an obligate air-breather that must have access to the surface at all times, and — most importantly — is capable of discharging over 800 volts, a shock that has been implicated in human fatalities from related electric eels and that no domestic setup can safely contain. Any keeping of this species belongs exclusively to large public aquaria and research institutions with the tank volume, life-support systems and safety protocols such an animal demands.
Where it is kept, husbandry follows the same broad principles as for scaleless gymnotiforms generally: warm, soft, near-neutral water, gentle flow, secure cover, and extreme caution with copper-based or otherwise harsh medications, to which scaleless fish are unusually sensitive. None of this should be read as an invitation to attempt keeping the species privately — it plainly cannot be done responsibly outside an institutional setting.
Conservation
Electrophorus voltai is assessed by the IUCN Red List as Least Concern, reflecting what is currently known of its distribution across upland tributaries of the Brazilian Shield, though as a species described only in 2019 its full range and population trends remain incompletely mapped.
As a highland specialist tied to clearwater, rocky river stretches, the species could in principle be vulnerable to the pressures affecting Amazonian headwaters generally — damming, mining-related mercury contamination, and deforestation-driven changes to water quality — but data specific to E. voltai's population trend are sparse, and this account does not go beyond the Least Concern assessment currently on record.