Taxonomy & naming
Epiplatys ruhkopfi was formally described by Hans-O. Berkenkamp and Volker Etzel in 1990. Prior to its elevation to species rank, the fish had circulated in the hobby and literature as a subspecies or population of Epiplatys fasciolatus, the banded panchax — a widely distributed West African panchax whose complex has generated repeated taxonomic revision. The Catalog of Fishes (Eschmeyer, CAS) records the valid name as Epiplatys ruhkopfi Berkenkamp & Etzel, 1990, with the type locality in central Liberia.
The genus Epiplatys belongs to the family Nothobranchiidae and encompasses the Old World panchax group of killifishes, all of which are surface-oriented, plant-spawning non-annuals native to sub-Saharan Africa. Unlike the annual killifishes of the related genera Nothobranchius and Fundulopanchax, Epiplatys species inhabit permanent or semi-permanent waters and do not produce diapausing eggs buried in substrate. E. ruhkopfi is placed in the broad 'Panchax group' assemblage within Epiplatys sensu lato.
The authority year 1990 is supported by FishBase and the British Killifish Association's Killi-News journal index, which documents coverage of the species including an article by Adrian Burge (p. 43) citing Berkenkamp & Etzel as the authority. A note in the etyfish.org etymology dictionary records 1980 in one reference, but 1990 is the year consistent with the formal species description as recognised by FishBase and the Catalog of Fishes.
Morphology
Epiplatys ruhkopfi is a slender, elongate killifish reaching approximately 3 in total length according to FishBase, with aquarium-kept individuals typically measuring 3 in. The body plan is typical of surface-dwelling panchax: a flat-topped head with an upturned, terminal mouth adapted for taking prey at the water surface or in the upper water column, a streamlined mid-section, and a rounded to slightly pointed caudal fin.
Colouration in males is striking for the genus, featuring the banded or reticulated flank pattern characteristic of the fasciolatus complex, with contrasting colour accents in the unpaired fins. Females are drabber and more uniformly coloured, lacking the extended fin rays and vivid fin markings of males. Precise colour descriptions from type-locality wild fish are not fully documented in available sources, but the general pattern aligns with closely related fasciolatus complex members.
Sexual dimorphism is moderate and consistent with the genus: males are more intensely coloured, carry elongated dorsal and anal fin rays, and are typically slimmer in body profile. Females are plumper when gravid, with visible egg mass in the abdomen.
Habitat
The native range of Epiplatys ruhkopfi is central Liberia, placing it firmly within the Upper Guinea Forest ecoregion — one of Africa's most biodiverse and most threatened rainforest zones. Like other Liberian Epiplatys, the species is associated with the shaded, forest-margin waters of small streams, pools, and swampy areas within intact or near-intact lowland tropical forest. These habitats are characterised by low light levels due to dense canopy cover, soft and acidic water with low mineral content, and abundant leaf litter and submerged vegetation.
Aquarium literature records optimal water parameters of pH 5–6 and general hardness 2–8 GH, KH 0–3, and temperature 72–79 °F. These figures are consistent with the soft, moderately acidic waters typical of Upper Guinea forest streams and are in line with conditions reported for closely related West African forest panchax species. FishBase notes a central temperature of approximately 72 °F.
The species is a surface-oriented to mid-water dweller, typically found in the upper half of the water column where it hunts small invertebrates and insect prey. Dense floating or rooted vegetation and shaded conditions are characteristic features of its natural microhabitat.
Feeding
Epiplatys ruhkopfi is an insectivore and micro-predator in the wild, taking small invertebrates, insect larvae, terrestrial insects falling to the water surface, and other suitably sized prey encountered in the upper water column and at the surface film. The upturned mouth is a structural adaptation for surface feeding, and the fish is well-suited to ambush or interception of prey at or near the water surface.
In the aquarium, the species accepts a varied diet of small live and frozen foods — Drosophila and other small flies, bloodworm, Artemia, Tubifex, small aquatic invertebrates — as well as appropriately sized dried foods. Live and frozen foods are preferred and important for maintaining condition and inducing breeding readiness. Very large or hard-shelled prey items should be avoided given the relatively modest size of the fish.
Mating
Epiplatys ruhkopfi is a non-annual killifish and a plant spawner — it inhabits permanent or near-permanent water bodies and produces adhesive eggs that are laid on fine-leaved plants, submerged roots, moss, or spawning mops near the surface or in mid-water, rather than burying eggs in substrate as annual species do. Eggs develop continuously in water without diapause and are not dependent on a dry season or substrate incubation period.
Mating behaviour follows the pattern typical of the genus: the male courts the female with fin displays and lateral posturing, and the pair position themselves together among vegetation or a spawning mop to deposit a small number of eggs — usually one to a few at a time — over an extended period of days to weeks. The male is active in initiating and driving spawning but is not aggressive enough toward the female to require separation in a well-planted tank. Spawning productivity is relatively modest per session compared with annual species, but the pair spawn repeatedly over a long productive lifespan.
Breeding
In captivity, Epiplatys ruhkopfi is best spawned in a small, densely planted aquarium or a species tank furnished with fine-leaved plants (Java moss, Ceratopteris, floating Salvinia) and wool or nylon spawning mops. A pair or a group with one male to two or three females is typical. Water conditions for spawning should replicate the soft, slightly acidic native habitat: pH 5.5–6.5, GH 2–6, and temperature 72–77 °F.
Eggs are adhesive and relatively large for the genus, and are deposited individually or in small clusters on plant leaves or mop fibres. Incubation at 72–75 °F takes approximately two to three weeks, the fry hatch as small but free-swimming individuals capable of taking Artemia nauplii and micro-worm from the outset. Adults will readily consume eggs and small fry if not removed; the standard approach is either to remove the spawning mop or plant material with eggs to a separate hatching vessel, or to maintain a heavily planted setup where fry can hide until large enough to be safe.
The species is relatively long-lived for a killifish — Garnelio aquarium sources record a lifespan of approximately four to five years under good conditions, substantially longer than annual species and reflecting its non-diapausing biology. This longevity makes it a rewarding and long-term commitment for the specialist keeper.
In the aquarium
Epiplatys ruhkopfi is a specialist fish suited to the dedicated killifish keeper rather than a general community aquarium. Its water chemistry requirements — soft, acidic water at pH 5–6, low hardness, temperature 72–79 °F — place it outside the range comfortable for many commonly kept tropical fish, and it is best housed in a species or near-species setup where these parameters can be maintained consistently. A covered aquarium of at least 31.5 in length (as recommended in aquarium literature) with subdued lighting, dense planting, and dark substrate will show the fish to best advantage and encourage natural behaviour.
Tankmates, if kept, should be peaceful, of similar size, and tolerant of the same water conditions. Avoid boisterous or fin-nipping species. A pair or a small group is the recommended social unit; multiple males may compete, so sufficient space and visual barriers are important if more than one male is kept.
The species is considered moderately demanding by killifish standards, primarily due to its water chemistry requirements and its origin in intact forest habitat. It does not tolerate poor water quality or fluctuating parameters well. Careful attention to regular water changes with appropriately soft and acidic water, good filtration without strong current, and a varied live or frozen food diet will maintain the fish in good condition. Its four-to-five-year lifespan is a significant appeal for keepers who prefer not to cycle through short-lived annuals annually.
Conservation
The IUCN Red List assesses Epiplatys ruhkopfi as Endangered (EN), a status that reflects the extreme pressure on its native Liberian rainforest habitat. Liberia holds one of the last substantial remnants of the Upper Guinea Forest — a global biodiversity hotspot — but has experienced severe deforestation driven by logging, agricultural expansion, artisanal mining, and civil conflict over recent decades. The small streams, pools, and swampy forest habitats on which this species depends are directly threatened by the loss of surrounding tree cover, which raises water temperatures, increases siltation, and disrupts the hydrological conditions that maintain permanent forest pools.
As a species with a restricted range concentrated in central Liberia, E. ruhkopfi has little capacity to buffer habitat loss through range expansion. It is not known to have populations outside its native forest zone, and there are no formally protected areas reliably covering its core habitat. The IUCN status change documents from the 2019–2020 assessment cycle confirm the current Endangered listing.
The species has been maintained in European killifish hobby collections, particularly within the Deutsche Killifisch Gemeinschaft and British Killifish Association networks, which provides some insurance against total extinction of captive-held lineages. Wild collection history is documented, though current collection activity and the availability of wild-caught stock are not consistent. Conservation of intact Liberian lowland forest is the primary requirement for the long-term survival of this and many other forest-endemic species in the Upper Guinea region.