Taxonomy & naming
Scriptaphyosemion guignardi was originally described by Arnoult and Doumenc in 1972, with later revisionary work by Romand in 1981 and 1982 contributing synonym Aphyosemion nigrifluvi (Romand, 1982), which is now treated as a junior synonym under the valid name. Eschmeyer's Catalog of Fishes (Fricke, Eschmeyer & Fong) records the valid combination as Scriptaphyosemion guignardi (Arnoult & Doumenc, 1972).
The genus Scriptaphyosemion was erected to accommodate a group of West African killifishes that share a distinctive fin and coloration pattern separating them from the more broadly circumscribed Aphyosemion. The group spans the humid forest and forest-savanna transition zone from Sierra Leone through Guinea and Senegal into The Gambia and western Mali, occupying a cluster of river basins that drain independently to the Atlantic. A Mamou population from the Mamou region of Guinea is recognized in the hobbyist literature as Scriptaphyosemion guignardi mamou, though this subspecific designation has not been formally validated in the primary ichthyological literature and should be used with caution.
Morphology
Scriptaphyosemion guignardi is a slender-bodied killifish reaching approximately 2.5 in total length (FishBase), though most individuals in the hobby are somewhat smaller, with adult males commonly measuring around 2 in. The body is laterally compressed and elongate in the typical Scriptaphyosemion manner, with a slightly upturned mouth suited to surface-feeding.
Sexual dichromatism is pronounced. Males show a bronzy or golden-brown dorsal surface that transitions to bright bluish-green sides, the flanks decorated with rows of iridescent dots arranged in a chevron or zigzag pattern. Dorsal, caudal, and anal fins carry red spotting or patterning on a greenish-blue base. Females are considerably plainer: the body is olive-brown with scattered red dots, the fins are yellowish, and the overall effect is cryptic. This dimorphism is typical of the genus and allows confident sex identification from an early age.
Habitat
The species occupies the Konkouré, Kolenté, Corubal, and Little Scarcies river systems in Guinea and Sierra Leone, the Gambia River of Senegal and The Gambia, and the Bani River in Mali — a distribution that spans several independent Atlantic-draining catchments in the West African forest and forest-savanna mosaic. Within these basins it is a lowland fish, found in quiet brooks, slow-moving streams, swampy backwaters, seasonally flooded pools, marshes, and the weedy marginal zones of small rivers.
Water chemistry across this range is soft and often slightly acidic, reflecting the tannin-staining of drainage through laterite soils and decaying leaf litter. Aquarium sources record a pH of 5.0–7.0 and general hardness in the range of 5–12 dH, with temperatures typically between 70–79 °F. Heavily vegetated or root-strewn habitats with reduced light are characteristic; the fish is rarely found in fast-flowing or exposed water.
Feeding
Scriptaphyosemion guignardi is an omnivore with a predatory bias, taking small invertebrates as its primary prey in the wild. The natural diet consists principally of aquatic and terrestrial insects, small crustaceans, worms, and other invertebrates encountered at or near the water surface and in the upper water column.
In the aquarium the species is straightforward to feed. It accepts live and frozen foods readily — daphnia, cyclops, mosquito larvae, bloodworm, and artemia are all reported as suitable staples — and can be trained onto high-quality dried foods over time. Because of its small mouth, food particle size matters: larger items such as whole bloodworm or adult artemia are more appropriate than oversized pellets. Frequent small meals maintain the condition and coloration of males better than infrequent large ones.
Mating
Scriptaphyosemion guignardi is a non-annual killifish and a plant or mop spawner, reproducing in a fundamentally different mode from the annual soil-burying killies that dominate the hobby's popular imagination. The species inhabits permanent or near-permanent water and does not produce diapausing eggs; instead, pairs deposit small numbers of adhesive eggs on fine-leaved vegetation, floating java moss, or spawning mops over an extended period rather than in a single explosive event.
Males court females with lateral displays emphasizing their iridescent flank coloration and fin ornamentation. Spawning occurs during close proximity among vegetation near the surface or substrate, with eggs attached individually to plant material or mop fibres. Each spawning session yields relatively few eggs — typically 10–20 per day — with a pair continuing to produce eggs over a period of several weeks. This trickle-spawning strategy differs markedly from the large clutches typical of annual species.
Breeding
Because eggs are produced continuously rather than in a mass clutch, the most practical aquarium breeding strategy is to leave a conditioned pair or trio (one male, two females) in a well-planted or mop-furnished tank and remove eggs or fry periodically rather than separating the parents. Slightly acidic water (pH 5.5–6.5) and dim lighting help reduce stress and encourage consistent spawning activity. A small sponge filter provides gentle circulation without risking fry losses to an intake.
Eggs incubate in water at ambient temperature with no diapause period; at 73–77 °F hatching occurs in approximately 12 days. Newly hatched fry are very small and require infusoria or commercial micro-food as first nutrition before graduating to microworm and newly hatched brine shrimp nauplii after a few days. The species is relatively long-lived for a killifish, with a reported lifespan of up to three years under good conditions. Adults do not show strong predatory interest in well-grown fry, though eggs and very young larvae are at some risk if adults are not well fed.
In the aquarium
Scriptaphyosemion guignardi is considered moderately challenging in the aquarium — manageable for a hobbyist with some killifish experience but less forgiving than robust community species. Aqualog recommends a minimum tank length of 15.5–23.5 in, and a well-planted species or near-species setup with subdued lighting, a dark substrate, and the addition of dried leaf litter or peat filtration to gently acidify and tannin-stain the water is the recommended approach.
The fish is peaceful toward similarly sized companions and can be kept in pairs or small groups of one male to multiple females to reduce male-on-male competition. Temperature should be held between 72–77 °F; the species does not tolerate high temperatures well, and water above 81 °F should be avoided. Regular partial water changes and stable chemistry are more important than any particular water recipe. The species is not suited to the general community tank, both because of its specific water requirements and because its small size and retiring nature make it vulnerable to boisterous tankmates.
Conservation
The IUCN Red List assessed Scriptaphyosemion guignardi as Least Concern in 2020, the evaluation conducted by Diouf, Awaïss, and Lalèyè. The species occupies multiple river systems across a comparatively wide range for a West African killifish, and no dramatic population declines have been documented, supporting the LC assessment.
Nonetheless, the lowland wetland habitats on which it depends — slow forest streams, seasonal swamps, and marshy floodplain pools — are among the most threatened freshwater environments in West Africa. Deforestation for agriculture, wetland drainage, and the expansion of rice cultivation have degraded or destroyed significant areas of suitable habitat across the Guinean lowlands and the Sahel fringe. The species' preference for soft, quiet, well-vegetated water makes it poorly suited to degraded, turbid, or disturbed streams. Hobbyist captive populations exist and are maintained through specialist killifish societies, providing a degree of insurance, but ongoing monitoring of wild populations in the Konkouré, Corubal, and Gambia River basins would be warranted as land-use pressures intensify.