Taxonomy & naming
Apricaphanius saourensis was described in 2006 by M. Carmen Blanco, Tomas Hrbek and Ignacio Doadrio as Aphanius saourensis, from the Saoura drainage of the western Algerian Sahara. The specific epithet is a toponym referring to the Oued Saoura, the wadi system that gives the species its only known range. It was later transferred to Apricaphanius, a genus erected to hold this species alongside the Iberian toothcarp Apricaphanius baeticus, following molecular work that showed the two — geographically separated by the width of the western Mediterranean — to be more closely related to each other than either is to other Aphanius-group lineages. Eschmeyer's Catalog of Fishes lists the valid combination as Apricaphanius saourensis (Blanco, Hrbek & Doadrio, 2006).
The Apricaphanius/Aphanius/Aphaniops/Anatolichthys complex of genera reflects a broader taxonomic reorganisation of what was once a single very broadly defined Aphanius across the Mediterranean, Middle East and Central Asia; the Saoura toothcarp's placement with the Iberian species is one of the more striking biogeographic results of that work, implying an old, disjunct relict distribution either side of the Strait of Gibraltar and the Sahara.
Morphology
Apricaphanius saourensis is a small killifish, consistent in general body plan with its relative A. baeticus: a stout, laterally compressed body, blunt head and upturned mouth suited to feeding near the surface of shallow desert pools. Detailed published morphometrics specific to A. saourensis were not confidently available from the sources consulted here, but sexual dimorphism of the pattern typical for the genus — barred, more colourful males and plainer females — is expected.
Habitat
The species is known from the Oued Saoura and associated oasis pools in the Grand Erg Occidental region of western Algeria, an endorheic desert drainage sustained largely by fossil groundwater discharging through springs and irrigation channels rather than by significant rainfall. This is among the most extreme environments occupied by any Aphaniidae: high evaporation, strongly seasonal and often very high water temperatures, and a hydrology entirely dependent on aquifer discharge that has been heavily exploited for oasis agriculture across the twentieth and twenty-first centuries.
Declining spring flow and the conversion of natural wadi pools into managed irrigation channels have reduced and fragmented the habitat available to the species. Some field reports have raised concern that the historically documented sites may no longer hold water year-round, which is the basis for the species' listing at the most severe CARES priority tier.
Feeding
No dedicated dietary study of Apricaphanius saourensis has been located. As with other small Aphaniidae of similar oasis and spring habitats, an omnivorous diet of algae, detritus and small invertebrates is inferred from the genus rather than confirmed directly for this species.
Mating
Courtship and spawning behaviour specific to Apricaphanius saourensis have not been documented in the sources consulted. The genus as a whole follows the general Aphaniidae pattern of non-annual, iteroparous plant- and substrate-spawning, with males displaying to females and pairs depositing small batches of adhesive eggs over an extended period rather than in a single event.
Breeding
Published information on the captive breeding of Apricaphanius saourensis specifically is data sparse. Given the severity of its wild conservation status, any surviving captive lines held by specialist killifish keepers or conservation institutions would carry considerable value as an insurance population, but no established breeding protocol specific to this species was confirmed from the sources available here.
In the aquarium
Apricaphanius saourensis is essentially unknown in the general aquarium trade. Given the severity of concern over its wild status, any specimens that do exist in captivity should be understood as part of a conservation-breeding effort rather than an ordinary hobby fish, and anyone encountering the species should treat sourcing and record-keeping with particular care. General husbandry for hardy Saharan and Mediterranean Aphaniidae — hard, mineral-rich water, warm temperatures and tolerance of some salinity — likely applies, but specific parameters for this species are not confirmed.
Conservation
The CARES Preservation Program lists Apricaphanius saourensis at its most severe priority tier, Extinct in the Wild (CEW), reflecting serious concern among specialists that the species' native Saoura oasis habitat may no longer support a viable wild population following decades of groundwater extraction for irrigation across the Algerian Sahara. This assessment should be read as a statement of grave concern from the conservation-aquarist community rather than as a formal, universally confirmed declaration of extinction in the wild — the precise current status of any remaining wild population is not well documented in the sources available here.
What is clear is that the underlying threat — depletion of fossil groundwater feeding Saharan oasis systems — is a pattern affecting numerous other narrow-range desert fish across North Africa and the Middle East, and is generally irreversible on any short timescale. If any captive lineage of A. saourensis exists, its careful maintenance and, ultimately, potential future reintroduction would represent one of the few realistic paths back from this listing.