HomeFish encyclopediaRay-finned fishesFlatfishesSolesRobert?s Sole Robert?s Sole (Leptachirus robertsi) Scientific name: Leptachirus robertsi Randall, 2007 The Robert?s Sole (Leptachirus robertsi) is a freshwater fish of the family Soleidae. Native range: Oceania, Papua New Guinea. BiologyDorsal soft rays (total): 66-74; Anal soft rays: 50 - 57; Vertebrae: 38 - 40. This species is distinguished by the following characters: D 66-74; A 50-57; pelvic rays 4; lateral line on ocular side of head with a ventral branch of 5-7 pored scales, remaining horizontal anterior part with 4-5 pored scales; lateral-line scales to point of branching on head 78-87, including 8-9 anterior to upper end of gill opening; vertebrae 38-40; dorsal pterygiophores anterior to fourth neural spine 8-9; body slender, depth 3.0-3.15 in SL; head length 4.0-4.25 in SL; no caudal-peduncle; eye diameter 5.7-8.1 in HL; least vertical interorbital width 11.2-26.0 in HL; scales of body of adults with 8-12 cteni (mostly 9 or 10); longest dorsal ray 1.8-2.15 in HL; caudal fin 3.8-4.3 in SL; origin of pelvic fins adjacent on ventral edge of body, the fins attached posteriorly to base of anal papilla; short pelvic fins, reaching base of first anal ray, 2.7-2.9 in HL; ocular side brown, finely mottled witSource: FishBase, licensed CC BY-NC 4.0. Species factsScientific nameLeptachirus robertsiFamilySoleidae (Soles)OrderPleuronectiformes (Flatfishes)ClassActinopterygii (Ray-finned fishes)Maximum length7.1Depth range0–1 m (0–3 ft)EnvironmentFreshwater; benthopelagic; depth range 0 - 1 mClimateTropicalDistributionOceania: Papua New Guinea.Conservation status (IUCN)Not EvaluatedThreat to humansHarmlessResilienceHigh, minimum population doubling time less than 15 months (Preliminary K or Fecundity.) SourcesTaxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.Last updated 27 September 2026