HomeFish encyclopediaRay-finned fishesLightfishes and DragonfishesBristlemouthsHidden bristlemouth Hidden bristlemouth (Cyclothone obscura) Scientific name: Cyclothone obscura Brauer, 1902 The Hidden bristlemouth (Cyclothone obscura) is a marine fish of the family Gonostomatidae. Native range: Atlantic, Indian and Pacific, circumtropical. South China Sea. BiologyBathy- to abyssopelagic. No apparent vertical migration has been observed.Source: FishBase, licensed CC BY-NC 4.0. Species factsScientific nameCyclothone obscuraFamilyGonostomatidae (Bristlemouths)OrderStomiiformes (Lightfishes and Dragonfishes)ClassActinopterygii (Ray-finned fishes)Maximum length6.6Depth range900–3500 m (2953–11483 ft)EnvironmentMarine; bathypelagic; depth range 900 - 3500 m, usually 2000 - 2600 mClimateDeep-waterDistributionAtlantic, Indian and Pacific: circumtropical. South China Sea.Conservation status (IUCN)Not EvaluatedThreat to humansHarmlessUsesFisheries: of no interestResilienceMedium, minimum population doubling time 1.4 - 4.4 years (Fec presumed to be SourcesTaxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.Last updated 27 September 2026