HomeFish encyclopediaRay-finned fishesPerch-like fishDottybacksThomasen's snakelet Thomasen's snakelet (Halidesmus thomaseni) Scientific name: Halidesmus thomaseni Nielsen, 1961 The Thomasen's snakelet (Halidesmus thomaseni) is a marine fish of the family Pseudochromidae. Native range: Indian Ocean, Pakistan and the coasts of northern India. BiologyDorsal spines (total): 1; Dorsal soft rays (total): 58-64; Anal spines: 0; Anal soft rays: 45 - 50; Vertebrae: 64 - 68. Dorsal lateral line (LL) unbranched; ventral LL consists of a single section on each side of the abdomen; LL pores opening from middle of posterior margins of LL scales. Operculum with scales. A dark spot above the pectoral fin.Source: FishBase, licensed CC BY-NC 4.0. Species factsScientific nameHalidesmus thomaseniFamilyPseudochromidae (Dottybacks)OrderPerciformes (Perch-like fish)ClassActinopterygii (Ray-finned fishes)Maximum length13.2EnvironmentMarine; demersalClimateSubtropicalDistributionIndian Ocean: Pakistan and the coasts of northern India.Conservation status (IUCN)Not EvaluatedThreat to humansHarmless SourcesTaxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.Last updated 27 September 2026