Taxonomy & naming
Devario spinosus was described by Francis Day in 1870, the parenthetical authority in its current combination marking the move out of Day's original genus placement. The Catalog of Fishes (Eschmeyer, CAS) records Devario spinosus (Day, 1870) as the valid name. FishBase assigns it the identifier FB 24396 and confirms both the authority and the Myanmar distribution.
The genus Devario encompasses the giant danios and their allies — larger, more robust danionins than the slender members of Danio sensu stricto. The genus was substantially redefined in the late twentieth and early twenty-first centuries as molecular and morphological work separated Devario from the smaller Danio and carved out additional genera such as Microdevario and Inlecypris. Devario spinosus has not been involved in any major revisionary splits or synonymies noted in accessible literature, and it sits in Devario on the basis of general morphological affinity.
Morphology
Devario spinosus reaches a maximum recorded total length of 4 in, placing it among the larger members of the genus alongside species such as D. devario and D. aequipinnatus. Like other Devario, it is expected to have a slender, laterally compressed body, a terminal to slightly upturned mouth suited to mid-water and surface feeding, and a streamlined form consistent with life in flowing water.
The species takes its name from its most diagnostically useful feature: a sharp spine-like process on the anterior superior margin of the orbit (eye socket). The ETYFish Project records this directly from Day's original 1870 description, where spinosus — Latin for "bearing a spine" — refers to this characteristic projecting ridge above the front of the eye. Beyond this orbital detail and the general Devario body plan, detailed morphometric data for D. spinosus are sparse in the accessible literature.
Habitat
Devario spinosus is recorded from Myanmar, where it is apparently endemic. FishBase classifies it as a freshwater, benthopelagic species with a tropical thermal profile. As a member of Devario — a genus broadly associated with flowing streams and rivers across South and Southeast Asia — D. spinosus is expected to inhabit well-oxygenated, moving freshwater systems rather than still or stagnant waters.
No species-specific habitat data (substrate, riparian vegetation, current speed, water chemistry) have been captured in the accessible literature for this species. Habitat inferences for D. spinosus must therefore draw on the broader Devario ecology: clear to moderately turbid rivers and hill streams, often with gravel or rocky substrates, where the genus typically occurs in schools in the mid-water column and near the surface. The precise river systems within Myanmar to which this species belongs have not been documented in the sources consulted.
Feeding
FishBase assigns Devario spinosus a trophic level of 3.0, consistent with a generalised omnivore or invertebrate predator occupying a mid-position in the food web. This trophic value aligns with the broader Devario feeding strategy: these are opportunistic, active fish that take insects and their aquatic larvae, small crustaceans, worms, and organic detritus, with some plant material and algae supplementing the diet.
In the absence of species-specific gut-content studies for D. spinosus, it is reasonable to infer that it feeds in the manner typical of the genus — actively patrolling the mid-water and surface in schools, exploiting drift invertebrates and surface-fallen insects as well as bottom-dwelling invertebrates, given its benthopelagic habitat classification. No feeding observations or dietary analyses specific to this species are documented in the sources consulted.
Mating
Devario spinosus is an egg-scattering, non-guarding spawner in the manner universal among Devario and the broader danionin tribe. There is no parental care, no nest construction, and no pair bond beyond the act of spawning. Gravid females are pursued by males through the water column and among vegetation; eggs and milt are released together in brief contact, after which the adults take no further interest in the spawn.
FishBase records breeding data as sparse for this species, and maturity parameters are not documented. The general Devario reproductive pattern — triggered by seasonal warmth, rising water levels and food availability, with spawning occurring over fine-leaved plants, moss, gravel or similar substrates — is the most reliable framework available for D. spinosus in the absence of species-specific records.
Breeding
No captive breeding records for Devario spinosus are available in the literature or hobbyist sources consulted. Given the species' apparent rarity in the aquarium trade and the very limited documentation of its biology, practical breeding information must be extrapolated from well-studied congeners such as D. aequipinnatus and D. devario.
By analogy with those species, D. spinosus would be expected to scatter adhesive or weakly adhesive eggs over fine-leaved plants, Java moss or a gravel substrate; parents give no care and should be removed after spawning to prevent egg predation. Eggs would hatch within two to three days at tropical temperatures, with free-swimming larvae appearing a few days later. Conditioning on live and frozen invertebrates is likely to stimulate spawning. These points remain inferential, and direct breeding records would be required to confirm the reproductive biology of this species.
In the aquarium
Devario spinosus does not appear in mainstream aquarium trade catalogues or regularly in hobbyist literature, and there are no care profiles for this species in the sources consulted. Its size — up to 4 in TL — means that if kept, it would require a spacious aquarium with generous swimming room; Devario of this size are active, fast-moving schooling fish that do poorly in cramped conditions.
By general Devario husbandry principles, D. spinosus would be expected to prefer well-oxygenated, moving water with moderate current, a long tank with open mid-water space and some planted cover, and broadly neutral, moderately soft to medium-hard water reflecting Myanmar riverine conditions. A school of at least six individuals would be appropriate for normal behaviour. It would almost certainly accept standard aquarium foods — dry flake and pellet, supplemented with live and frozen invertebrates. These recommendations are provisional in the absence of direct keeping records.
Conservation
Devario spinosus has not been assessed by the IUCN Red List and its conservation status is therefore Not Evaluated (NE). The species appears to be endemic to Myanmar, a country whose freshwater ichthyofauna is subject to growing pressure from deforestation, agricultural runoff, artisanal fisheries, dam construction and general watershed degradation.
The lack of any IUCN assessment reflects the species' obscurity in the literature rather than confirmed security: many Myanmar endemic fishes are poorly documented and have received no formal threat evaluation. Until population surveys establish the range, abundance and habitat condition of D. spinosus, its vulnerability to the broad pressures affecting Myanmar's river systems cannot be gauged. The narrow endemic distribution implied by the available records is itself a flag for potential vulnerability if habitat quality declines.