Taxonomy & naming
Boehlkea weitzmani was described by Soares, Bertaco, Ito and Zuanon in 2017 in the journal Neotropical Ichthyology (vol. 15, no. 3, article e170026). The paper placed the new species within the subfamily Stevardiinae of the family Characidae and assigned it to the genus Boehlkea, a small neotropical genus named after the American ichthyologist James Elias Böhlke (1930–1982) of the Academy of Natural Sciences of Philadelphia. The type locality lies within the rio Japurá drainage, rio Solimões basin, in Amazonas state, Brazil.
The genus Boehlkea had previously contained only its type species, the Blue Tetra, B. fredcochui. The addition of B. weitzmani extends the genus into a distinct drainage and habitat type. The specific epithet honours Stanley H. Weitzman, the eminent Smithsonian ichthyologist whose work on the systematics and biogeography of characiform fishes underpins much of the modern classification of the family. Meristic characters recorded for the species include 10 dorsal soft rays, 21 anal soft rays, and 36–38 vertebrae.
Morphology
Boehlkea weitzmani is a small, slender characid reaching a maximum recorded standard length of 1.5 in. Like other stevardiin tetras it is laterally compressed with the typical characid body plan: a single dorsal fin, a small adipose fin, and a forked caudal fin. The species has not been illustrated in widely available hobbyist literature and detailed colouration data from the original description or secondary literature are limited in English-language sources.
The combination of small size, slender form, and the upland stream habitat in the Japurá drainage distinguishes B. weitzmani ecologically from the better-known Blue Tetra (B. fredcochui) of lowland blackwater streams in the rio Negro system. At 1.5 in SL it sits at the smaller end of the genus and of Stevardiinae generally.
Habitat
The species is known from narrow upland forest streams in the rio Japurá drainage of Amazonas, Brazil. Field data recorded at collection sites describe watercourses of 4–9 ft width and 0–1 ft depth — barely more than ankle-deep riffles and pools threading the forest floor. Water conditions are characteristically oligotrophic: clear to yellowish, acidic (pH below 6.6), cool for Amazonia (75–78 °F), well-oxygenated (dissolved oxygen 3.49–7.8 mg/l), and with low conductivity (below 33.3 µS/cm). The substrate is white silica sand and pebbles with accumulations of leaf litter along the banks.
This combination — narrow, shallow, shaded, cool, acidic, low-nutrient — places B. weitzmani firmly in the upland igarapé (forest stream) biome. Such habitats are highly sensitive to deforestation and land-use change because the forest canopy directly controls water temperature, shading, and allochthonous input of leaf litter and terrestrial invertebrates.
Feeding
No detailed dietary study specific to Boehlkea weitzmani has been published in accessible literature. Based on its habitat and the feeding ecology of comparably sized Stevardiinae and other small upland stream characids, the species likely functions as a micropredator, taking aquatic insect larvae, small crustaceans, worms, and surface-fallen invertebrates. Leaf litter banks in igarapé streams support a diverse invertebrate community that small characids exploit heavily.
In captivity, members of the genus Boehlkea and similar small Stevardiinae accept fine dried foods but generally respond best to a mixed diet that includes frozen or live micro-invertebrates such as Daphnia, copepods, and small mosquito larvae. Data sparse beyond this inference from ecology and related taxa.
Mating
No specific spawning observations for Boehlkea weitzmani appear in the published literature available at the time of writing. By analogy with other small Stevardiinae and with the genus Boehlkea generally, the species is expected to be an egg-scattering open spawner that deposits adhesive eggs among fine-leaved plants or leaf litter without subsequent parental care. Males in breeding condition in related species typically display to females through fin erection and colouration, with spawning occurring near cover.
The cool, acidic, well-oxygenated conditions of its native streams suggest that replicating low temperatures and soft, acidic water may be important for inducing spawning in captivity, as is the case for many upland igarapé tetras.
Breeding
Captive breeding of Boehlkea weitzmani has not been documented in available English-language hobby literature. The species is not yet established in the ornamental trade under this name. Its close relative B. fredcochui (Blue Tetra) is bred in captivity by specialists using soft, slightly acidic water, fine-leaved plants or spawning mops, and removal of adults after spawning to prevent egg predation — a protocol that is likely applicable to B. weitzmani given the shared genus and the soft-acid conditions of its natural habitat.
Egg-scattering mode with no parental care is the expected reproductive strategy, with adhesive eggs deposited among vegetation and hatching within a few days at appropriate temperatures. Fry of similarly sized characids typically require infusoria or rotifers as first foods before graduating to nauplii.
In the aquarium
Boehlkea weitzmani is not yet widely available in the aquarium trade. Any specimens that reach hobbyists will be wild-caught given the absence of established captive populations, and should be considered delicate fish requiring conditions that closely match those of the type locality: soft, acidic water (pH below 6.5), cool temperatures (73–77 °F), low conductivity, high dissolved oxygen, and subdued lighting over a dark sand substrate with leaf-litter cover. A well-filtered, heavily planted nano tank of 10–15 US gal would suit a small group.
The species is too small and specialist for community tanks with larger or more boisterous fish. Suitable companions, if tankmates are desired, are other small igarapé tetras, small Corydoras, and similarly delicate nano fish that tolerate the same soft, cool conditions. Given its limited known distribution and undocumented status in the hobby, every effort should be made to source any specimens ethically and to maintain detailed records of captive care for the benefit of hobbyist knowledge of the species.
Conservation
Boehlkea weitzmani has not been assessed by the IUCN Red List as of 2026. Its conservation status is therefore formally Not Evaluated. The species is known only from the rio Japurá drainage in Amazonas state, Brazil — a restricted range within an upland forest stream habitat that is inherently vulnerable to deforestation and agricultural expansion along watercourse margins.
The narrow, shallow streams it inhabits are highly sensitive to canopy removal, which raises water temperatures and alters the organic-input regime that underpins the invertebrate prey community. Brazil's Amazonas state retains large intact forest cover in the core of the basin, but the Japurá corridor is subject to ongoing pressure. Given the species' recent description and limited distributional data, a formal IUCN assessment would require additional field surveys to establish population size and range. Until such an assessment is completed, precautionary management of the habitat catchment is the most meaningful conservation measure available.