Taxonomy & naming
Microglanis leptostriatus was described by Mori & Shibatta in 2006. It belongs to the family Pseudopimelodidae, the bumblebee and dwarf catfishes, a group that was historically lumped into Pimelodidae before being recognised as its own family; older literature and some outdated aquarium references may still place species like this one under names such as Pseudopimelodus, but the Catalog of Fishes treats Microglanis leptostriatus as the valid combination and it belongs firmly in Microglanis.
The genus Microglanis is a Neotropical assemblage of small, stocky catfishes, most no larger than a few centimetres, widely known in the trade simply as "bumblebee catfish" for their contrasting banded patterns. The species epithet leptostriatus derives from Greek/Latin roots meaning "finely striped", referring to the slender striping and blotching that distinguishes it from congeners.
Morphology
This is a genuinely small catfish: the maximum recorded size is about 1.5 in standard length, among the smallest of the bumblebee catfishes. The body is stocky and compressed, with a broad, flattened head typical of the family, barbels around the mouth, and the smooth, scaleless skin shared by pseudopimelodids and their pimelodid relatives.
The pattern is the species' calling card: a pale, contrasting band crosses a dark head, and the body carries an irregular series of pale and dark blotches rather than the clean stripes of some other bumblebee catfish. As in other Microglanis, the dorsal and pectoral fins carry stiff spines that can be locked erect — small as the fish is, those spines can still snag in a net, so it is worth scooping this species with a container rather than a net mesh.
Habitat
Microglanis leptostriatus is endemic to the middle and upper São Francisco River basin in Brazil, one of the country's major interior drainages, and it is not known from anywhere else. Within that system it occupies typical small-bodied catfish habitat along the margins and substrate of flowing water.
FishBase notes soft, slightly acidic water is preferred for breeding, at a warm 72–82 °F, consistent with the general character of South American lowland and interior river systems. As with any range-restricted river endemic, water quality and habitat integrity in the São Francisco basin matter directly to this species' status.
Feeding
Microglanis leptostriatus is a nocturnal, benthic micro-predator. In the wild it forages along the bottom after dark for small invertebrates, taking prey suited to its own diminutive size rather than the larger fare some bigger catfish relatives can manage.
In the aquarium it accepts standard ornamental fare — sinking pellets and frozen foods of an appropriately small size — but because it is most active at night, it does best when fed after the lights go out, so it is not out-competed by more visible daytime tankmates for its share of food.
Mating
Detailed accounts of courtship and spawning behaviour for Microglanis leptostriatus are sparse in the available literature. What is documented is that breeding has rarely been achieved in aquaria, and spawn — when it has occurred — has been deposited on plants rather than in a nest or cavity.
Given how little is recorded, aquarists should treat any account of pairing behaviour or sexing cues for this species as provisional rather than established fact.
Breeding
This species is not reliably bred in the home aquarium. FishBase notes that spawning has rarely been achieved in captivity, with eggs deposited on plants and no parental care described — a pattern distinct from the guarding behaviour seen in armoured callichthyid catfishes or the internal fertilisation of driftwood cats.
Most specimens in the trade are wild-collected from the São Francisco basin rather than captive-bred. Aquarists should not expect to reproduce this species reliably, and any claims of established captive breeding lines should be treated with caution absent documented sources.
In the aquarium
At barely 1.5 in, Microglanis leptostriatus is one of the more genuinely nano-sized catfish available in the hobby, suited to smaller aquaria than most catfish relatives — but its care still needs to respect its biology rather than its size alone. Aim for soft, slightly acidic to neutral water in the 72–82 °F range, with fine substrate and hiding places (roots, leaf litter, small caves) since it is nocturnal and shelters by day.
Because it is scaleless, like other pseudopimelodid and pimelodid catfish it is more sensitive than scaled fish to copper-based medications and some other treatments — dose conservatively. Its dorsal and pectoral spines can lock and catch in net mesh despite the fish's small size, so moving it in a container is gentler than netting. Keep it with peaceful, similarly small tankmates; anything large enough to see it as food should be avoided.
Conservation
The IUCN Red List assesses Microglanis leptostriatus as Least Concern (2022 assessment). As a narrow endemic restricted to the middle and upper São Francisco basin, its favourable status reflects current data rather than a wide-ranging distribution — a Least Concern listing for a single-basin endemic still depends on that basin's water quality holding up.
The São Francisco is one of Brazil's most heavily used rivers for agriculture, hydropower and water diversion, so ongoing habitat pressure in the basin is the relevant long-term watch point for a species with nowhere else to go.