Taxonomy & naming
Aspidoras gabrieli was described in 2014 by Wolmar Wosiacki, Priscila das Graças Pereira and Roberto Reis, from an unnamed tributary on the left bank of the rio Parauapebas — itself a tributary of the rio Itacaiúnas in the lower rio Tocantins basin — in the Serra dos Carajás, Pará State, Brazil. The genus Aspidoras Ihering, 1907 is a small group of exclusively Brazilian armoured catfishes (family Callichthyidae, subfamily Corydoradinae), allied to Corydoras but distinguished by skull anatomy, including two cranial fontanels.
The broad 2024 revision of the Corydoradinae by Dias, Tencatt and colleagues (DOI 10.1093/zoolinnean/zlae053) split the swollen genus Corydoras into several genera (Brochis, Hoplisoma, Gastrodermus, Osteogaster and others) but retained Aspidoras as a distinct, intact lineage — so the species stays Aspidoras gabrieli, and Catalog of Fishes (Eschmeyer, CAS) lists it as valid. Tencatt and co-authors (2021) examined the species in their genus revision: because it is remarkably similar to, and shares the Tocantins basin with, A. albater, they re-examined its diagnosis closely but confirmed that at least two characters reliably separate the two, and A. gabrieli remains valid.
Morphology
Aspidoras gabrieli is a small catfish reaching about 1.5 in in standard length — among the larger members of this dwarf genus — with the standard corydoradine build: an armoured, deep body sheathed in two rows of overlapping bony scutes, three pairs of barbels around a small ventral mouth, and stiff dorsal and pectoral spines. As in all Aspidoras, the skull carries two fontanels.
It was diagnosed chiefly on two features. First, the rays and interradial membranes of the dorsal and pectoral fins are densely pigmented from base to tip in young individuals, the pigment gradually retreating from the fin tips with age. Second, the dorsolateral body plates of the predorsal region are set noticeably farther apart from their counterparts than in most congeners, leaving a wider gap along the back. Internally it has an extremely well-developed inner laminar expansion on the first infraorbital bone and a relatively broad frontal bone, and it shows a smoothly (rather than sharply) furcate caudal fin — characters that, in combination, separate it from the very similar A. albater.
Habitat
Aspidoras gabrieli is known from small streams in the Serra dos Carajás, an upland of eastern Amazonian Pará, where its records come from tributaries of the rio Parauapebas in the lower rio Tocantins basin. These are clear, shallow forest streams over sand and litter, the characteristic habitat of dwarf corydoradines.
Like other members of the genus and the broader Corydoradinae, it is presumed capable of facultative air-breathing, gulping atmospheric oxygen to cope with warm, sometimes oxygen-poor water. Specific temperature, pH and hardness measurements for the species have not been published, so the figures used by aquarists are inferred from the soft, warm, slightly acidic waters of the Carajás streams rather than recorded directly for this fish.
Feeding
No targeted dietary study exists for Aspidoras gabrieli, but on the model of its genus and the Corydoradinae it is a benthic micro-omnivore. It sifts soft sediment and leaf litter with its barbels for small invertebrates, insect larvae, microcrustaceans and organic detritus, expelling cleaned sand through the gill openings. This account is inferred from its relatives rather than observed for the species itself.
Mating
Courtship in Aspidoras gabrieli has not been described, but the species is an egg-layer that should follow the corydoradine pattern. Aspidoras and Corydoras are shoaling spawners without pair bonds: a receptive female cleans a surface, the group becomes active, a male pairs with her briefly to fertilise the eggs, and she then clasps a small number of adhesive eggs at a time in her pelvic-fin basket and presses them onto the chosen site, repeating until the clutch is complete.
Breeding
No breeding data have been published for Aspidoras gabrieli — clutch size, egg development, fry growth and spawning triggers are all undocumented for this species. The fact that it was described from a conspicuously large type series implies it is numerous in the wild and reproduces successfully there. By analogy with related Aspidoras, it would be expected to lay modest batches of adhesive eggs that receive no parental care, hatching within a few days into free-swimming fry that take infusoria and then micro-foods; the species has, however, no established captive-breeding record.
In the aquarium
Aspidoras gabrieli is little known to the hobby and only sporadically, if ever, available, so there is scant tested husbandry for it. Should it be kept, it would need the standard small-Aspidoras provisions: a shoal of six or more, since these are social fish that languish when kept alone; a soft sand substrate to protect the barbels from abrasion and infection; gentle, well-oxygenated flow with clean water and regular changes; warm but not hot water in the low-to-mid 20s Celsius; and small, peaceable tankmates. Leaf litter and shaded cover suit the genus, and care with nets is wise given the fin spines. These are recommendations drawn from its relatives rather than guidance proven on this particular catfish.
Conservation
Aspidoras gabrieli is assessed by the IUCN Red List as Least Concern (2018), a conclusion echoed by the 2021 generic revision. Although its known distribution in the Serra dos Carajás is geographically restricted, the species was described from a large type series indicating that it is abundant in its habitat, and no specific threat to it has been identified. The notable caveat is location: the Serra dos Carajás holds some of the world's largest iron-ore mining operations, so the small Amazonian streams this endemic depends on lie within an intensively industrialised landscape where sedimentation, water diversion and habitat alteration are real long-term concerns, warranting continued attention even for a currently secure species.