Taxonomy & naming
Corydoras sanchesi was described by Han Nijssen and Isaäc Isbrücker in 1967, in the Zoologische Mededelingen, from a holotype collected at Gojo Creek above Posoegroenoe in central Suriname — a tributary system on the Guiana Shield. The species is recorded in the annotated checklist of the freshwater fishes of Suriname, confirming its Surinamese type locality, and its 'Gojo cory' common name comes directly from that creek. (Some hobby lists loosely associate the species with Peru, but the authoritative type locality and primary distribution are Surinamese; we follow the original description and Catalog of Fishes.)
It belongs to the family Callichthyidae, the South American armoured catfishes, and sat for decades in the oversized genus Corydoras Lacépède, 1803. When Dias, Tencatt and colleagues split that genus in their 2024 revision, this species fell in lineage 9 and took the resurrected genus name Hoplisoma — Hoplisoma sanchesi — a combination FishBase has adopted. The aquarium world still writes 'Corydoras sanchesi', so we keep that as the heading while noting the current name. The specific epithet is a patronym, honouring a Sanchez.
Morphology
This is a small cory, reaching about 1.5 in in standard length, with the compact, deep-bodied, flat-bellied build typical of the genus. Like all corys it is armoured rather than scaled: two longitudinal rows of overlapping bony plates run down each flank, the head is a hard bony helmet, and three pairs of barbels fringe the small, downturned mouth. The snout is of moderate length, neither markedly elongate nor especially blunt.
The colour pattern is the species' calling card among the small spotted-and-blotched Guiana corys: a pale body overlaid with dark markings — typically a dark band through the eye, a darker patch or saddle on the body, and scattered spotting — set off against a lighter ground. As in all corys the dorsal, pectoral and adipose fins each carry a stiff spine. Its placement in Hoplisoma (lineage 9) reflects its phylogenetic relationships rather than any single outward feature; in the water it reads as a typical small, tidy, modestly patterned cory.
Habitat
Corydoras sanchesi is a fish of the Guiana Shield, native to central Suriname, where its type locality lies in the Gojo Creek system above Posoegroenoe, in the Saramacca–Coppename drainage region. These are small forest streams and creeks of clear to blackwater character, flowing over sand with leaf litter and submerged wood beneath the rainforest canopy.
The water is warm, soft and acidic — the soft, tannin-stained, low-mineral water typical of shield rainforest creeks. FishBase gives a temperature range of roughly 72–79 °F, a pH from about 6.0 to 8.0 and soft to moderately hard water (around 2–25 dH), though wild fish in these forest creeks experience the soft, acidic end of that range. Like other corys it keeps to the shallow, slow-flowing margins, foraging over the bottom rather than in open current.
Feeding
No dedicated dietary study has been published for Corydoras sanchesi, but it feeds as the rest of its family does: as a benthic omnivore and detritivore. It works over sand and leaf litter, using barbels and snout to taste and sift the substrate for small invertebrates, insect larvae, micro-crustaceans, worms and the organic detritus that gathers among fallen leaves and between sand grains. It is an opportunist, taking whatever small animal and plant matter the forest-stream bed offers. In the aquarium it readily accepts sinking prepared foods, frozen bloodworm and brine shrimp, and anything edible that reaches the bottom.
Mating
The spawning behaviour of Corydoras sanchesi has not been documented in detail, but corys are remarkably uniform in this respect and it follows the genus pattern. They are egg-laying shoalers without pair bonds. A receptive female cleans a spawning surface and the group becomes active; a male takes up the classic 'T-position', placing his body at right angles to the female's head, and she appears to take his milt while clasping a small batch of eggs in a basket formed by her pelvic fins. She then carries those eggs to the cleaned site and presses them into place, the sequence repeating a few eggs at a time until the clutch is laid across the chosen surfaces.
Breeding
Corydoras sanchesi is occasionally kept and spawned by cory enthusiasts; aquarist accounts of similar Guiana corys report the typical genus pattern, with spawning following the standard 'T' embrace and eggs laid in small adhesive batches on firm surfaces. Spawning is generally triggered by a cool, large water change that imitates the onset of the rains, dropping the temperature several degrees. Corys give no parental care and will eat their own eggs, so the eggs or parents must be separated. The adhesive eggs of comparable small corys hatch in a few days, after which the fry take microworm, baby brine shrimp and powdered foods and grow steadily. Detailed, species-specific spawning data for sanchesi remains limited, so these expectations are drawn from the genus and its close relatives.
In the aquarium
Corydoras sanchesi is an uncommon but rewarding small cory for the soft-water community aquarium. It is a shoaling fish and should be kept in a group of six or more; corys kept alone or in pairs are visibly stressed and far less active. A group is comfortable in a tank of around 23.5 in with ample open bottom area — footprint matters more than height. Provide soft sand or very smooth fine gravel, never sharp or coarse substrate, because corys feed by sifting and abrasive grit erodes their barbels, leading to infection and the blunted, stubby faces that mark poor husbandry.
As a Guiana Shield blackwater fish it is happiest in soft, slightly acidic, warm water (about 72–79 °F), clean, gently filtered and well-oxygenated, with leaf litter and wood to mimic its home creeks and the regular water changes any catfish appreciates; it tolerates a broad pH and hardness range but shows best in soft, acidic conditions. It is thoroughly peaceful and an ideal companion for small tetras, pencilfish, dwarf cichlids and other calm community fish, never anything large enough to bully it. The usual cory cautions apply: the stiff fin spines can tangle in a net, so a cup is safer, and a badly stressed cory can release a skin toxin that, in the small volume of a bag or bucket, can kill the whole group, so transport them carefully.
Conservation
Corydoras sanchesi is assessed by the IUCN as Least Concern, in an assessment dated 2020. It occurs across forest-creek systems of central Suriname on the relatively intact Guiana Shield, and there is no evidence of any specific threat to its populations; collection for the aquarium trade is modest. Suriname retains extensive rainforest cover, which has so far spared many of its shield-stream fishes the heavy habitat degradation seen elsewhere in the Amazon. That said, the broad regional pressures — gold mining (with its mercury and sedimentation), logging and localised pollution of forest creeks — do bear on the soft, clear waters this species needs, so its security depends on the continued health of those headwater systems.