Taxonomy & naming
The chop stick cory was described in 1970 by Han Nijssen, the Dutch ichthyologist whose work underpins much of cory taxonomy, and named coppenamensis for the Coppename River of Suriname, its type locality. For over half a century it sat in the great genus Corydoras Lacépède, 1803 (family Callichthyidae), and the hobby still uses that name.
The 2024 revision of the subfamily Corydoradinae by Dias, Tencatt and colleagues divided the oversized Corydoras among several genera, and under that scheme this species moves to the resurrected genus Hoplisoma Agassiz, 1846 — the lineage that holds a great many of the spotted and saddled corys of the trade. Eschmeyer's Catalog of Fishes and FishBase now list the combination Hoplisoma coppenamense, which we note here while retaining the familiar Corydoras heading. The species sits within a tight knot of small, very similar Guiana-Shield corys — alongside C. bondi and C. sipaliwini — distinguished by subtle differences in pattern and proportion: its markings are reportedly crisper and less blurred than those of C. bondi, and its body slightly more elongate with a rounder head.
This fish was long listed as Corydoras coppenamensis; Eschmeyer's Catalog of Fishes places the species in Hoplisoma, and the current combination Hoplisoma coppenamense is followed here.
Morphology
This is one of the smaller corys, reaching only about 1.6 in standard length, with the compact, plated build of the subfamily: two rows of overlapping bony scutes down each flank, a hard blunt head, and three pairs of barbels around the downturned mouth. Its colour is a clean spotted-to-marbled pattern, and that comparative crispness — sharper and less smudged than the closely allied C. bondi — is one of the cues used to separate it from its Guiana-Shield neighbours, along with a marginally more elongate body and a rounder head profile.
As in all corydoradines, the dorsal and pectoral fins carry stiff, mildly venomous spines that double as a defence and a hazard around nets. It is otherwise an unshowy little fish whose interest lies mostly in its place within a difficult species complex.
Habitat
Hoplisoma coppenamense is endemic to the Coppename River basin in Suriname, on the Guiana Shield of north-eastern South America. These are warm Guianan rainforest streams and river margins over sand and leaf litter, ranging from clear to lightly tannin-stained water beneath forest canopy.
Reported parameters reflect that setting — temperatures around 72–79 °F, a pH spanning acidic to slightly alkaline (about 6.0–8.0), and soft to moderately hard water. It is a bottom-dweller of quieter reaches and shallow margins, and, like other corys, a facultative air-breather able to gulp atmospheric oxygen through its hindgut in the warm, oxygen-poor pools that form in such streams during the dry season.
Feeding
Like its relatives, the chop stick cory is a benthic foraging omnivore. It works the sandy, litter-strewn bottom of its home streams, sifting with its barbels to find small invertebrates, insect larvae, worms and organic detritus. In the aquarium — where it appears only occasionally — it takes the standard small foods: sinking dried pellets and tablets, frozen and live bloodworm, Tubifex and brine shrimp. As with all corys it does best on a varied diet and should not be left to scavenge leftovers alone.
Mating
Spawning has not been documented in detail for H. coppenamense, but it is expected to follow the corydoradine norm: an egg-laying shoaler with no pair bond, in which a ready female cleans a site, the group becomes active, and a male takes the 'T-position' at right angles to her head. The female carries a few eggs at a time in a basket formed by her pelvic fins and presses them onto the cleaned surface, repeating in small batches until a scatter of adhesive eggs has been laid. This account reflects the group rather than direct observation of this species.
Breeding
Captive breeding of the chop stick cory is essentially unrecorded; it is a rare import, not a farmed species. By analogy with related Guianan corys, spawning would be encouraged by soft water and a cooler, rain-mimicking water change, producing small clutches of adhesive eggs laid on plants, wood and glass with no parental care — the adults will eat the spawn, so a breeder separates eggs or parents. Eggs of comparable small corys hatch within a few days and the fry take microworm and baby brine shrimp once free-swimming. Specific clutch sizes and timings for this species are not on record, so these remain expectations drawn from its relatives.
In the aquarium
Hoplisoma coppenamense is a fish for the cory specialist and biotope keeper rather than the general aquarist — seldom imported and most likely wild-caught when available. Its care is standard cory practice: keep it in a shoal of six or more, over soft sand that protects its barbels, in clean, gently moving, well-oxygenated water.
Reflecting its Guianan origin it does well in soft to moderately hard water of moderate pH in the 72–79 °F range, and appreciates some leaf litter or botanicals for cover and a touch of tannin. It is wholly peaceful and suits a quiet community of small, calm fishes; given how alike it and its relatives are, a careful keeper avoids mixing it with C. bondi or C. sipaliwini unless intentionally maintaining a single clean species. Lift it with a cup rather than a net to avoid snagging the fin spines, and transport with care, as a stressed cory can release skin toxins in the confined volume of a bag.
Conservation
Hoplisoma coppenamense is assessed by the IUCN Red List as Least Concern, evaluated in 2007. It is a single-basin endemic of the Coppename, much of which still flows through intact and partly protected forest in central Suriname, and no specific threat to it is recorded. Even so, a one-river range carries inherent risk: the broad pressures on Guiana-Shield rivers — gold-mining and its mercury pollution, deforestation and watercourse disturbance — could degrade its habitat, and a narrow endemic has little margin if its single drainage is disrupted.