Taxonomy & naming
Curculionichthys monolechis was described in 2024 by Moraes, Gamarra and Reis, a recent addition to the genus Curculionichthys within the subfamily Hypoptopomatinae — the dwarf suckermouth catfishes allied to Otocinclus. The species is recognised as valid in FishBase.
Its discovery is notable on biogeographic grounds: Curculionichthys is otherwise an essentially Brazilian-Shield genus, so the placement of C. monolechis in the Guianan drainages of Suriname and French Guiana marks an unusual extension of the genus's known range.
Morphology
Curculionichthys monolechis is a tiny fish, reaching only about 1 in standard length — placing it among the smallest of all loricariids. It has the compact, armoured body typical of the Hypoptopomatinae, with bony lateral plates and the ventral suckermouth shared across the subfamily.
The formal diagnostic characters separating it from congeners are set out in the 2024 description; beyond the small body size, additional morphological detail is not summarised in the sources reviewed here. No data on sexual dimorphism has been published in the references consulted.
Habitat
The species occurs in the Saramacca and Marowijne (Maroni) river basins of Suriname and French Guiana. It is a freshwater, demersal, tropical fish.
Fine-scale habitat data — substrate, water chemistry, current, and microhabitat — has not been published in the sources available here. Members of the Hypoptopomatinae generally cling to plants, leaf litter, and submerged surfaces in clear-water streams, but this has not been documented specifically for C. monolechis.
Feeding
No diet study has been published for Curculionichthys monolechis in the sources consulted. Dwarf Hypoptopomatinae are typically aufwuchs grazers, rasping algae and biofilm from hard surfaces and plant leaves, and this feeding mode can reasonably be expected for the species — but it has not been confirmed.
Mating
No information on courtship or mating behaviour in C. monolechis has been published in the references reviewed here.
Breeding
No breeding accounts exist for Curculionichthys monolechis in the sources consulted, and there are no documented records of aquarium reproduction. As a very recently described species, its reproductive biology remains entirely unstudied in the available literature.
In the aquarium
Curculionichthys monolechis is not established in the aquarium hobby, and no husbandry accounts exist in the sources reviewed here. Given its minute size and Guianan stream origin, any care regime would have to be inferred from related dwarf Hypoptopomatinae — but no species-specific guidance can be offered without published data.
Conservation
Curculionichthys monolechis has not yet been evaluated by the IUCN Red List (status Not Evaluated). As a species described only in 2024, it has not been through a formal conservation assessment, and no information is available on population size, trend, or threats.