Taxonomy & naming
Platystomatichthys sturio was described by Rudolf Kner in 1858 in another genus, as the parentheses show, and is valid in the Catalog of Fishes. It belongs to the Pimelodidae, the long-whiskered catfishes. The genus name means flat-mouthed fish, and the epithet sturio, Latin for sturgeon, names the long snout. Wet Spot has sold it under its scientific name.
Morphology
FishBase gives a maximum length of 15.5 in TL for males or unsexed fish. The body is long and slim, the snout is flattened and drawn out, and the barbels are long, in the manner of the family.
Habitat
FishBase records the species from the Amazon basin as freshwater, demersal and tropical, with a temperature of 70–77 °F, a pH of 6.0 to 7.5 and a hardness up to 18 dH. The type locality is the Rio Branco in Brazil.
Feeding
No detailed diet is recorded for this species. A bottom-living, long-snouted pimelodid of this size can be expected to eat small fish and invertebrates, and keepers should plan for that.
Mating
Courtship has not been described.
Breeding
No spawning or egg information is recorded, and aquarium breeding is not documented.
In the aquarium
At up to 15.5 in TL it needs a long tank with open floor and cover, and it will eat fish small enough to swallow. FishBase gives 70–77 °F and a pH of 6.0 to 7.5, which is the cooler end of tropical water. Offer meaty sinking foods after dark.
Conservation
IUCN assessed the species as Least Concern on 28 December 2020. No specific threat is recorded.