Taxonomy & naming
Akama and Ferraris described the species in 2011. The Catalog of Fishes lists Spinipterus acsi as valid, with the type locality at Caño Santa Rita, a right-bank tributary of the río Nanay, about 3 mi north-west of Iquitos, Maynas Province, Loreto, Peru. The family Auchenipteridae holds the driftwood catfishes.
Morphology
FishBase gives a maximum length of 1.5 in SL, which makes it one of the smallest members of its family. The genus name refers to the spine of the fin.
Habitat
FishBase lists Peru, and says the species is known only from the type locality. It describes it as a freshwater fish of the tropics living in the water column near the bottom. No temperature or pH range is given.
Feeding
No diet is recorded for this species.
Mating
Auchenipterids fertilise internally, but no description of mating is recorded for this species.
Breeding
Breeding is not recorded for this species.
In the aquarium
The fish is not in the trade and no husbandry is recorded.
Conservation
IUCN lists the species as Data Deficient, assessed in 2020. Its known range is a single stream, so any loss of forest or water quality there would bear on the whole species.