Adults are demersal and search for prey along the ocean floor, primarily fish, cephalopods, and crustaceans.

Its low reproductive rate and the time it takes for juveniles to mature make it vulnerable to expanding deep-sea fisheries, but it is listed as Least Concern by the International Union for Conservation of Nature (IUCN) due to its extensive range.

The first scientific description of the alfonsino was authored in 1829 by Georges Cuvier in the third volume of his 22-volume ichthyology collection, Histoire Naturelle des Poissons,[3] who gave it the name Beryx dodecadactylus.

[4] The alfonsino has large eyes and a deep, compressed body, 1.9–2.5 times its standard length at the greatest depth.

[1] Alfonsinos are batch spawners, that is they release eggs multiple times over an extended spawning season rather in a short period.

[7] Eggs hatch after around 27 hours and larvae are initially 1.5–3.0 mm (0.059–0.118 in) SL in size, identifiable by pigment near the brain.

Flexion, when the larva bends upwards prior to development of the caudal fin, occurs at 3.7–6.0 mm (0.15–0.24 in) SL.

They are distinguished by elongated pelvic rays and anterior dorsal spines as well as pigment near the gas bladder, though they are very similar to the larvae of the splendid alfonsino.

[7] After 4 years, they reach sexual maturity, at which point they will be about 30 cm (12 in) in size, with females being slightly larger on average than males.

It is listed as Least Concern by the International Union for Conservation of Nature (IUCN) because its extensive distribution protects it from danger of extinction and in parts of its range it is not a targeted species.

It could also be threatened by habitat loss due to deep-water trawling causing damage to deep-sea corals.