Cactoblastis bucyrus is a species of snout moth

Pyralidae

The Pyralidae or snout moths are a family of Lepidoptera in the ditrysian superfamily Pyraloidea. In many classifications, the grass moths are included in the Pyralidae as a subfamily, making the combined group one of the largest families in the Lepidoptera...

 in the genus Cactoblastis

Cactoblastis

Cactoblastis is a genus of snout moths. It was described by Ragonot, in 1901, and is known from Argentina, Peru, and Brazil.-Species:* Cactoblastis bucyrus Dyar, 1922* Cactoblastis cactorum * Cactoblastis doddi Heinrich, 1939...

. It was described by Dyar in 1922, and is known from Argentina

Argentina

Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

 (Tucumán, Tapia, Mendoza, Catamarca, Andalgalá).

The head, thorax and forewings of the males are darker than any other Cactoblastis

Cactoblastis

Cactoblastis is a genus of snout moths. It was described by Ragonot, in 1901, and is known from Argentina, Peru, and Brazil.-Species:* Cactoblastis bucyrus Dyar, 1922* Cactoblastis cactorum * Cactoblastis doddi Heinrich, 1939...

species. The forewings have a few white scales. The hindwings are brownish fuscous in both sexes.

The larvae feed on Trichocereus, Echinopsis

Echinopsis

Echinopsis is a large genus of cacti native to South America, sometimes known as hedgehog cacti, sea-urchin cactus or Easter lily cactus. One small species, E. chamaecereus, is known as the peanut cactus. The 128 species range from large and treelike types to small globose cacti...

and Denmoza

Denmoza

Denmoza is a genus of cactus found in Argentina, comprising only 2 species. The name of the genus is an anagram of the western province of Mendoza. These species grow slowly and stay globulous during a long period before becoming shortly column-shaped, 0.5 to 1.5 cm high...

species.