The Argentine stem weevil is native to South America where it is present in Brazil, Uruguay, Argentina, Bolivia and Chile. In these countries it is not considered to be economically important. It has spread to Australia and New Zealand, in both of which countries it is regarded as a pest species. In New Zealand, it is considered to be the most important insect pest in the country, causing a total loss estimated in 1991 to be NZ$78–251 million per year.
