[1][2][3][4] The adult of Naupactus leucoloma is dark grey in colour with two lighter-coloured bands running longitudinally down its thorax and head.

Wings of N. leucoloma vary greatly in size between individual specimens, but the forewings are fused, thus making the adults unable to fly.

[7][5] Males of N. leucoloma are rare and only occur in the native range of South America, but also may be extinct.

[9] Outside the native range, N. leucoloma has also been introduced through anthropological means to the United States, South Africa, Chile, Peru, Australia and New Zealand where it is well established[10][9][11] Naupactus leucoloma was first found in New Zealand in 1944 and is now well established through most of the North Island.

[12] It has since been recorded in several parts of the South Island as well, including Nelson, Blenheim, Christchurch and Ashburton.

[12] Naupactus leucoloma is a pest in its non-native range and feeds on 385 different plant species including beans, clover, potatoes and many more.

Some of these species include alfalfa, beans, brassicas, carrots, clover, onions and potatoes.

[17] House Sparrows (Passer domesticus) have been observed eating Naupactus leucoloma in New Zealand.