Insects: Blister Beetles

Taxonomy:

Distribution:

• Widespread

Importance:

• Blister beetle larvae are considered beneficial because they feed on grasshopper eggs.


• Adults are potentially damaging foliage-feeders.

Identification:

• Adult have broad heads, narrow necks, and vary from ½ to 1 inch in length.


• The body is very soft.


• Two of the most common include the margined and striped blister beetles.


• The margined blister beetle is black, gray, or a mixture of the two colors.


• Striped blister beetles are yellowish-orange with brown stripes.


• Larvae are pale in color.

Life Cycle:

• Blister beetles over winter as late instar larvae 1 to 2 inches deep in the soil.


• Over wintered larvae pupate in the spring, and adults emerge in late spring.


• During the summer, adults feed on foliage and flowers.


• Females lay eggs in the soil.


• Eggs hatch in 1 1/2 to 3 weeks, and larvae search for grasshopper egg cases.


• After feeding on an egg case, the larva molts and becomes fairly inactive but continues to develop and feed on the grasshopper eggs.

Host Range:

• Wide host range including: alfalfa, clover, soybean, potato, and tomato.

Injury & Damage:

• Most damage occurs as a result of adults feeding on foliage, but some pod and flower feeding may occur.


• Damage is usually confined to small areas

Monitoring:

• Visual counts


• Sweep nets


• Drop cloths

Management:

• Insecticides labeled for management of adults.