Diabrotica undecimpunctata

The three primary types of cucumber beetles are the spotted cucumber beetle, the banded cucumber beetle (Diabrotica balteata), and the striped cucumber beetle (Acalymma vittatum).[3] In North America, the spotted and striped cucumber beetles are the most commonly encountered varieties.

The spotted cucumber beetle has three subspecies, each with a different common name:

• Diabrotica undecimpunctata howardi – spotted cucumber beetle or southern corn rootworm[4]
• Diabrotica undecimpunctata tenella – western cucumber beetle[5]
• Diabrotica undecimpunctata undecimpunctata – western spotted cucumber beetle[6]

In the adult form, it eats leaves of many crops, including squash, cucumbers, soybeans, cotton, beans, and corn. Adult beetles lay eggs in the soil near a cucurbit plant. In a lifetime, females can lay between 150-400 eggs. However, there have been cases in which females have surpassed this quota, with some laying a total of 1,200 eggs.[7] The eggs hatch around mid spring and take 6–9 days to hatch under favorable conditions.[1] In some cases, specifically when the climate is at a lower temperature, eggs can take 30 days to hatch.[8] The ideal soil for egg survival is moist.[8] The larval stage lasts around 2–3 weeks[1] and the larvae are yellowish and wormlike.[9] After the larval stage insects become pupae, this stage lasts for 6–10 days.[10] The pupae measure around 6.25 millimeters in length and 3.5 millimeters in width. They feature a pair of robust spines located at the end of their abdomen, along with smaller spines on the upper side of their other abdominal segments.[11] After 6–10 days the adult beetle emerges. Adult beetles are greenish-yellow with six large black spots on each elytron. They are about 0.5 cm long.[12] In the summertime, adults usually have a lifespan of 60 days, while in winter, they can survive for as long as 200 days.[11]

This species is found throughout southern Canada, the continental USA, and the central highlands of Mexico,[13] but is particularly widespread throughout the southern states.[14]

During mating, the male spotted cucumber beetle positions himself on top of the female. Frequently, the female will make efforts to dislodge him. If the male manages to maintain his position despite the female's attempts, he will commence a gentle stroking of the female's antennae, eyes, and prolegs using his own antennae. This behavior is commonly referred to as 'antennal stroking.' [15]

Before accepting a reproductive partner, a female spotted cucumber beetle may mate with up to 15 males.[16]

Adult Spotted Cucumber beetles consume over fifty different types of crops and wild plants, including corn, peanuts, beans, apples, cherries, clovers, lettuce, potatoes, and more. Spotted Cucumber Beetles are classified as generalist feeders, which means they consume a wide variety of foods, however they often prefer cucurbits (plants belonging to the gourd family).[17]

The Spotted Cucumber Beetle has many natural prey. Of those, carabid beetles and wolf spiders are known to eat the Spotted Cucumber Beetle. Research has indicated that the presence of these natural foes in cucumber and squash fields leads to a decrease in Spotted Cucumber Beetle populations.[18] There are a variety of Vertebrates who are entree to the Spotted Cucumber Beetle: birds, mice, bats, and toads. The eggs of the beetle are consumed by certain predators, namely spiders, ground beetles, ants, and crickets.[19]

• Data related to Diabrotica undecimpunctata at Wikispecies
• Media related to Diabrotica undecimpunctata at Wikimedia Commons
• "Diabrotica undecimpunctata howardi (DIABUH)[Datasheet]". Global Database. EPPO (European and Mediterranean Plant Protection Organization). 2021-09-09. Retrieved 2021-10-21.