Colorado Beetle

• It has evolved resistance to more than fifty different insecticides, often within a few years of their introduction; the first case, to DDT, was documented in 1952.
• Its enormous fecundity is what allows this: each female leaves such a large genetic pool that selection almost always finds something to act on.
• A single adult can eat about 10 cm² of leaf a day, and one individual consumes around 40 cm² over its whole larval stage.
• Its range already covers some 16 million km² and is still growing.
• It played a decisive part in the birth of the modern pesticide industry: hundreds of compounds were tested against it.

Skeleton type

Invertebrate - chitin exoskeleton (insect)

Habitat and environment

Potato fields and other nightshade crops across North America, Europe and Asia; it overwinters buried in the soil in diapause

Size at birth

The larvae reach 12 mm by the end of the fourth instar; the eggs are laid in clusters of 20 to 60

Gestation / incubation

The eggs hatch in 4-9 days; the larvae develop in 18-21 days through four instars and the pupa lasts 5 to 10 days; the full cycle can close in 21-30 days

Litter / clutch size

From 300 to 500 eggs per female over 4-5 weeks, in groups of 20 to 60 on the underside of the leaves; some studies record up to 724

Sources consulted: https://es.wikipedia.org/wiki/Leptinotarsa_decemlineata; Oklahoma State University Extension; University of Georgia IPM; LSU AgCenter; University of Florida; University of Florida, ficha Colorado potato beetle; Cornell / Maine DACF

Best time: The overwintering adults emerge from the soil between April and late May; one to three generations a year depending on the latitude