Jeffrey Hahn, University of Minnesota Asst. Extension Entomologist
An unusual insect, a northern mole cricket (Neocurtilla hexadactyla), was submitted to the entomology department in August. This insect was found by a homeowner in their yard in North Branch (Chisago county) in east central Minnesota. Northern mole crickets are found throughout the eastern U.S. in low lying moist areas, e.g. along the margins of lakes and streams. They are rarely found in home lawns and are not considered to be a pest in Minnesota.
This brown insect grows up to 1 1/4 - 1 1/3 inches long, has moderate length antennae and short wings that only extend about half way down its abdomen. What is particularly distinctive about this insect is its stout, mole-like front pair of legs which are modified for digging (called fossorial). They have four dactyls (claws) on their tibia which distinguishes them from closely related mole crickets. Despite their ungainly appearance, northern moles crickets are capable of flight, flying at dusk.
They spend essentially their entire life underground where they feed on grass. If a northern mole cricket is exposed, its first reaction is to dig back down into the soil.
They take two years to develop into adults. Females lay eggs in spring in chambers in the soil. The immature nymphs develop slowly and spend the first winter as nymphs. They eventually mature the second year wintering as adults.
A northern mole cricket is a relatively uncommon insect in Minnesota, but even less commonly noticed by people due to its secretive habits. Interestingly, a number of eastern states also reported encountering this insect this summer in instances when they normally do not. It will be interesting to see if this a future trend or if this year was just a good year for northern mole crickets.