This large praying mantis is Tenodera aridifolia. It is the largest praying mantis in the U.S. and is very common around the Duke Campus. This species was introduced from China into the Northeastern United States about 75 years ago in the hope of controlling the native insect pest populations. It is now the most common praying mantis in North Carolina. Tenodera has one generation per year. Eggs hatch in the spring and the larvae metamorphose to adults in the late summer and early autumn. We kept this particular specimen alive in the lab for two-and-a-half months by feeding it on cockroaches. During this time she laid eggs four egg clusters (see photo). The eggs are enveloped in a foam of proteins that hardens to a tough brown egg case. One of these egg batches hatched and a picture of a hatchling larva is shown as well. The egg cases can be purchased from certain garden suppliers for release in the home garden as a means of natural pest control.
(2) Triplehorn, C.A. and N.F. Johnson, Borror and Delong’s Introduction to the Study of Insects, 7th ed., (2005), Thomson Brooks/Cole.