Mantids are some of the most distinctive and well recognized insects whose most striking feature is their grasping front legs, well-designed for grabbing and holding prey. To support the prominent forelegs, the prothorax of mantids is very elongated. Mantids also have the remarkable ability to easily turn their triangular heads so that they can see in all directions. At least six species of mantids can be found in Colorado including native mantids that are common in Colorado's eastern plains and southern areas. The most commonly encountered mantids, the European mantid and Chinese mantid, are introduced species. The Chinese mantid is commonly sold through nurseries and garden catalogs; however, few, if any, survive winters in Colorado. All mantids are predators, feeding on a wide variety of insects, including some pest species. Mantids survive winter as eggs. The eggs are laid in masses, sometimes numbering in the hundreds. These egg masses, known as oothecae are often insulated with a foamy material that may give them the appearance of a "packing peanut" and are attached to solid surfaces such as rocks, buildings, and dried plant stems. Eggs hatch in late spring (or earlier if kept in the warmth of a building). The minute young mantids feed on small gnats and other insects, sometimes cannibalizing other mantids emerging from the same egg mass. As they grow, they are capable of capturing increasingly larger prey, including grasshoppers, large flies, and bees. Following several molts, development is completed by late summer and the adults are present. Adult males are smaller and more slender than females. Among winged species males are much more likely to fly; females are incapable of flying after they have begun to swell with eggs. It is sometimes reported that the female eats the male during mating. This does sometimes occur and the male may even continue to mate more vigorously after decapitation; however, this cannibalistic behavior occurs infrequently and usually only if the female is starved. Egg cases of the Chinese mantid are commonly sold for control of garden pests. Although release of eggs may result in several of these statuesque predators developing within the garden, little pest management benefit can be expected. There are a couple of reasons for this--one is related to their non-selective feeding habits--essentially any moving arthropod of right size will be suitable prey. Although this may include an occasional grasshopper or other pest insect, most mantid prey includes various flies, gnats, bees and other non-injurious species. Furthermore, since mantids only have a single generation each year, they can not increase in numbers sufficiently rapidly to control a pest outbreak. Finally, the Chinese mantid rarely, if ever, successfully survives winters in Colorado, dying out in the cold dry winters. For more information see the fact sheet, Mantids of Colorado.

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