Origin:
These are native beetles in North America, with C. nitida occurring in the eastern U.S. and C. mutabilis occurring in the western U.S. and Mexico. Both species may occur in Texas.
Biology:
Two very similar species of Cotinis occur in the southern U.S. and Mexico, C. nitida and C. mutabilis. Both feed widely on thin-skinned fruits such as figs, peaches, and grapes as the adult beetle, and the larvae feed on decomposing plant matter. They can be a pest of turf as the larvae burrow through the soil, but they do not feed on the plant roots. Adult burrowing can create dirt mounds that are unsightly and damaging to mowers. Older larvae overwinter and pupate in mid-spring, with adults emerging in early summer.
Identification:
The adult beetles are very distinctive, being about 1 inch long and with the head, thorax, and abdomen all a dull, dark metallic green color, except for yellowish-tan bars along the sides of the abdomen. Cotinis nitida has much greater amounts of this tan coloring on the sides and top of the elytra, as well as bars along the sides of the thorax. The legs of nitida are also tan while the legs of mutabilis are shiny green. Their antennae are the “lamellate” antennae of scarabs, with the first half composed of short segments and the final few segments greatly elongated on one side to form almost a fan-like appearance.
Characteristicts Important to Control:
Avoiding large applications of manure fertilizer to turf will help to prevent the beetles from choosing that site for their larvae. Applications of contact insecticides to fruit trees that are infested will kill adult beetles, as will granular applications of contact insecticides to turf.
