Species Calosoma sayi - Black Caterpillar Hunter

Synonym: Calosoma alternans

25-28 mm

Large, black, with prominent gold or red punctures and blue or green margins of elytra. (These are not prominent on cursory inspection--the beetle appears all black.) Resembles C. calidum but larger (25-28 mm for sayi vs. 16-27 mm for calidum). C. sayi is more southern in distribution, apparently replacing (?) it in southeastern United States. Quoting from Ciegler, Ground Beetles of South Carolina, p. 27 (1):

4(1) Pronotum with setigerous puncture near hind angle; lateral raised bead of pronotum sharply defined inwardly for its entire length---> C. sayi

Pronotum without basal setigerous puncture but with usual lateral one at midline; lateral bead obscure, at least basally ---> 5 (C. externum, C. calidum)

Widespread North American range is defined by quadrangle NY, FL, AZ, MN. Also occurs in Cuba, Jamaica, Hispaniola, Central America.

Deciduous forests, grasslands, cultivated land, beaches.

Spring-fall. March-November (South Carolina). April-October (North Carolina).

Predatory on other insects, especially caterpillars.

Eggs are laid singly in soil. Larvae live in soil (predatory?), and overwinter. Adults may live two to three years. Adults come to lights.

Other Calosoma species, esp. Calosoma calidum.

Ciegler, p. 27 (1)

Brimley, p. 116, lists C. sayi for much of eastern North Carolina, lists C. calidum only from mountains of that state. (2)

Account at Digital Arthropods

Image at Clemson University

Florida Nature account of Calosoma calidum may actually show C. sayi.

Key to Florida Ground Beetles

Abundant in the entomology collection at North Carolina State University.

Beetles of Florida--lists this and not C. calidum.