Calosoma (Chrysostigma) semilaeve LeConte, 1852

Calosoma semilaeve LeConte, 1852: 199 (described from "San Diego", California); syntype in Museum of Comparative Zoology, Harvard University, Cambridge, Ma. (
Calosoma semilaeve davidsoni Casey, 1914: 33 (described from Alameda, California); syntypes in National Museum of Natural History, Washington (
Calosoma semilaeve adjutor Casey, 1920: 162 (described from Alameda, California); syntype in National Museum of Natural History, Washington (
Calosoma (Carabosoma) semilaeve Breuning, 1928: 111
Callitropa (Acamegonia) semilaevis Lapouge, 1931: 388
Chrysostigma semilaeve Jeannel, 1940: 168
Calosoma (Chrysostigma) semilaeve Gidaspow, 1959: 271
Callisthenes (Chrysostigma) semilaevis Erwin, 2007: 81

Length 20-27mm. C. semilaeve, as C. affine and C. simplex, has an elytral sculpture with flatten intervals and striae indicated by superficial punctures only. The color in the three species is dull black. C. semilaeve is easily distinguished by the strongly transverse pronotum and by the sculpture of elytra with clearly scaly intervals, especially at humeri.
It lives in the southwestern United States: Arizona, California, Idaho, New Mexico, Oregon, Utah, and it should be present in Guadalupe island, off the coast of Baja California (Mexico).
Following its importation as a potential agents of biological control into Hawaii, C. semilaeve have been also cited as part of the entomological fauna of the Islands ( /HBS/checklist).

Examined specimens and literature’s data
Mexico. Baja California: Guadalupe island (Horn, 1876: 199)
United States. Arizona, Pima County (, Maricopa County, Gila County (, Paradise Valley, Huachuca Mountains (; California: Alameda co. (syntypes of semilaeve davidsoni and semilaeve adjutor; NMNH), San Josè (Burgess & Collins 1917: 90), Hollywood, Whittier, Compton (Burgess & Collins 1917: 91), Los Angeles co. (SB), La Puente (EM), Orange County (AVT, EM, SB), San Diego County, (, Mission Trails Regional Park (, Algonodes Dunes, (, Rancho Bernardo, Lake Hodges, Borrego Springs, (, Anza-Borrego Desert State Park (, Imperial County, Glamis; Ventura County; Kern County (, Wildcat Canyon (; Hawai (; Idaho: Camas co. (Burgess & Collins 1917: 91); New Mexico: Ramon, Lincoln county (UASM), Bandelier (; Oregon (Jeannel, 1940: 169); Utah (Gidaspow, 1959: 271)

Notes: Winged. It is found from lowlands to midlands up to 1300m altitude, on open ground and tilled fields. It is diurnal as well nocturnal and feeds on caterpillars, cutworms (Elateridae larvae) and other ground-inhabiting larvae (Burgess & Collins 1917: 91). Specimens of C. semilaeve were imported from Ventura County, California, and liberated at Waikii, Hawaii in 1923 in order to control the infestations of Lepidoptera Noctuidae (Funasaki & al., 1988: 113).
The adults are active in April-May but they can be found up to December.
A brief description of larval stages can be found in Burgess & Collins (1917: 92).

Calosoma (Chrysostigma) semilaeve ♂ LeConte, 1852
United States: California, Orange co., Balsa Chico beach, V.1983, Taylor leg. (coll. Vigna Taglianti)
Calosoma (Chrysostigma) semilaeve ♀ LeConte, 1852
United States: California, Los Angeles, Santa Monica mountains, 16.IV.83 Baierl lgt.

last review April 18 2019