Calosoma (Chrysostigma) tepidum LeConte, 1852

Calosoma tepidum LeConte, 1852: 199 (type locality: "Oregon"); syntype (Oregon, Washington county) in Museum of Comparative Zoology, Harvard University, Cambridge, Ma. (https://mczbase.mcz.harvard.edu/)
Calosoma irregulare Walker, 1866: 312 (described from Iles Vancouver) syntype possibly in Natural History Museum, London (Bousquet, 2012: 243)
Calosoma tepida caelator Casey, 1913: 61 (type locality: Idaho, Coeur d'Alene); holotype ♂ by monotypy in National Museum of Natural History, Washington (https://collections.nmnh.si.edu/)
Calosoma tepida indigens Casey, 1913: 61 (described from Oregon); syntype in National Museum of Natural History, Washington (https://collections.nmnh.si.edu/)
Calosoma pellax Casey, 1920: 160 (type locality: "probably Oregon"); holotype ♂ by monotypy in National Museum of Natural History, Washington (https://collections.nmnh.si.edu/)
Calosoma semicuprea Casey, 1920: 161 (type locality: "probably Rocky Mountains"); holotype ♂ by monotypy in National Museum of Natural History, Washington (https://collections.nmnh.si.edu/)
Calosoma cogitans Casey, 1920: 161 (described from Stockton, Utah); lectotype ♀ in National Museum of Natural History, Washington (https://collections.nmnh.si.edu/)
Calosoma (Chrysostigma) tepidum Breuning, 1928: 87
Callisthenes (Chrysostigma) tepidum Lapouge, 1931: 381
Callisthenes (Chrysostigma) tepidum irregulare Lapouge, 1931: 381
Callisthenes (Chrysostigma) tepidum cogitans Lapouge, 1931: 381
Chrysostigma tepidum Jeannel, 1940: 165
Calosoma (Chrysostigma) tepidum Gidaspow, 1963: 263
Callisthenes (Chrysostigma) tepidus Erwin, 2007: 82


Length 15-24 mm. It is characterized by a short, squat form, with posteriorly narrowed pronotum and elytra widened sharply in the back. The sculpture of elytra consists of irregular intervals, often confluent and dissolved in rough granules. The primary intervals are not distinct in shape or height, but are characterized by the presence of cupric foveae. The color of the upper body is uniformly blackish.
It is relatively common from British Colombia to Oregon, Utah and California, but possibly the species spreads through a more wide area. Breuning (1928a: 89) doubtfully referred a quote from Colorado and Calosoma tepida caelator that must be considered synonym of C. tepidum has been described by Casey from Idaho. Finally, Gidaspow (1963: 264) and Erwin (2007: 82) claim it is present in all the western states along the slopes of the Rocky Mountains.

Examined specimens and literature’s data
Canada.. Alberta : Medicine Hat (OSUC www.gbif.org); British Colombia: Cilcotin (SB), Salmon Arm (AMNH), Is Vancouver (MCZR, UASM), Whitty's Lagoon, Haines Point, Invermere, Osoyoos, Oliver, Princeton (UASM), Victoria (EM), Cranbrook, Creston, Kamloops, Golden (Lindroth, 1961: 52), Okanagan-Similkameen, Vernon (www.inaturalist.org/)
United States.: Arizona (Bousquet, 2012: 244); California: Del Norte co., Sacramento (Breuning, 1928a: 89), Raymond (OSUC www.gbif.org); Colorado (Breuning, 1928a: 89), Eagle County, Gunnison County (www.inaturalist.org); Idaho: Coeur d'Alene (La Rivers, 1946: 136), Nez Perce co. (www.gbif.org); Montana: Missoula County (www.inaturalist.org); Nebraska (Bousquet, 2012: 244); Nevada: Washoe co. (La Rivers, 1946: 136); Oregon: (NMP), Oregon City (Breuning, 1928a: 89); Utah: Salt Lake, 1400m (MNHN), Ogden (La Rivers, 1946: 136), Stockton, Cisco (Breuning, 1928a: 89), Bingham, Wayne co. (www.gbif.org); Washington: (NMP), Chelan co., Yakima co. (www.gbif.org); Wyoming: Shoshone National Forest (www.inaturalist.org).

. Notes:Winged, but with underdeveloped wings probably unfit for flight. It is found from sea level up to about 1500m. above sea level, in arid grasslands and in cultivated fields, it hunts on the ground and, like all other species of the genus, feeds on caterpillars and grasshoppers. The adults are active in May-June up to to August according to Larochelle & Larivière (2003: 184).

Calosoma (Chrysostigma) tepidum
LeConte, 1852
Canada: British Colombia, Cilcotin
15.V.1929, G.J. Spencer leg.
Calosoma (Chrysostigma) tepidum
LeConte, 1852
Canada: British Colombia, Salmon Arm, VIII.1932 H Leech leg.
(coll. American Museum of Natural History, New York)

updated June 27 2020

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