Calosoma (Chrysostigma) calidum (Fabricius, 1775)

Carabus calidus Fabricius, 1775: 237 (described from America); lectotype ♂ in Natural History Museum of Denmark, Copenhagen (Lindroth, 1961: 50)
Calosoma calidum Fabricius, 1801: 211
Chrysostigma calidum Kirby, 1837: 19
Calosoma lepidum LeConte, 1844: 201 (described from Missouri); syntype in Museum of Comparative Zoology, Harvard University, Cambridge, Ma. (
Calosoma mexicanum Géhin, 1885: 67, note 72 (described from: Mexique, Cordoba) holotype ♂ designated by Deuve (1978: 250) by monotypy in Muséum National d'Histoire Naturelle, Paris [examined]
Calosoma calida stellata Casey, 1897: 344 (described from Lake Superior); syntype in National Museum of Natural History, Washington (
Calosoma calida expansa Casey, 1897: 344 (described from Keokuk, Iowa); syntype in National Museum of Natural History, Washington (
Calosoma calida laticollis Casey, 1897: 344 (described from Las Vegas), syntype in Nationa l Museum of Natural History, Washington (
Calosoma comes Casey, 1920: 156 (described from North West Territ.); holotype ♂ by monotypy in National Museum of Natural History, Washington (
Calosoma concreta Casey 1920: 157 (described from Lake Superior); holotype ♂ by monotypy in National Museum of Natural History, Washington (
Calosoma (Carabosoma) calidum Breuning, 1928: 84
Calosoma (Carabosoma) calidum ssp. stellatum Breuning, 1928: 84
Calosoma (Chrysostigma) morrisoni ssp. mexicanum Breuning, 1928: 86
Callisthenes (Chrysostigma) lepidum Lapouge, 1932: 381
Callisthenes (Chrysostigma) lepidum mexicanum Lapouge, 1932: 381
Callisthenes (Chrysostigma) lepidum ocellatum Lapouge, 1932: 381 (type locality: Canada méridional, Etats Unis)
Callisthenes (Chrysostigma) lepidum stellatum Lapouge, 1932: 381
Callisthenes (Chrysostigma) lepidum laticolle Lapouge, 1932: 381
Callisthenes (Chrysostigma) lepidum concretum Lapouge, 1932: 381
Chrysostigma calidum Jeannel, 1940: 164
Chrysostigma Morrisoni var. mexicanum Jeannel 1940:165
Calosoma (Chrysostigma) lepidum Gidaspow, 1959: 264
Calosoma (Chrysostigma) calidum Gidaspow, 1959: 265
Calosoma (Chrysostigma) concreta Gidaspow, 1959: 266
Callisthenes (Chrysostigma) calidus Erwin, 2007: 75
Callisthenes (Chrysostigma) lepidus Erwin, 2007: 78

Length 17-30 mm. calidum is characterized by a sculpture of elytra of "homodyname" type in which the intervals are of the same height and width, with dotted striae and intervals interrupted by transverse wrinkles.
The pronotum is a little restricted to the base with broad rear lobes. The color of the upper body is greenish brown, on which stand out large foveae with a cupric bottom, in correspondence with the primary intervals but that generally cover at least part of the adjacent ones.
C. calidum is a relatively variable species and this explains why after the many synonyms discussed by Breuning (1927) and accepted by Jeannel (1940), Gidaspow (1959) has re-evaluated as good species Calosoma (Chrysostigma) concreta, which however, has not been considered valid by later authors.
As for C. lepidum, it has been considered synonymous with C. calidum by Breuning (1928: 84) and Jeannel (1940: 164), but re-evaluated by Gidaspow (1959: 264) as a good species, followed by the subsequent authors. C. lepidum should have shorter elytra, and its pronotum should be a little narrower at the base with small rear lobes, but in fact C. lepidum can be more easily spotted by its steadily smaller size (17 - 19mm), and by the color of the upper body reddish-brown, with small foveae with green bottom. The penis is the same than C. calidum, but, Gidaspow point out, that it has a thinner ligule. The wings are normally formed but, by emphasizing some peculiarities of their structure, Lindroth (1961: 51) expresses doubts about its ability to fly, unlike C. calidum which he considers a good flier. However, we think that such morphological differences as the ones we described, by their nature, may also be due to individual variability, possibly influenced by climatic conditions at the time of the various stages of development. The two forms coexist in the northern part of the distribution area, and bearing in mind the variability of characters of the Calosoma species, it seems preferable to follow the more conservative position taken by Breuning and Jeannel.
As for C. mexicanum, Breuning (1928: 86), without knowing the type, but on the basis of the description and of the figure given by Géhin (1885: 67, note 72, table IX), considered it as a subspecies of C morrisoni. Jeannel (1940:165) and all more recent authors followed this opinion. The type examination in MNHN, however, easily allows for recognizing a specimen of C. calidum, albeit somewhat aberrant and with incorrect locality data. Moreover, Breuning identified some Calosoma specimens in its possession and coming from Nevada as C. morrisoni mexicanum. These specimens, that according to Breuning should be characterized by slightly pronounced intervals and large, greenish primary pits ("the size of the ones of C. calidum"), probably should also be referred to C. calidum.
Finally, Lapouge (1930:43) believed that he could identify in the collection of Fabricius existing at Natural History Museum of London the types of C. calidum in two specimens of of C. rugosum (=C. chlorostictum). Consequently, in his opinion, the name calidum would not therefore be usable for the American species and should be replaced by lepidum.
C. calidum, spreads through southern Canada and northern United States, rarely occurs in the southern States and it is absent in the south-western ones. Erwin (2007: 75) cites C. calidum also from Puerto Rico.

Examined specimens and literature’s data
Canada. Alberta: Coaldale (sub lepidum, EM), Medicine Hat (sub lepidum, AMNH, SB), Calgary, Brooks, Tilley (sub lepidum, Gidaspow, 1959: 285), Banff National Park, Ralston, Calgary, Onefour, Ranchville, Suffield (sub lepidum, UASM), Calahoo, Edmonton, Slave Lake, Castor, Leduc, Blackfalds, Mundare, Brooks, Chisholm, Ellerslie, Morinville, Cypress Hills, Medicine Hat, Athabasca, Morinville Robinson, (UASM), Hilda, Tilley, Brooks, Coaldale, Lethbridge, Monarch, Retlaw, Calgary (sub lepidum, Lindroth, 1961: 51), Elk Island National Park (; British Colombia: Rolla, North Pine, Fort St John (Lindroth, 1961: 51); Manitoba: Virden (SB), Aweme (sub lepidum, Gidaspow, 1959: 285), Glenboro (sub lepidum, Lindroth, 1961: 51), Alexander, Winefred Lake, Richer, Birds Hill Provincial Park, Morden (UASM), Park (South) (, Kamloops (, Clear lake, Riding Mountain N.P. (Lindroth, 1961: 51); New Brunswick (Webster, 2016: 392); Newfoundland (Jeannel, 1940: 164); Northwest Territories: Norman Wells (Lindroth, 1961: 51); Nova Scotia: Cape Breton Island (Lindroth, 1961: 51) Halifax (; Ontario: Nipigon, Attawapiskat (Lindroth, 1961: 51), Nipissing ( , Algoma District (, Flamborough (, Erin, Prince Edward Island, St Ignace Island, Kawartha Lakes, Falconbridge (; Québec: Parc National de la pointe-Taillon ( ), San Jean de Matha (SB), Charlesbourg (, St-Raymond ( 854602); Saskatchewan: Pike Lake (SB), Usborne ( 29872055), Tisdale, Whitefox (Lindroth, 1961: 51), Prud'homme (sub lepidum, UASM), Great Deer, Craven, Richmond, Bounty, Eagle Hill Creek, Saskatoon (sub lepidum, Lindroth, 1961: 51).
Saint Pierre et Miquelon (France) (Jeannel, 1940: 164)
United States. Colorado: Lyons (, Denver (Breuning, 1928: 86); Connecticut, Delaware, District of Columbia, Georgia (Burgess & Collins, 1917: 98); Illinois: Chicago (SB), West Marion Precinct (; Indiana (Burgess & Collins, 1917: 98); Iowa: Keokuk (syntype calida expansa, NMNH) Pottawattamie County (; Kansas: Topeka, Riley co. (sub concreta; Gidaspow, 1959: 266), Elmendaro (; Kentucky (Burgess & Collins, 1917: 98), Maine: Hope (, Somerset County ( 631539); Maryland: Plummers island (Erwin, 2007: 75); Massachusset (Burgess & Collins, 1917: 98), Nantucket (; Michigan: Washtenaw co. (EM), Boyne City, Elmira, Oscoda County (; Minnesota: St. Louis County (; Missouri (syntype calidum var. lepidum, MCZ), Saint Joseph (sub concreta; Gidaspow, 1959: 266); Montana: Bearpaw, Havre (=Harve), Helena, Dutton (sub lepidum, Gidaspow, 1959: 265), Carbon County (; Nebraska (Burgess & Collins, 1917: 98); Nevada: Las Vegas (syntype calida laticollis, MCZ), Hiko range (Breuning 1928a: 87, sub morrisoni mexicanum); New Hampshire, New Jersey (Burgess & Collins, 1917: 98); New Mexico: Valles Caldera (; New York: Ithaca (UASM); North Carolina (Burgess & Collins, 1917: 98); North Dakota: Cass county, Fargo, Hettinger county, Dunn county (UASM); Ohio, Pennsylvania (Burgess & Collins, 1917: 98); South Dakota: Southwest Meade ( 778608); Tennessy, Vermont, Virginia (Burgess & Collins, 1917: 98); Washington: Steilacoom (Breuning, 1928: 84); Wisconsis: Bayfield (NMNH), Spring Green, Delton (; Wyoming: Sheridan county (

Notes: C. calidum is diurnal and nocturnal, active in sunshine or sheltering under debris or stones. It can be found in lowlands and midlands up to 1300m altitude. It lives in a variety of habitats: on open ground as pastures, tilled fields, vacant lots or in open forests. Adults and larvae are terricolous predators of caterpillars and other insects that sometime can damage crops.
Adults, living near a water body, have been seen, in case of danger, taking refuge in the water. According to the oldest report (Moore, 1933) a specimen, on the beach of Lake Michigan, sought refuge under a submerged stone and remained there without damages for nineteen minutes. Also more recent observations (Landry 1976) confirmed that Calosoma calidum, if threatened, enter freely under water and can remain submerged a couple of minutes.
In the northern part of its aerea of diffusion, C. calidum has been found active mostly in May – July, , overwintering in the colder season. (Lindroth, 1961: 51), but in the suthern areas it can be observed in activity from April to December
The description of larva in all stages and pupa has been given by Burgess (1896: 426) and Burgess & Collins (1917: 98).

Calosoma (Chrysostigma) calidum
(Fabricius, 1775)
Canada: Québec, San Jean de Matha, 1.VII.76, Garneau
Calosoma (Chrysostigma) calidum
(Fabricius, 1775)
Canada: Manitoba, 18 km. E. of Virden, 27.6.08, Lawton
Calosoma (Chrysostigma) calidum
(Fabricius, 1775)
Nebraska (Typus of Calosoma lepidum)
(coll. and photo: Museum of Comparative Zoology,
Harvard University, Cambridge, Massachusetts, USA)
Calosoma (Chrysostigma) calidum
(Fabricius, 1775)
Canada: Alberta, Medicine Hat, VI, 1922
(sub Calosoma (Chrysostigma) lepidum)
Calosoma (Chrysostigma) calidum
(Fabricius, 1775)
Mexique (type of Calosoma mexicanum)
(coll. Muséum National d'Histoire Naturelle, Paris)

updated Aug 4 2019