Calosoma (Chrysostigma) morrisoni Horn, 1885

Calosoma morrisoni Horn, 1885: 18 (described from Colorado; syntype in Museum of Comparative Zoology, Harvard University, Cambridge, Ma)
Calosoma (Chrysostigma) morrisoni Breuning, 1928: 86
Callisthenes (Chrysostigma) morrisoni Lapouge, 1931: 381
Chrysostigma Morrisoni Jeannel 1940:165
Calosoma (Chrysostigma) morrisoni Gidaspow, 1959: 270
Callisthenes (Chrysostigma) morrisonii Erwin, 2007: 79

Length 18-25 mm. C. morrisoni has the pronotum narrowed at the base with small rear lobes. The elytra in both sexes are short and conspicuously wide toward the apex, the sculpture is flattened, of homodynamic type, consisting in punctate striae with intervals slightly scaly, more so in the lateral parts of elytra. The foveae on the primary intervals, while small and shallow, have a copper bottom and so are clearly visible.
It is certainly present, though rare, in Colorado. However it has been often indicated present in a larger area of the south-western United States. In fact Breuning (1928a: 86) has cited it as C. morrisoni mexicanum from Nevada, Burgess & Collins, (1917: 106) suggested its presence also in South California and Gidaspow (1959: 270) referred that it has been found in New Mexico as well as in northern Mexico (Durango).

Examined specimens
United States. Colorado: Denver (AC), Hesperus (AMNH); Nevada: Hiko range (sub C. morrisoni mexicanum Breuning, 1928a: 86)

Notes: Winged. It can be found in uplands from 1500m to 1800m altitude, on dry open ground and sand dune. Adult have been found active in April -May (Erwin, 2007: 79).
The species is named after Herbert Knowles Morrison [1854-1885] a professional insect collector that travelled all across the United States in order to enrich his collection of Butterflies.

Calosoma (Chrysostigma) morrisoni ♂ Horn, 1885
United States: Colorado, Denver, 2.V.1949
(coll. A. Casale)
Calosoma (Chrysostigma) morrisoni ♀ Horn, 1885
United States: Colorado, Hesperus 8100 ft., 5.VI.39, Rotger
(coll. American Museum of Natural History, New York)