Calosoma (Camedula) sponsa Casey, 1897

Calosoma sponsa Casey, 1897: 340 (type locality: Utah); holotype ♂ by monotypy in National Museum of Natural History, Washington (
Calosoma parviceps Casey, 1897: 341(type locality: Arizona); syntype in National Museum of Natural History, Washington (
Calosoma eremicola Fall, 1910: 91 (type locality: California, S. Clemente island); syntype in Museum of Comparative Zoology, Harvard University, Cambridge, Ma. (
Calosoma rugosipennis Schaeffer, 1911: 113 (described from California)
Calosoma hospes Casey, 1913: 45 (type locality: California, Coronado); syntypes in National Museum of Natural History, Washington (
Acamegonia peregrinatrix incerta Lapouge, 1924: 38 (described from Baja California) original material: description compatible with one specimen only, repository not stated
Calosoma (Carabosoma) glabratum ssp. sponsum; Breuning, 1927b: 103
Callitropa (Acamegonia) glabrata incerta Lapouge, 1932: 388
Camedula (s. str.) eremicola; Jeannel, 1940: 206
Calosoma (Camedula) eremicola; Gidaspow, 1959: 259
Calosoma (Camedula) sponsa; Gidaspow, 1959: 260
Calosoma (Carabosoma) eremicola; Erwin, 2007: 91
Calosoma (Carabosoma) sponsum; Erwin, 2007: 104

Length 16-19 mm. As happen with glabratum and peregrinator sponsa is characterized by the presence of setae on the metatrochanters. It can be easily identified not only by the small size, by the only slightly transverse pronotum, and by the elongated elytra but also by the slender shape of male's copulatory organ, with a distinctly thin and elongated apex.
Breuning (1928a: 103) considered it a subspecies of C.glabratum as he did with C. peregrinator, and C. eremicola as a synonym. Vice versa, Jeannel (1940) thought that the C. sponsa of Casey (1897) was a reduced size form of C. peregrinator, while C. eremicola was a valid species to which could apply the diagnosis of Calosoma (Carabosoma) glabratum ssp sponsum of Breuning. Gidaspow (1959) who examined the type of C. sponsa, considered it a valid species, distinct from C. peregrinator. Also C. eremicola, according to Gidaspow should be a valid species, from which C. sponsa would be distinct by the more slender body shape, and by apex of male's copulatory organ that should be slightly more curved.
Gidaspow that did not know the type of C. eremicola, gave for it a diagnosis that has many points of contact with that of Jeannel. Some differences, such as the possibility of some specimens having a more transverse pronotum and a more squat body shape are due to both the individual variability that to the possibility of confusion with small size specimens of C. parvicolle, which has a similar male's copulatory organ In this regard Jeannel had already noted that Calosoma rugosipennis Schaeffer, 1911 that Breuining and Gidaspow considered conspecific with C. sponsa should instead be attributed to C. parvicolle.
The differences between C. sponsa and C. eremicola are very slight, and, going back to the opinion of Breuning, it seems preferable to consider the two taxa as a single species, to which, obviously, the name sponsa should be applied.
The type of sponsa comes from Utah, the type of parviceps from Arizona and the one of peregrinator incerta from Baja California in Mexico. All the other quotes reported in the literature are of places in California to which Gidaspow (1959: 259) added New Mexico, Erwin (2007: 9) Nevada, and Bousquet (2012: 235) Colorado.
Note that, Breuning (1927b: 103), corrected the name of the species in sponsum. In some case subsequent authors accepted this correction, but it is incorrect because the noun "sponsa" do not need to agree in gender with the name of genus Calosoma (International Code of Zoological Nomenclature, art. 31.2.1) and therefore remains valid the name given by Casey.

Examined specimens and literature’s data
Mexico. Baixa California: Enseada (sub eremicola, Gidaspow, 1959: 259)
United States. Arizona: Maricopa County, South Mountain Regional Park (, Cochise (one syntype, NMNH); California: California (sub eremicola MNHN), San Bernardino County (AMNH), Mono County (AMNH), Indipendence, Big Pine (Gidaspow, 1959: 260), Inyo Co., Santa Catalina Island (Gidaspow, 1959: 260), Santa Barbara island (, San Clemente Island (Breuning, 1928a: 107), North San Clemente island (, Coronado, Imperial County, Algodones Dunes (; Colorado: Montezuma Co. (sub eremicola, Bousquet, 2012: 235); New Mexico: Faywood (sub eremicola, Gidaspow, 1959: 259), Bernalillo County, Albuquerque (; Nevada: Esmeralda Co., Washoe co. (sub parviceps, La Rivers, 1946: 136); Churchill Co., Mineral Co, Pilot Mountains (Gidaspow, 1959: 260); Utah: Millard Co., Kern Karns (Bousquet, 2012: 236), Grand county, Emery county, Tooele County (

Notes: Winged. It has been found from 100 to 1200m of altitude. Adults seem to be active in March - August (Larochelle & Larivière, 2003: 183)

Calosoma (Camedula) sponsa
Casey, 1897
California, E. Dongé (sub. eremicola Fall 1910)
(coll. Muséum National d'Histoire Naturelle, Paris)
Calosoma (Camedula) sponsa
Casey, 1897
California, Mono county, White Mts., Crooked creek, 20.VI.1961DH Miller
(coll. American Museum of Natural History, New York)
Calosoma (Camedula) sponsa
Casey, 1897
California, San Bernardino county, Kane Spring near Newberry, 27.III.1964, E. Ball jr. lgt.
(coll. American Museum of Natural History, New York)

updated December 13 2022