Calosoma (Orinodromus) elgonense Burgeon, 1928

Carabomorphus elgonensis Burgeon, 1928: 432 (type: mont Elgon; Musée Royal de l'Afrique Central, Tervuren)
Calosoma (Carabomorphus) alinderi Breuning, 1928: 91
Calosoma (Carabomorphus) elgonense Breuning, 1928: 93
Carabomorphus (Orinodromus) alinderi Lapouge, 1932: 398
Carabomorphus (Orinodromus) elgonensis Lapouge, 1932: 398
Orinodromus (Elgonites) elgonensis Jeannel, 1940: 146
Orinodromus (Elgonites) elgonensis subsp. malleatus Jeannel, 1940: 147 (type: mont Elgon, versant occidental; British Museum of Natural History, London)

Length 10-16 mm. Two species (or perhaps two forms of the same species) are found on Mount Elgon: elgonense and kenyense. Both of them are characterized by well developed rear lobes of pronotum but missing the setae. For them Jeannel (1940) created the subgenus Elgonites.
The populations or individuals inside the populations of this species vary greatly and have been variously named and differently interpreted.
In fact, on Mount Elgon we find individuals where the sculpture of elytra consists of primary intervals raised in continuous ridges and secondary and tertiary ones replaced by disordered punctuation (elgonense s. str). and other smaller size individuals where the sculpture of elytra is affected by more or less deep transverse depressions, which may go to obliterate the primary intervals.
Based on the alleged coexistence of these individuals Jeannel (1940: 147) considered synonymous alinderi and elgonense, but in the same time, further complicating the issue, has distinguished at sub specific level the specimens collected on the western side of the crater in Uganda (malleatus), emphasizing some weak morphological differences (less protruding shoulders, sculpture more accentuated, smaller size).
In the case of elgonense, if really so different individuals coexist in the same population, their morphological differentiation appears to be due to a high degree of individual variability, variously influenced by changes in micro-habitats, rather than due to issues of protracted geographical isolation of populations. Their morphological differentiation could be interpreted not as a starting point of speciation, as has been conjectured by Jeannel (1961: 139) in another case (the case of Elgonotrechus of the same mount Elgon), but instead could be considered as the reversible adaptation of phenotypes extremely sensitive to the changing environmental conditions, typical of the high altitude habitat (Brühl 1977: 239).
For this reason, at the moment and for the purposes of this study, we do not think these populations should be considered as subspecies.
elgonense, interpreted in this way, is found along the slopes of the crater of Mount Elgon.

Examined specimens
Kenya: Mt Elgon 4000-4200 m (SB); Mt Elgon, eastern slopes, 3350-3800 m (holotype elgonense, RMCA; AVT, EM, MNHN, SB).
Uganda: Mt Elgon, Mudangi, 3350 m (paratype malleatus, RMCA); Mt. Elgon, on the way to Wagagai peak (SB)

Notes: Wingless. It lives in alpine meadows, from 3300 to 4200m. The adults were found in activity in very humid months, between December and February, in April and in July, the first dates corresponding to the beginnig of the two rainy periods, and the last one corresponding to the most fresh and humid period.

Calosoma (Orinodromus) elgonense
Burgeon, 1928
British East Africa, Elgon District, IV.V.1914, Dr. Bayer
(holotype)
(coll. Musée Royal de l'Afrique Central, Tervuren)
Calosoma (Orinodromus) elgonense
Burgeon, 1928
Uganda: Mt. Elgon, on the way to Wagagai peak
28.IV.2009 P. Malec

Calosoma (Orinodromus) elgonense
Burgeon, 1928
Kenya: Mt Elgon vers. Est, 3.000-3.500 m. 7.VII.1991
Casale & Vigna leg. (coll. Vigna Taglianti)

Calosoma (Orinodromus) elgonense
Burgeon, 1928
Uganda: Mt Elgon, Mudangi, 11000 ft, 11.VIII.1934, J. Ford
paratype subsp. malleatus Jeannel,
(coll. Musée Royal de l'Afrique Central, Tervuren)
Calosoma (Orinodromus) elgonense
Burgeon, 1928
Kenya: Mt Elgon N.P., 4000m, 16.IV.2005
Calosoma (Orinodromus) elgonense
Burgeon 1928
Kenya: Mt Elgon N.P., 4000m, 16.IV.2005

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