Calosoma (Carabomorphus) masaicum Alluaud, 1912

masaicum and catenatum are both characterized by the disappearance of striation of elytra at the area of the basal pedicle. In both of them the inner armature of the penis is quite similar as it has an elongated ligule with an apex laterally compressed and curved in the shape of crest, but masaicum has an apex of the aedeagus thicker, straight or at most slightly curved.
Both species have some populations where the sculpture of the elytra has the intervals of the same width and height ("homodyname" sculpture) as well as other populations where on the elytra there are unequal intervals ("eterodiname" sculpture), until you get to specimens with elytra smooth with only large foveae, corresponding to the primary intervals. In fact, the various populations of masaicum and catenatum can be differentiated by means of the examination of male genitalia only.
Starting from west to east, masaicum inhabits both sides of the Rift valley up to the western slope of the Aberdare chain and catenatum is found from the eastern slopes of Mount Aberdare up to Mount Kenya. Jeannel (1940) supposed that the variation of the sculpture of elytra in these species was linked to the succession of the altitudinal belts and to different conditions of humidity of the habitats.
In fact this hypothesis can be verified, for both species.
In case of masaicum , as we do with catenatum, we can distinguish two groups of populations. The ones at the bottom of Rift valley or at relatively lower levels on the slopes of Aberdare chain, having the sculpture of the elytra quite regular (masaicum masaicum) and the other populations, at higher altitudes, on the same mountain and on the opposite side of the Rift valley, that have the sculpture of the elytra variously modified (masaicum jeannelli).
More north, on eastern side of the Rift valley Jeannel (1940) described masaicum cherangani, an enigmatic entity of which only some remains are known.
Further subdivisions, even if already in the literature, are discouraged by the presence of numerous transitional forms.


Calosoma (Carabomorphus) masaicum masaicum Alluaud, 1912

Carabomorphus masaicus Alluaud, 1912: 282 (type: Kijabé 2100m; Muséum National d'Histoire Naturelle, Paris)
Carabomorphus masaicus ssp. Joannae Alluaud, 1912: 283 (type Kijabé, Muséum National d'Histoire Naturelle, Paris)
Carabomorphus catenatus ssp. masaicus Jeannel, 1925: 64
Calosoma (Carabomorphus) brachycerum ssp. masaicum Breuning, 1928: 135
Carabomorphus (Carabomorphus) catenatus masaicus Lapouge, 1932: 396
Carabomorphus masaicus var. alternans Jeannel, 1940: 156 (type Kijabé, Muséum National d'Histoire Naturelle, Paris)

Length 25-30 mm. We consider as masaicum masaicum the populations where the sculpture of the elytra has equal and regular intervals, although in some individuals the tertiary intervals can be reduced (alternans) and in other individuals (joannae) the primary ones can be fragmented into tubercles throughout their length.
Under the scheme of Jeannel, updated with data from Basilewsky (1962), we find masaicum masaicum on the bottom of the Rift Valley, near Nakuru and Naivasha lakes, at 2000m , and on its western slope, in the Kijabé forest, up to 2600m.

Examined specimens
Kenya: Lake Elementaita (EM, SB); Kijabé forest (holotypes of masaicum, joannae, alternans; MNHN)

Notes: Wingless. It adapts to different environments: at the Rift Valley it inhabits savannas and tilled fields and goes up to the lower limit of the forests on the mts Aberdare. Catches are reported in April during the long rain.

Calosoma (Carabomorphus) masaicum masaicum
Alluaud, 1912
Kenya, Kijabé 2100m., février 1912, Alluaud & Jeannel
(holotype) (Muséum National d'Histoire Naturelle, Paris)

Calosoma (Carabomorphus) masaicum masaicum
Alluaud, 1912
Kenya, near lake Elementaita, 15-17.IV.2005,
Werner & Smrz, (coll. Migliaccio)

Calosoma (Carabomorphus) masaicum masaicum
Alluaud, 1912
Kenya, Kijabé 2100m., février 1912, Alluaud & Jeannel
(holotype of Carabomorphus) masaicum var. alternans)
(Muséum National d'Histoire Naturelle, Paris)
Calosoma (Carabomorphus) masaicum masaicum
Alluaud, 1912
Kenya, Kijabé foret 2600m., février 1912, Alluaud & Jeannel
(holotype of Carabomorphus masaicus ssp. Joannae))
(Muséum National d'Histoire Naturelle, Paris)


Calosoma (Carabomorphus) masaicum jeanneli Alluaud, 1912

Carabomorphus masaicus ssp. Jeanneli Alluaud, 1912: 283 (type: Monts Aberdare, de Nyere à Naivasha; Muséum National d'Histoire Naturelle, Paris)
Carabomorphus masaicus ssp. Alluaudi Jeannel, 1912: 279 (type: Monts Aberdare,versant sud-ouest; Muséum National d'Histoire Naturelle, Paris) (preoccupated by Orinodromus Alluaudi Kolbe, 1905)
Calosoma (Carabomorphus) brachycerum ssp. pseudocatenatum Breuning, 1934: 39 (nomen novum pro Alluaudi Jeannel, 1912)
Carabomorphus masaicus ssp. Chappuisi Jeannel, 1940: 156 (type: Mau Escarpment, Molo; British Museum of Natural History, London)

Length 20-25 mm. Here are collected under masaicum jeanneli populations where the sculpture of elytra evolves, from a model where the tertiary intervals disappear or are reduced, the primary ones are fragmented into large tubercles and the secondary ones are modified in continuous ribs, up to types with smooth elytra where only the primary intervals are indicated by large foveae.
These populations inhabit both the western slope of Mt Aberdare as well as the Mau escarpment. On the Aberdare, at 2500 2700m we find a population (pseudocatenatum = alluaudi), with sculpture of elytra still evident, except the tertiary intervals that disappear. At the same altitude on the eastern slope of the Rift valley Jeannel (1940 described a population (chappuisi) very similar in body shape and model of the elytral sculpture, essentially distinguished because of some small differences in the apex of penis. Finally more evoluted population with confused sculpture or, in some specimen, with almost smooth elytra except foveae corresponding to the primary intervals (jeannelli s. str.), is found on the Aberdare, at higher altitudes, above 3000 3200m., in habitat characterized by constantly high humidity.

Examined specimens
Kenya: Aberdare chain (holotypes of jeanneli and of alluaudi, MNHN; paratypes RMCA; SB); Mau Escarpment, Molo (paratypes of chappuisi MNHN, RMCA)

Notes: Wingless. It is found in grassland and alpine meadows at high altitudes. Usually it lives in relatively arid environments, with the exception of the population living in the wet alpine meadow of the mount Kinangop. Catches are reported in January and February just before the long rain.

Calosoma (Carabomorphus) masaicum jeanneli
Alluaud, 1912
British East Africa, Molo 2470m., 19.I.1912, Anderson
(paratype of Carabomorphus masaicus ssp. Chappuisi)
(coll. Musée Royal de l'Afrique Central, Tervuren)


Calosoma (Carabomorphus) masaicum jeanneli
Alluaud, 1912
Kenya, Monts Aberdare versant sud-ouest,
lisière inférieure des forets et prairies découvertes,
2600-1700m, Févr. 1912. Alluaud & Jeannel
(paratype of Carabomorphus masaicus ssp. Alluaudi)
(coll. Musée Royal de l'Afrique Central, Tervuren)
Calosoma (Carabomorphus) masaicum jeanneli
Alluaud, 1912
Kenya: (Afrique or. anglaise), Monts Aberdare, de Nyere a Naivasha, Alluaud & Jeannel; Mt Kinangop vers Est, prairies alpines, 3.000-3.100, Févr. 1912.

Calosoma (Carabomorphus) masaicum jeanneli
Alluaud, 1912
Kenya, Mts Aberdare, de Nyere a Naivasha,3.000-3.100, Févr. 1912, Alluaud & Jeannel
(holotype of Carabomorphus masaicum Subsp. Jeannelli);
(Muséum National d'Histoire Naturelle, Paris)


Calosoma (Carabomorphus) masaicum cherangani Jeannel, 1940

Carabomorphus masaicus ssp. cherangani Jeannel, 1940: 156 (type Kenya, Chip Cherangani; Muséum National d'Histoire Naturelle, Paris)

From the Elgeyo escarpment at 3500, Jeannel (1940) described a population (cherangani), characterized by relatively small dimension and by a short and rounded form of elytra. The tertiary intervals are reduced and the primary ones are fragmented into tubercles throughout their length.
Since only few remains are known, it is difficult to decide on the systematic value of cherangani, which for the moment we keep at the subspecies level .

Examined specimens
Kenya: Elgeyo Escarpment (holotype, MNHN)

Notes: This population is known by some pair of elytra only. No living specimen has been found up to now

Calosoma (Carabomorphus) masaicum cherangani
Jeannel, 1940
Elgeyo escarpment, mont Cherangani 3500m,
19.III.1933, Chappuis & Jeannel
(holotype) (Muséum National d'Histoire Naturelle, Paris)

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