The genus Alphitobius Stephens (Coleoptera, Tenebrionidae, Alphitobiini) in Africa and adjacent islands

Abstract All species of the genus Alphitobius Stephens, 1829 (Alphitobiini Reitter, 1917, subfamily Tenebrioninae Latreille, 1802) from Africa and adjacent islands are revised. New species: Alphitobius capitaneus sp. n. from Kenya. New synonyms: Cryptops ulomoides Solier, 1851, syn. n. of Alphitobius diaperinus (Panzer, 1796); Alphitobius rufus Ardoin, 1976, syn. n. of Alphitobius hobohmi Koch, 1953); Peltoides (Micropeltoides) crypticoides Pic, 1916, syn. n. of Peltoides (Micropeltoides) opacus (Gerstaecker, 1871), comb. n. Homonym: Alphitobius ulomoides Koch, 1953 = Alphitobius arnoldi nom. n. New combinations from Alphitobius: Ulomoides basilewskyi (Ardoin, 1969), comb. n.; Peltoides (Micropeltoides) opacus (Gerstaecker, 1871), comb. n. Figures of all examined species are added and a species key is compiled.


Introduction
Two species of the genus Alphitobius Stephens, 1829(Alphitobiini Reitter, 1917, subfamily Tenebrioninae Latreille, 1802, namely A. diaperinus (Panzer, 1796) and A. laevigatus (Fabricius, 1781), have a cosmopolitan synanthropic distribution. All the other species were described from mature habitats in Africa south of the Sahara, so probably this is also the native area of both synanthropic species. Gebien (1921) presented the first key of the African species, including species of the genus Diaclina Jacquelin du Val, 1861. Additional species were added by Koch (1953), Ardoin (1958Ardoin ( , 1963aArdoin ( , 1969Ardoin ( , 1976, Ferrer (1983), and Bremer (1985). The goal of the present paper is a taxonomic revision of the African species, including the description of a new species, the recognition of new synonymies, a new name for a homonym, the transfer of two species from Alphitobius to Ulomoides and Peltoides respectively, providing also figures of all examined species, and compiling of a species key as well. Unfortunately, two taxa (A. grandis Fairmaire, 1897 andA. limbalis Fairmaire, 1901) from Madagascar remained unknown to the authors.
The separation of Alphitobius from Diaclina was doubtful for a long time. Gebien (1921) separated both by the width of the genal canthus (wider than eyes in Alphitobius, narrower or as wide as eyes in Diaclina). However, some taxa described under Alphitobius have the canthus not broader than eyes (for example A. lamottei Ardoin, 1963, see also in species key of Bremer and Girard 1996). Only recently, Matthews and Bouchard (2008) defined the Alphitobiini, separated this tribe from the Diaperini, and discussed also a few differences between Alphitobius and Diaclina.

Etymology.
The new name is derived in honor of George Arnold , former curator in the "Rhodesia Museum" (now Natural History Museum of Zimbabwe, Bulawayo), specialist of African Hymenoptera, and collector of the holotype.
Distribution. Zimbabwe, Congo (Koch 1953); Somalia, Kenya, Tanzania (new records).  Diagnosis. Alphitobius capitaneus sp. n. is distinguished from its congeners by size and shape of body. A similar body shape, especially the shape of pronotum has A. lamottei Ardoin, 1963, but this species is smaller (body length ≤ 7.0 mm) and differs by the reddish colour, by much finer punctation of dorsal surface, by longer and less distinct serrate antennae with basal antennomeres more elongated, and by the somewhat more stretched and apically narrowed apicale of aedeagus.
Description. Body length 8.8 mm, width at widest point behind middle of elytra 3.6 mm. Elongate, blackish brown, matt; borders of pronotum, lateral borders of elytra, sutural interval, and scutellum paler reddish brown. Complete dorsal surface with very fine and dense punctation, punctures bearing a minute seta. Head sub-trapezoidal; outline continuous, not interrupted between clypeus and frons; apical margin of epistome shallowly emarginate in the middle; fronto-clypeal suture complete and linearly impressed. Eyes large, constricted by genal canthus, dorsal part smaller than ventral part. Genal canthus hardly projecting beyond contours of eyes, with the outlines nearly continuous with the outlines of the latter. Tempora strongly narrowed towards neck. Antennae thickened, not reaching the base of pronotum, with the seven distal antennomeres forming a kind of club; 2 nd antennomere wider than long; 3 rd elongate, one and a half times as long as wide; 4 th only slightly, 5 th to 10 th distinctly wider than long and distinctly serrate; distal antennomere rounded, as wide as long. Pronotum transverse, width/length ratio 1.7; transverse convex, widest at base, shallowly arcuate narrowing to apex. Anterior margin shallowly emarginate, basal margin bisinuate, all margins finely bordered; lateral margins separated from discal convexity by a narrow submarginal depression. Anterior and posterior corners rectangular. Propleura densely covered with small seta bearing tubercles, only along outer margins nearly smooth. Prosternum rugosely punctured, prosternal apophysis bent down behind procoxae. Elytra convex, elongate oval with subparallel sides and densely punctured striae; scutellar striole absent; intervals much broader than striae, nearly flat on disc, becoming more and more convex laterally and distally; lateral margins in dorsal view visible nearly over entire length, only concealed around apex; base as wide as base of pronotum; humeral angles obtuse, distinct. Scutellum large, triangular. Mesoventrite roughly punctured, with shiny median carina in basal part; triangular apophysis raised upwards and excavate. Metaventrite shiny, with fine median sulcus, finely punctured on disc, somewhat more coarsely punctured laterally. Abdominal ventrites with very dense and fine punctation throughout, basally and laterally longitudinally wrinkled. Tibiae gradually and faintly dilated towards apex, without modifications. Aedeagus as in Fig. 20.

Remarks.
It seems doubtful to the authors, if the above listed female (body length 6 mm) without any data is really a type specimen. Other material of this taxon is unknown to the authors. The species is said to be similar to A. luctuosus (synonym of Alphitobius crenatus (Klug, 1833) (Fairmaire 1901), but is characterised by larger body size (6 mm), rounder pronotum and larger punctures in elytral striae.

Alphitobius niger
Remarks. Unfortunately, this species was overlooked during the study, and was added here only during the review process. The species is said to be similar to A. ulomoides, for diagnosis and figures see Ferrer (1983). Genal canthus projecting outwards beyond contours of eyes, pronotum widest near base, aedeagus with acute apicale, body length 8 mm.
Type locality. "Lake Manyara". Distribution. Tanzania (type locality). Type locality. "Lulua, Tshibamba". Remarks. Bremer (1985) already assumed, that some specimens of the type series of A. leleupi and A. parallelipennis in TMSA are mislabelled, and that the actual depository of the holotype of A. parallelipennis seems unknown, at least it is not present in MRAC as published in the original description. De Meyer (VII.2013 in an email to the senior author) confirmed, that the holotype is lacking in MRAC with the remark "non renvoyé par Koch". During the last visit of the senior author in TMSA, the mixture of locality and type labels could be confirmed, and also corrected. The holotype of A. parallelipennis could be recognised without any doubts among the type series of A. leleupi, although mislabelled, and was transferred with correct secondary labels from TMSA to MRAC.

Peltoides
Remarks. The examination of the type of Alphitobius opacus Gerstaecker, 1871 shows, that the original assignment to Alphitobius is wrong and that this species must be transferred to the genus Peltoides Laporte, 1832, subgenus Micropeltoides Pic, 1916, because of entirely different body shape, different shape of antennomeres, and different shape of male genitalia with the base of basale not asymmetrical as in Alphitobiini. The type of Peltoides (Micropeltoides) crypticoides Pic, 1916 fully coincide with opacus, and is thus a junior synonym.