Bolbaoeer namibiensis, Gussmann & Scholtz, 2001

Gussmann, S. M. V. & Scholtz, C. H., 2001, Systematic revision of the Afrotropical genus BolbaOEer Vulcano, Martinez and Pereira (Coleoptera: Scarabaeoidea: Bolboceratidae: Bolboceratinae), with descriptions of eight new species, Journal of Natural History 35 (7), pp. 1013-1084 : 1077-1079

BolbaOEer namibiensis sp. nov.

(®gures 4r±t, 23i±p, 25)

Description male

Body length 20.8±23.8 mm (5 specimens). Colour light brown to dark brown, head and pronotum usually slightly darker. Outer margin mandible very feebly sinuate. Clypeus with bituberculate, straight to feebly arcuate transverse posterior carina; tubercles in line with clypeo-frontal transition; posterior carina more or less as long as anterior carina, sometimes obsolete between tubercles. Frons very feebly depressed posterior to posterior clypeal carina. Antennal club with glabrous area of basal segment about one-third of exposed surface. Pronotum with anterior margin medially raised and bituberculate / bihorned (®gure 4r, s), in major males in dorsal view slightly projecting over frons; with pair of long, slightly inward curved, outer horns along posterior margin in major males (®gure 4r) or with pair of short, more approximated horns in minor males (®gure 4s) and with transverse swollen noncarinate areas in between (as B. sasakii , see ®gure 6a); disc with ®ne, well-spaced punctures, these increasingly interspersed by large, often conūent punctures towards sides and along anterior margin of pronotum. Scutellum with surface coarsely punctate. Elytron with strial punctures separated by four to six puncture diameters; intervals with approximately ®ve to six punctures between two striae. Protibia ®veto six-dentate. Protibial spur more or less as long as ®fth tarsomere, acuminate. Metatrochanter of unmodi®ed shape; entire surface with dense, moderately long setation. Metafemur in ventral view in posterior third with line of densely spaced, moderately long and long setae; with dense, moderately long and long setae in basal area and basal third along posterior margin; with fairly dense, long setae in anterior third and apical area; remaining areas with sparse, long setation. Metatibia in lateral view with subapical carina bilobed; with unmodi®ed spurs. Underside with sternites 4, 5 and 6 strongly modi®ed (®gure 23h±k); processes on sternite 4 and 5 gradually narrowing from broad base to rounded apex (®gure 23k); apex of pygidium sharply incised (®gure 23h); median incision dividing apical ®fth of pygidium; the two halves of pygidium in basal four ®fth fused to a clearly visible suture (stippled lines in ®gure 23h). Genitalia with aedeagus as in ®gure 23l±n; genital capsule apically with moderately long setation.

Description female

Body length 20.8±23.1 mm (6 specimens). Colour as in male. Outer margin of mandible rounded. Frons with strongly raised bituberculate, transverse carina; position of carina variable, from between eye-canthi to slightly anterior to posterolateral genal angle; carina straight and slightly shorter than anterior clypeal carina. Antennal club as in male. Pronotum with anterior margin medially raised, in frontal view slightly bisinuate (as in ®gure 4t), in dorsal view feebly arcuate; with transverse distinctly carinate swelling at median portion of disc; carina in frontal view as in ®gure 4t, in dorsal view feebly bisinuate; area anterior to carina (shaded area in ®gure 4t) with very densely spaced small, deep punctures; on feebly swollen areas lateral to densely punctate area and also along posterior margin with densely spaced large punctures; otherwise with very densely spaced, partially conūent, large punctures. Scutellum and elytron as in male. Protibia and protibial spur as in male. Metatrochanter of unmodi®ed shape; with dense, moderately long setation in basal third and along posterior margin; remaining surface asetose. Metafemur in ventral view in posterior third with line of fairly dense, moderately long and long setae; with fairly dense and long setae in anterior third and apical area; with fairly dense, moderately long setae along posterior margin; remaining areas with few isolated setae. Metatibia as in male. Underside with sternite 5 postero-medially feebly but discernibly swollen (not illustrated); apex of sternite 6 feebly arcuately emarginate (®gure 23p) or narrowly truncate; apex of pygidium sharply triangularly incised (®gure 23o); median incision dividing approximatel y apical seventh of pygidium; the two halves of pygidium in basal six seventh fused to a clearly visible suture (stippled lines in ®gure 23o).

Distribution (®gure 25). Northeastern parts of Namibia, northern parts of Botswana (`Ngamiland’) and southern Zambia.

Type material examined. HOLOTYPE l[diss.]:`[ Namibia], Abachaus [19.47S 16.44E], iii.53, G. Hobohm’ /` Bolboceras princeps , det. G. Frey 1960’ (TMSA); ALLOTYPE m: same data (TMSA); 5 PARATYPES: 1 l[diss.],`S.W. Protect., Narugas [misprint, Nuragas 19.16S 18.52E], Jan. 1919, R. Lightfoot’ /`’ /` princeps Kolbe ?’ [handwritten by Andreae, ex curator at SAMC] (SAMC); 1, same data but:`Nuragas’,`m’ (SAMC); 1,` Namibia, Caprivi Nakatwa, Kwando River, 18.10S 23.25E, 950m, 09.iii.1992, R. Oberprieler’ (SANC); 1 l[diss. 18.v.1994 by Riaan Stals but no aedeagus found],`S. Africa: Bechuanaland. Ngamiland. Nov.1930 ± Jan.1931, G.D. Hale Carpenter, B.M. 1931-160.’ (BMNH); 1 l[diss.],`S.W. Protectorate’ /`’ l /` princeps Kolbe ?’ [handwritten by Andreae, ex curator SAMC] (SAMC).

Additional material examined (4 specimens). Namibia: 1,`D.S.W. Afrika, Dr. Liesegang S.G. ’ /`BolbaOEer` ( ZMHB); 1m,`Deutsch S.W.Afrika, Rietfontein [ambiguous but probably`Fort Rietfontein’ at 21.52S 20.53E and not Dabegabis at 28.15S 18.34E], iii.97, Borchmann S. ’ /`Rietfontei n d. 5.3.97 (am Abend bei Licht) [ill.] K.Borchmann’ [handwritten] /`copridoide s Kolbe *’ [handwritten on green label by unknown curator] /`Type’ [printed on red label] /`70732 ’ ( ZMHB); 1,`Grootfontein [19.35S 18.07E], S.W. Protect. ’ /`m’/`princep s Kolbe?’ [handwritten by Andreae, ex curator SAMC] ( SAMC) ; Zambia: 1m,` Zambia , 1023m, 50km NW Kasangula, 17.28S ± 24.56E, 7.4.1997, WD Haacke, E.Erb’ ( TMSA) .

Etymology. Named after the country where most of the type material was collected.

Comments. Two of the male specimens of B. namibiensis have previously been confused with B. princeps although the strong modi®cations on sternites 4 to 6 and on the pygidium in male B. namibiensis bear no similarity to the comparatively feeble modi®cations in male B. princeps . At most the dorsal aspects of males of both species show some super®cial resemblance although the pronotal punctation diOEers signi®cantly between the two species (compare descriptions). The modi®cations on sternites 4, 5 and 6 place B. namibiensis in the B. abyssinicus species-group. This is supported by the females of B. namibiensis which have the typical pronotal punctation that is found in most females of the B. abyssinicus species-group. The above male / female association is certain as two combinations, consisting of a male and female each, were collected at two diOEerent localities. We did, however, decide to include only the females from these combinations into the type series while listing the remaining single females as additional material.

Illustrations of the pronotal armature (®gure 4r, s), the sternal and pygidial modi®cations (®gure 23h±k) and illustrations of the aedeagus (®gure 23l±n) for males of B. namibiensis do not need any further explanation as they clearly show the diOEerences to males of other members of the B. abyssinicus species-group. At most, males of B. namibiensis could be confused with males of B. sasakii . Their dorsal aspects, in particular with respect to the pronotal armature, are virtually identical. The sternal and pygidial modi®cations and the genitalia, however, diOEer between males of the two species (compare ®gure 23h±n with 22i±k). The holotype of B. namibiensis represents a major male. Females of B. namibiensis are best identi®ed by the following modi®cations: apex of sternite 6 feebly arcuately emarginated or narrowly truncate and apex of pygidium with sharp triangular incision. DiOEerences between females of B. namibiensis and the very similar females of B. mozambiquensis are already explained under the former.

The distribution of B. namibiensis , based on a small number of specimens, extends from northern Namibia westwards into northern Botswana and southern Zambia. Thus B. namibiensis is sympatric only with populations of the widely distributed B. princeps .