Namibiotrupes Krikken, 1977

Gussmann S. M. & Scholtz, C. H., 2000, Systematic revision of endemic southern African genera of Bolboceratinae (Coleoptera: Scarabaeoidea: Bolboceratidae), Journal of Natural History 34, pp. 1045-1123 : 1060-1061

Namibiotrupes Krikken

(®gures 4a±g, 5a±h, 6a±f, 7, 8)

Namibiotrupes Krikken, 1977a: 165 ; 1984: 31.

Type species: Namibiotrupes penrithae Krikken, 1977a , by original designation. Bolboceratellus Krikken, 1984: 32 . Syn. nov.

Type species: Bolboceras auspicatum PeÂringuey, 1901 , by original designation.

Description

Body length. 5.6±13.5 mm.

Colour. Light to dark brown but forebody darker.

Head. Dorsal surface asetose. Outer margin of mandible rounded (e.g. ®gure 5b). Labrum declivous in anterior third, with or without feebly elevated transverse carina in anterior third; asetose; anterior margin straight or feebly sinuate. Clypeus, frons with variable ornamentation (®gure 5b, d, f). Antennal club variable in size and shape but basal segment always setose over entire surface.

Pronotum. With steep anterior declivity, topped by straight or bi-angulate transverse ridge adjacent to antero-lateral concavities; lateral margin entire.

Scutellum. Elongate, basal width 1.13±1.27Ölength; deltoid, variabl y punctate.

Elytron. Anterior margin not upturned; striae moderately to strongly impressed, their punctures large and separated by two to less than one puncture diameters; intervals more or less ¯at, with variable punctation; sutural stria terminating at scutellum in a straight line, second stria reaching or almost reaching elytral base.

Prosternum behind procoxae (®gure 4b). With median longitudinal carina.

Metasternum (®gure 4a). Pyriform, bulbous; process with longitudinal, median suture terminating well before anterior declivity, widely separating mesocoxae; process roundedly declivous anteriad; meso-metasternal suture present, positioned halfway down the anterior declivity.

Legs. Protibia of normal shape, non-dilated, ®ve- to eight-dentate. Protibial spur subparallel, with rounded tip, shorter than ®fth tarsomere. Protarsus with ®rst tarsomere shorter than ®fth tarsomere, shorter than tarsomeres 2, 3 and 4 together. Metafemur with punctation and setation of ventral side as in ®gure 4c. Metatibia in lateral view variably shaped (see species descriptions) but always with subapical carina unlobed and with knoblike projections randomly spread over surface above subapical carina. Metatarsus with few subapical setae on tarsomeres 2±4.

Underside. With moderately dense and long setation.

Male genitalia (®gure 4d±g). Aedeagus small, simple in structure, parallel-sided, with lobed parameres.

Distribution (®gure 7). Southern Africa.

Comments. Krikken (1977a, 1984) erected both genera, Namibiotrupes and Bolboceratellus , and maintained that obvious similarities between the two genera might be due to parallelism and plesiomorphism. We argue, however, that the identical and unique shape of the metasternum, the identical shape of the posterior end of the prosternum, the entirely setose surface of the basal segment of the antennal club, the strong similarities in pronotal ornamentation, the large and densely spaced strial punctures of the elytron, the subparallel and short protibial spur, and lastly and importantly the identical shape and structure of the aedeagi of all three species in both genera indicate true relationship and not convergent similarity. We therefore have synonymized Bolboceratellus with Namibiotrupes .