Key to Species of Bembecinus rhopalocerus Group

♀♀ Unknown and not included: Bembecinus namaquensis

1a. Forefemur conspicuously expanded basoventrally, its dorsal margin almost straight (Fig. 20b); clypeus near base roundly angulate in profile (Fig. 20a)........ rhopalocerus (Handlirsch)

1b. Forefemur not expanded, somewhat expanded basoventrally in damarensis, in which dorsal margin is shallowly concave basally and clypeus is evenly arcuate in profile........... 2

2a. Labrum with large punctures (Fig. 12a), larger than those on scutum, averaging about one diameter apart................................. karasanus F. Gess and Pulawski, sp. nov.

2b. Labrum with punctures smaller than or equal to those on scutum, averaging several diameters apart..................................................................... 3

3a. Scutum with pair of admedian yellow stripes extending through most of scutum length, and gaster yellow and black; interocellar area yellow (partly so in some gilvus)............. 4

3b. Scutum all black mesally or, if with yellow admedian stripes ( omaruru, many mutabilis, some gariepensis), then gaster ferruginous (at least with ferruginous apical fasciae on terga), with or without yellow apical fasciae on terga; interocellar area black or with minute yellow spot between midocellus and hindocellus in some mutabilis ............................. 7

4a. Terga II-V each with pair of submedian black stripes (Fig. 22) that extend beyond tergal midlength or with pair of black spots near tergal middle.............. somalicus (Arnold)

4b. Terga II-V with narrow black fascia basally or with single median black stripe that extends beyond tergal midlength..................................................... 5

5a. Scape with erect setae along its entire length (except basally).. namibius Pulawski, sp. nov.

5b. Scape without erect setae or with erect setae at apex only........................... 6

6a. Labrum microscopically reticulate between punctures; forebasitarsus barely broadened (Fig. 8a); lower metapleuron closely, microscopically punctate; length 6.0–10.0 mm........................................................................ gilvus R. Bohart

6b. Labrum unsculptured between punctures, at least along midline; forebasitarsus broadened (Fig. 18a); lower metapleuron microscopically areolate; length 9.5–14.0 mm....................................................................... quadristrigatus (Arnold)

7a. Tergum II laterally with erect setae (Fig. 10b), longest setae about 0.5 × midocellar width. 8

7b. Tergum II without erect setae or setae markedly shorter............................ 10

8a. Gastral terga ferruginous, without apical yellow fasciae.............. hyperocrus (Arnold)

8b. Gastral terga with pale yellow apical fasciae (fasciae ill-defined in omaruru with golden tan gaster).................................................................... 9

9a. Clypeus all yellow, practically not angulate near base; minimum interocular distance equal to 2.2 × that between antennal scrobe and base of clypeus....... omaruru Pulawski, sp. nov.

9b. Clypeus black basally, roundly angulate near base in profile (Fig.11a); minimum interocular distance equal to 3.2 × that between antennal scrobe and base of clypeus................................................................ inexspectatus Pulawski, sp. nov.

10a. Terga all ferruginous or with apical ferruginous fasciae (apical terga may be all or partly black), in some species with yellow apical fasciae................................ 11

10b. Terga black and yellow..................................................... 14

11a. Terga largely ferruginous or with ferruginous, apical fasciae, but without yellow apical fasciae...................................................... mutabilis (Arnold)

11b. Terga with yellow apical fasciae............................................. 12

12a. Hindtibial arolium about as long as 0.5 × inner claw; mid- and hindtarsal claws slightly curving inwards at base................................... helicicola Pulawski, sp. nov.

12b. Hindtibial arolium about as long as 0.25 × inner claw; mid- and hindtarsal claws straight (indistinguishable morphologically, but can be determined by association with topotypical males)................................................................... 13

13a. Southern Namibia, Eastern and Western Cape Provinces of South Africa ...................................................................... rhopaloceroides (Arnold)

13b. Southern Namibia, northwestern part of Northern Cape Province of South Africa ................................................ gariepensis F. Gess and Pulawski, sp. nov.

14a. Dorsal surface of tergum I yellow except for median, black, nearly rectangular marking (Fig. 6b) that does not attain posterior margin; scape without erect setae; dorsal margin of forefemur somewhat concave basally, ventral margin slightly expanded basally (Fig. 6a)............................................... damarensis F. Gess and Pulawski, sp. nov.

14b. Tergum I black except for narrow, yellow apical fascia; scape apically with several erect setae (setal length at least 0.5 × midocellar width); dorsal margin of forefemur practically straight, ventral margin not expanded basally........................................... 15

15a. Clypeus all or partly black, mesopleuron black.................... pakhuisae R. Bohart

15b. Clypeus all yellow, mesopleuron partly yellow..................... zebratus R. Bohart

♂♂ Unknown and not included: Bembecinus helicicola

1a. Punctures of labrum larger than those of scutum (Fig. 12a).................................................................... karasanus F. Gess and Pulawski, sp. nov.

1b. Punctures of labrum smaller than or equal to those on scutum........................ 2

2a. Foretibia incrassate in profile (Figs 7b, 19c)...................................... 3

2b. Foretibia not incrassate....................................................... 4

3a. Foretibial inner surface with oblique impression that is visible in dorsal view as an emargination at tibia’s basal third (Fig. 19b).......................... rhopaloceroides (Arnold)

3b. Foretibia with inner surface flat or nearly so, without emargination in dorsal view (Figs 7a and b).................................. gariepensis F. Gess and Pulawski, sp. nov.

4a. Tergum II with erect setae (Fig. 10c), at least laterally; longest setae about 0.5 × midocellar width..................................................................... 5

4b. Tergum II without erect setae or setae markedly shorter............................. 7

5a. Clypeus, supraclypeal area, and stripes along orbit pale yellow........................................................................ inexspectatus Pulawski, sp. nov.

5b. Clypeus, supraclypeal area, and frons all black.................................... 6

6a. Gastral terga without pale yellow apical fasciae; tergum VII shorter, rounded (Fig. 10d).............................................................. hyperocrus (Arnold)

6b. Gastral terga with pale yellow apical fasciae (fasciae ill defined in specimens with golden tan gaster); tergum VII longer, roundly triangular (Fig. 16)....... omaruru Pulawski, sp. nov.

7a. Apical flagellomere curved, excavated posteriorly, only slightly so in pakhuisae (Fig. 17b). 8

7b. Apical flagellomere not curved, not excavated posteriorly or insignificantly excavated.... 11

8a. Gastral terga largely ferruginous (tergum I black basally, following terga all ferruginous or narrowly black basally)........................................... mutabilis (Arnold)

8b. Gastral terga yellow and black................................................. 9

9a. Tergum VII longer, roundly triangular (Fig. 6d); apical flagellomere markedly curved and excavated (Fig. 6c)........................... damarensis F. Gess and Pulawski, sp. nov.

9b. Tergum VII shorter, roundly trapezoid (Fig. 17c); apical flagellomere slightly curved and excavated (Fig. 17b)........................................................... 10

10a. Apical flagellomere less curved (Fig. 17b); yellow apical fascia of tergum II slightly shorter to longer than black, basal part, at least mesally................... pakhuisae R. Bohart

10b. Apical flagellomere in most specimens more curved (Fig. 23a); yellow apical fasciae of tergum II shorter than black, basal part.............................. zebratus R. Bohart

11a. Gastral terga largely ferruginous..................... namaquensis Pulawski, sp. nov.

11b. Gastral terga yellow and black (with some ferruginous on tergum I in rhopalocerus).... 12

12a. Terga II-V with pair of submedian black stripes that extend beyond tergal midlength or with pair of black spots near tergal middle (Fig. 22)..................... somalicus (Arnold)

12b. Tergum II-V with narrow black fascia basally or with single median black stripe that extends beyond tergal midlength.................................................... 13

13a. Scape with erect setae along its entire length (except basally). namibius Pulawski, sp. nov.

13b. Scape without erect setae or with erect setae at apex only......................... 14

14a. Distance between clypeus and antennal scrobe equal to about 0.3 × least interocular distance (Fig. 8b); lower gena without erect setae between mandibular base and occipital carina; length 7.0–9. 2 mm .................................................... gilvus R. Bohart

14b. Distance between clypeus and antennal scrobe equal to 0.6–0.7 × least interocular distance; lower gena with erect setae between mandibular base and occipital carina; length 12.1–14. 6 mm ..................................................................... 15

15a. Clypeus roundly angulate basally (best seen in profile, Fig. 20a); tergum VII broadly rounded (Fig. 20c); scutum black mesally........................ rhopalocerus (Handlirsch)

15b. Clypeus evenly arcuate in profile; tergum VII less rounded, more prominent mesally (Fig. 18d); scutum with pair of admedian yellow stripes.............. quadristrigatus (Arnold)