Key to Haptomerus species
1. Elytra with conspicuous, long, sparse, piliform erect setae..................................... H. natalis Marshall
- Elytra without any erect setae............................................................................ 2
2. Body lacking appressed scales, integument metallic blue; rostrum short, 1.3–1.4 × longer than wide; epifrons between antennal scrobes 0.8–0.9 × as wide as width of rostrum at the same place................................. H. aeneus Hustache
- Body with distinct appressed scales, integument if partly visible brown to black without metallic sheen; rostrum long, 2.2–4.2 × longer than wide; epifrons between antennal scrobes 0.3–0.5 × as wide as width of rostrum at the same place........... 3
3. Funicle segment 2 1.2–1.4 × longer than segment 1; appressed scales on elytra and pronotum unicolorously bright green with metallic sheen......................................................................... H. lepidus (Brullé)
- Funicle segment 1 1.4–1.6 × longer than segment 2; appressed scales on pronotum and elytra grey or brown, if greenish, then form only spots....................................................................................... 4
4. Rostrum in dorsal view distinctly evenly tapered from base to apex; elytra with distinct transverse stripes or longitudinal stripes on intervals 3 and 5.............................................................................. 5
- Rostrum in dorsal view parallel-sided or even slightly enlarged apicad at anterior part; elytra without stripes or with darker longitudinal stripe at intervals 2–4........................................................................... 6
5. Elytra with three conspicuous transverse stripes; disc of pronotum and elytra with long, oval, sparse, dark brownish, appressed scales; funicle segments 1 1.8–1.9 × longer than segment 2; tarsal segments 3 and onychia equally long.................................................................................... H. maculosus Borovec & Nakládal, sp. n.
- Elytra with distinct longitudinal stripe at basal half of interstria 3, interrupted longitudinal stripe on interstria 5 and complete stripe on external interstriae; disc of pronotum and elytra with rounded, dense, pale brownish, appressed scales; funicle segments 1 1.4–1.6 × longer than segment 2; tarsal segments 3 1.5 × longer than onychium........... H. angolanus Marshall
6. Onychium very short, 0.4 × as long as tarsal segment 3; elytra with rounded appressed scales, small brownish and twice bigger greyish............................................................................... H. brevitarsis Voss
- Onychium long, at least 0.8 × as long as tarsal segment 3; elytra with rounded appressed scales of equal size or with differently sized, then oval to long oval............................................................................. 7
7. Apical part of rostrum densely squamose; elytral striae linear, very slender, many times narrower than wide interstriae; appressed scales completely covering integument on pronotum................................. H. limis (Gyllenhal)
- Apical part of rostrum glabrous, shiny; elytral striae distinctly punctured, almost as wide as narrow interstriae; appressed scales sparsely covering pronotum, integument visible........................................................ 8
8. Punctures on elytra form regular striae; elytra with spots of denser appressed scales on short base of intervals 3 and 7 with 8, and small spots at apical third of intervals 3–7 or 5–7...................................... H. mashunus Marshall
- Elytra irregularly punctate, punctures confused, not forming striae; elytra with somewhat denser stripes on intervals 3 and 7..................................................................................... H. confusus Marshall