Intertaxon relationships
Stenopterapion meliloti (W. Kirby, 1808)
Tychius crassirostris Kirsch, 1871
Tychius meliloti Stephens, 1831
Tychius squamulatus Gyllenhal, 1835 
consumer (larval stage only)
Hypera melancholica (Fabricius, 1792)
Hypera miles (Paykull, 1792)
Hypera postica (Gyllenhal, 1813)