---

Fore legs usually held with femora vertical, fore basitarsus at least nearly as long as and usually distinctly longer than fore tibia, with short to long dorsal eye extension, vein M ending beyond wingtip in common species, crossvein m-cu absent and those veins well separated, usually warm weather species and usually aquatic, wings usually unmarked but occasionally with poorly-defined bands or spots (see Polypedilum and Demeijerea), often large: Chironominae

Fore legs with fore basitarsus not much longer than and usually much shorter than tibia, eye extension usually short to absent, vein M ending not ending far behind wingtip, crossvein m-cu absent and those veins well separated, tarsomere 4 rarely enlarged (exceptions in Cardiocladius and littoral or marine species), usually cool weather species and often terrestrial, wings unmarked at least in European species, rarely large: Orthocladiinae

Like Orthocladiinae but veins M and Cu close together joined by a crossvein, vein R-M long and not perpendicular to wing axis, tarsomere 4 of common species short and enlarged, female antenna usually with more flagellomeres than previous families, usually cold weather species, wings unmarked: Diamesinae

Fore basitarsus shorter than tibia, female antenna with more than 10 flagellomeres, male with penultimate flagellomere longest (last flagellomere longest in other subfamilies except when male has female-like antennae), crossvein m-cu present, crossvein r-m usually shorter than in Diamesinae, wing usually hairy at least distally, vein R2+3 usually forked (often hard to see), usually with dorsal eye extension, tarsomere 4 rarely enlarged (one exception in Europe), wings often marked at least by dense hairs forming apparent dark patches, warm weather species, small to large: Tanypodinae