Deciduous, terrestrial orchids growing in clonal colonies, with dimorphic flowering and non-flowering plants. Non-flowering plants consist solely of a leafy rosette; flowering plants consist of a thin, wiry, leafless stem and an inflorescence, but usually no rosette until later (Arthrochilus longicollis and A. rosulatus are unusual in having a stem-encircling basal rosette). Rosette terminating stem or on basal lateral growth on peduncle. Leaves 2–6 spreading from central point in rosette, mostly ground-hugging, petiolate or sessile. Raceme multiflowered; peduncle thin, wiry, with many sterile bracts. Flowers non-resupinate, dull-coloured, insectiform. Tepals inconspicuous, mostly recurved or reflexed against ovary. Dorsal sepal larger than lateral sepals, recurved. Lateral sepals basally attached to column foot. Petals narrower than sepals. Labellum hinged by short claw to underside of column foot, projecting out like an insectiform lure. Labellum lamina unlobed, simple and vestigial. Callus large, hammer-shaped, dominating labellum, main body covered with colourful hairs and/or shiny, club-shaped calli or warty calli, limb extending from main body ending in an irregularly swollen head-like structure (apex). Column slender, curved in semi-circle, with 2 unequal pairs of long, slender, curved wings (one pair above anther); front hairy, often spotted. Pollinia four, deeply bilobed, mealy, yellow, no viscidium.
These orchids grow in a range of habitats including shrubby forest, heathland, monsoon forest, rocky escarpments and sedgeland in soils ranging from freely draining to low-lying flats and swampy areas that become soaked during the wet season.
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