Greek echinos — hedgehog, an allusion to the spiny receptacle scales.
Perennial or rarely annual herbs, spiny. Stems erect or ascending, simple or branching. Leaves along stems, alternate, entire to lobed, spiny. Capitula diskoid, 1-flowered, many grouped together in dense terminal spherical compound heads, surrounded by small bracts. Involucral bracts in 3 or 4 overlapping rows, surrounded by white bristles. Receptacle minute. Florets bisexual, blue, greenish or white. Achenes cylindrical, angled, hairy. Pappus a crown of free or fused scales.
One species has become naturalised in Australia.
Single-flowered capitula in spherical compound heads.
About 120 species from Europe, Africa and Asia.
Source: (2002). Dahlia. In: . Horticultural Flora of South-eastern Australia. Volume 4. Flowering plants. Dicotyledons. Part 3. The identification of garden and cultivated plants. University of New South Wales Press.