Clematis L.
Perennial woody climbers or rarely terrestrial herbs. Lvs cauline, opposite, simple to ternate to 1-2-pinnate; leaflets entire or lobed. Fls ⚥ or unisexual, solitary or in axillary fascicles or simple to compound dichasial cymes; involucre 0 but bracts sometimes connate in pairs. Perianth of 1 petaloid whorl of sepals; sepals 4-6-(8), white, yellow, pink, blue or violet, without nectaries or spurs. Stamens many, spiralled; staminodes present or 0, sometimes petaloid or nectariferous. Carpels with 1 functional ovule. Achenes many, lanceolate to ovate; style elongated and feathery. Receptacle glabrous or hairy.
Key
250 spp., cosmopolitan, mostly temperate. Native spp. 8, naturalised 5.
As pointed out by Godley, E. J. New Zealand J. Bot. 15: 775-776 (1977), the native N.Z. spp. of Clematis have imbricate sepals and are dioecious, whereas most spp. of the genus, including the 5 naturalised in N.Z., have valvate sepals and are ⚥.