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Illustration: Gardner 1923, Hill 1996.
Historical notes: Recognised as a distinct species by Western Australian government botanist Charles A. Gardner in 1923 on the basis of collections he made in an expedition to the Kimberley region in 1921. Later authors such as Schuster (1932) and Maconochie (19--) ignored this species or included it in a broad concept of C. media.
Distinguishing features: Distinguished by the glossy green new growth and the discolorous leaflets with midrib equally prominent above and below. The leaves are very similar to those of C. armstrongii, but the plant is more robust in all respects. Cataphylls are coated with a thick wool similar to that present in C. canalis and C. lanata, but not seen in C. armstrongii.
Distribution and habitat: Known from several scattered populations in the north-west of the Kimberley region of Western Australia, mostly on sandy soils in savanna forest with Eucalyptus miniata, E. tetrodonta or Corymbia latifolia. Intergradational populations with C. basaltica are known.
Conservation status: Not considered to be at risk.
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Stems arborescent, to 5(-8) m tall, 12-15 cm diam. at narrowest point.
Leaves bright green or blue (when new, aging to bright glossy green), semiglossy, 60-110 cm long, slightly keeled to flat (not keeled) in section (opposing leaflets inserted at 130-180° on rachis), with 90-170 leaflets, with white and orange tomentum shedding as leaf expands; rachis usually terminated by a spine. Petiole 18-40 cm long, glabrous, unarmed (or with few distal spines). Basal leaflets not gradually reducing to spines.
Median leaflets simple, weakly discolorous, 60-170 mm long, 4.5-8.5 mm wide, inserted at 45-60° to rachis, decurrent for 3-5 mm, narrowed to 2.5-4 mm at base (to 40-70% of maximum width), 4-12 mm apart on rachis; median leaflets section flat; margins flat; apex aristate, not spinescent; midrib raised above, raised below.
Cataphylls linear, pungent, densely floccose, 60-100 mm long, persistent.
Pollen cones ovoid, orange, 10-14 cm long, 9-11 cm diam.; microsporophyll lamina firm, not dorsiventrally thickened, 25-35 mm long, 14-16 mm wide, fertile zone 22-26 mm long, sterile apex 5-10 mm long, level, apical spine prominent, sharply upturned, 8-11 mm long.
Megasporophylls 16-22 cm long, grey-tomentose and brown-tomentose; ovules 2-4, glabrous; lamina lanceolate, 40-65 mm long, 17-28 mm wide, regularly dentate, with 12-30 pungent lateral spines 1-5 mm long, 1-2 mm wide, apical spine distinct from lateral spines, 15-20 mm long.
Seeds flattened-ovoid, 38-45 mm long, 36-40 mm wide; sarcotesta orange-brown, not pruinose, 3-4 mm thick; fibrous layer absent; sclerotesta smooth. Spongy endocarp absent.
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