Illustration: Hill 1996, fig. 26. Historical notes: Described in 1918 by surveyor William Vincent Fitzgerald (--) on the basis of collections and observations he made during an expedition to the Kimberley region in 1905. No holotype was designated, but the distribution was cited as "Summits of Mts. Herbert, Broome, and Bold Bluff (W.V.F.)", and this is apparently the only extant Fitzgerald collection of this species. The specimens in both NSW and PERTH include a leaf portion, together with both male and female sporophylls, and so must have been gathered from more than one plant. The leaf section in NSW has been designated the lectotype (Hill 1996). The leaf sections in NSW and PERTH can be matched at the break, and so are from the same leaf. The NSW portion, however, includes part of the petiole and the lower leaflets, which are specifically mentioned in the protologue. This distinctive species has generally been accepted by most authors, although Schuster (1932) had reduced it to a variety of C. media. Distinguishing features: Distinguished by the strongly keeled leaves with angled, broad, often white-tomentose, glaucous leaflets with slightly recurved margins. The leaves are consistently terminated by paired leaflets, and leaflets gradually reduce in size to grade into spines on a short petiole in both C. furfuracea and C. basaltica. Microsporangiate cones are also relatively long and narrow in this species, and somewhat broader in C. basaltica. Sporadic individuals also lack the glaucous leaf wax, leading to the occasional occurrence of green plants in stands of otherwise blue plants (similar occurrences are present in C. pruinosa, which see). Leaves of the western occurrences (on Kimbolton) tend to lose their tomentum as they mature, whereas the tomentum may persist for several years on leaves of the plants in the King Leopold Range. The western occurrences also tend to have broader leaflets than those occurring in the King Leopold Ranges. The ranges of both characters in the two populations overlap substantially, and no clear infraspecific division can be recognised. Distribution and habitat: A sporadic species in the Kimberley region of Western Australia, known mainly from elevated parts of the King Leopold Range, with another occurrence on Kimbolton and on islands to the north of there, such as Heywood Island. Usually on skeletal sandy soils on hard siliceous metasandstone, on steep slopes. The occurrences at Kimbolton are unusual in being both on similar substrates to the above, and also on red clay on rocky basalt outcrops. Conservation status: not threatened.
Description:
Stems arborescent, to 2(-4) m tall, 18-22 cm diam. at narrowest point. Leaves blue, dull, 80-150 cm long, strongly keeled (opposing leaflets inserted at 40-70° on rachis), with 100-220 leaflets, with white tomentum persistent below; rachis consistently terminated by paired leaflets. Petiole 15-26 cm long, pubescent, spinescent for 5-50% of length (often only 2-3 distal spines). Basal leaflets gradually reducing to spines, 1 mm long. Median leaflets simple, weakly discolorous, 70-200 mm long, 6.5-7.5 mm wide, inserted at 40-50° to rachis, decurrent for 3-7 mm, narrowed to 4.5-6 mm at base (to 75-85% of maximum width), 9-13 mm apart on rachis; median leaflets section flat to slightly keeled; margins slightly recurved; apex acute, spinescent; midrib raised above, raised below (prominent). Cataphylls linear, soft, pilose, persistent. Pollen cones narrowly ovoid to fusiform, orange to brown, 30-40 cm long, 7-9 cm diam.; microsporophyll lamina firm, not dorsiventrally thickened, 30-40 mm long, 16-20 mm wide, fertile zone 20-25 mm long, sterile apex 12-18 mm long, deflexed, apical spine prominent, sharply upturned, 6-12 mm long. Megasporophylls 26-36 cm long, white-tomentose to grey-tomentose or brown-tomentose; ovules 4-8, glabrous; lamina lanceolate, 70-95 mm long, 10-22 mm wide, regularly dentate, with 12-20 soft lateral spines 2-5 mm long, 2-3 mm wide, apical spine distinct from lateral spines, 25-65 mm long. Seeds flattened-ovoid, 32-36 mm long, 27-32 mm wide; sarcotesta orange-brown, strongly pruinose, 2-3 mm thick; fibrous layer absent; sclerotesta smooth. Spongy endocarp absent.
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