''Cycas cairnsiana'' is a species of

cycad Cycads are seed plants that typically have a stout and woody (ligneous) trunk (botany), trunk with a crown (botany), crown of large, hard, stiff, evergreen and (usually) pinnate leaves. The species are dioecious, that is, individual plants o ...

in the genus '' Cycas'', native to northern

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

in northern

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_ ...

on the Newcastle Range. The stems grow to 2–5 m tall and 12–16 cm diameter, with swollen base. The

leaves A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

are dark orange-brown tomentose on emerging, then glaucous blue-green and glabrous with age, 60–110 cm long, bowed, keeled, pinnate, with 180-220 leaflets, the leaflets 8–18 cm long and 2–4 mm wide. The petioles are 18–27 cm long, and armed with sharp spines. The female cones are open, with sporophylls 16–21 cm long, with two to four ovules per sporophyll. The lamina is narrowly triangular, with toothed margins and an apical spine. The

sarcotesta The sarcotesta is a fleshy seedcoat, a type of testa. Examples of seeds with a sarcotesta are pomegranate and some cycad seeds. The sarcotesta of pomegranate seeds consists of epidermal cells derived from the integument, and there are no aril ...

is yellow-brown with a waxy coating, the

sclerotesta This page provides a glossary of plant morphology. Botanists and other biologists who study plant morphology use a number of different terms to classify and identify plant organs and parts that can be observed using no more than a handheld magnify ...

ovoid and flattened. The male cones are solitary, ovoid, 16–20 cm long and 7–10 cm diameter, brown, and with an upturned apical spine. It is named after William Cairns, governor of Queensland from 1875–1877.

Habitat

It grows in dry, rocky, and open woodland terrain on soils derived from granite. Its range is limited to the Newcastle Range of northeast Queensland, with seasonal rainfall of about 1350 mm. This cycad is a close relative of both ''

Cycas couttsiana ''Cycas couttsiana'' is a species of cycad, native to Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name ...

'' and ''

Cycas platyphylla ''Cycas platyphylla'' is a cycad in the genus ''Cycas'', native to Queensland, Australia. The stems are erect or decumbent, growing to 1.5 m tall but most often less than a metre. The leaf, leaves are pinnate, keeled, 60–100 cm long. New ...

''. The plants are remarkable for their intense blue colour, and their resilience to the seasonal extremes of their native range. Its conservation status is near-threatened.

References

Cycad Pages: ''Cycas cairnsiana''
{{Taxonbar, from=Q5197922 cairnsiana Cycadophyta of Australia Endemic flora of Australia Flora of Queensland Near threatened flora of Australia Nature Conservation Act vulnerable biota Vulnerable flora of Australia Near threatened biota of Queensland Taxa named by Ferdinand von Mueller