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Cycas cairnsiana

Dry, rocky, and open woodland terrain on soils derived from granite.·Arborescent·Near-threatened

Cycas cairnsiana is a species of cycad found in northern Queensland, Australia, specifically on the Newcastle Range. It is characterized by its distinctive blue-green leaves, spiny petioles, and a stem that can reach up to 5 meters in height with a swollen base. This species thrives in dry, rocky woodlands and is noted for its resilience to seasonal extremes.

Key Facts

  • Native to the Newcastle Range in northern Queensland, Australia.
  • Stems can grow 2-5 meters tall with a swollen base.
  • Leaves are glaucous blue-green, pinnate, with numerous narrow leaflets.
  • Petioles are armed with sharp spines.
  • Conservation status is near-threatened.
  • Named after William Cairns, former governor of Queensland.
Cycas cairnsiana
Scientific Name
Cycas cairnsiana
Family
Cycadaceae
Native Range

Northern Australia, Northern Queensland

Stem Characteristics

2–5 m Tall, 12–16 cm Diameter, Swollen Base

Leaf Characteristics

60–110 cm Long, Glaucous Blue-Green and Glabrous With Age, Bowed, Keeled, Pinnate, 180-220 Leaflets, Leaflets 8–18 cm Long and 2–4 mm Wide, Petioles 18–27 cm Long, Petioles Armed With Sharp Spines

Cone Characteristics
  • Female cones are open with sporophylls 16–21 cm long, bearing two to four ovules per sporophyll.
  • Lamina is narrowly triangular with toothed margins and an apical spine.
  • Sarcotesta is yellow-brown with a waxy coating.
  • Male cones are solitary, ovoid, 16–20 cm long and 7–10 cm diameter, brown, with an upturned apical spine.
Average Height
2–5 m
Leaf Arrangement
Pinnate
Seed Characteristics
  • Sarcotesta is yellow-brown with a waxy coating.
  • Sclerotesta is ovoid and flattened.
Etymology
Named after William Cairns, governor of Queensland from 1875–1877.

About Cycas cairnsiana

Cycas cairnsiana is a species of cycad native to a specific region in northern Australia. It is primarily found on the Newcastle Range in northern Queensland, thriving in dry, rocky, and open woodland environments, typically on soils derived from granite. This species is notable for its resilience to the seasonal extremes characteristic of its native habitat and for the striking blue-green color of its mature foliage.

Botanical Characteristics

The stems of Cycas cairnsiana can reach heights of 2 to 5 meters and have a diameter of 12 to 16 cm, often featuring a swollen base. Its leaves are pinnate, measuring between 60 and 110 cm in length. Young leaves emerge with a dark orange-brown tomentose covering, which gives way to a glaucous blue-green and glabrous appearance as they mature. Each leaf is composed of 180 to 220 leaflets, which are typically 8 to 18 cm long and 2 to 4 mm wide. The petioles, measuring 18 to 27 cm, are armed with sharp spines. Reproductive structures include female cones with sporophylls up to 21 cm long, and male cones that are ovoid, 16 to 20 cm long, and 7 to 10 cm in diameter.

Naming and Conservation

The species is named in honor of William Cairns, who served as the governor of Queensland from 1875 to 1877. Cycas cairnsiana's conservation status is currently assessed as near-threatened, indicating a need for continued monitoring and conservation efforts to ensure its survival in its limited natural range. It shares close relationships with other cycad species such as Cycas couttsiana and Cycas platyphylla.

Source: Wikipedia ↗

Frequently Asked Questions

What is the scientific name for this cycad species?

The scientific name for this cycad species is Cycas cairnsiana.

Where is Cycas cairnsiana found naturally?

Cycas cairnsiana is native to northern Australia, specifically in northern Queensland on the Newcastle Range.

What are the typical characteristics of its leaves?

The leaves of Cycas cairnsiana are typically 60-110 cm long, glaucous blue-green, and pinnate, featuring 180-220 leaflets. Each leaflet is 8-18 cm long and 2-4 mm wide, and the petioles are spiny.

What is the habitat of Cycas cairnsiana?

This cycad species grows in dry, rocky, and open woodland terrain, often on soils derived from granite. It is found in an area with seasonal rainfall of about 1350 mm.

What is the conservation status of Cycas cairnsiana?

The conservation status of Cycas cairnsiana is classified as near-threatened.

How tall do Cycas cairnsiana plants grow?

The stems of Cycas cairnsiana can grow to be 2 to 5 meters tall and have a diameter of 12 to 16 cm, often featuring a swollen base.