Species profile—Cycas platyphylla

Classification

Plantae (plants) → Equisetopsida (land plants) → Cycadaceae → Cycas platyphylla

Photo of Cycas platyphylla () - Forster, P.,Queensland Herbarium, DES (Licence: CC BY NC)

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Species details

Kingdom: Plantae (plants)
Class: Equisetopsida (land plants)
Family: Cycadaceae
Scientific name: Cycas platyphylla K.D.Hill
WildNet taxon ID: 8897
Nature Conservation Act 1992 (NCA) status: Vulnerable
Environment Protection and Biodiversity Conservation Act 1999 (EPBC) status: Vulnerable
Conservation significant: Yes
Confidential: Yes
Endemicity: Native
Pest status: Nil
Short Notes: Gymnosperm
Description: Cycas platyphylla is a cycad with stems 2-4m tall and 30 cm diameter, with a swollen base. In the early stages of leaf development, the leaves are strongly bluish green and covered in orange-brown hairs. The mature leaves are 0.5-1.1m long, strongly keeled (V-shaped) in cross-section, and with 120-260 leaflets that are inserted at 45-60 degrees along the rhachis (central stem). The leaves are dark green to yellowish-green, and semi-glossy. The petioles (leaf stalks) are 12-24cm long and have spines for 60-100 percent of their length. The median leaflets are 9-17cm long, 4-6mm wide and narrowed to 3-4mm at the base. The leaflets are arranged 5-10mm apart, hairless, with the margins recurved, the apex abruptly acute, and the midrib flat above and raised below. The lower leaflets leaflets are abruptly replaced by a series of short thorns.
The male pollen cones are ovoid (egg-shaped), 15-20cm long, 8-11cm in diameter, brown and hairy. The scales arranged around the male cone are 30-35mm long, 9-13mm wide and have a spine 6-9mm long at the tip. The female sporophylls (megasporophylls) are 16-32cm long, each with 4-6 ovules. The megasporophyll apical lobes are ovate to lance-shaped, 50-80mm long, 16-37mm wide, regularly toothed with 30-36 lateral spines up to 2mm long and 1mm wide, and have an apical spine 20-25mm long. The seeds are ovoid to globular, 30-40mm long and 27-38mm wide, green to yellowish and densely powdery.
This species can be distinguished from the related C. cairnsiana and C. media subsp. banksia by the initially bluish leaves that become yellow-green with age; the moderately broad leaflets with recurved leaflet margins, and the broad megasporophyll lobes. (Hill 1998; DEWHA 2008)
Map: View Map
Habitat: Cycas platyphylla occurs in open grassy woodland dominated by ironbark, in shallow loamy soils on stony slopes, over acid to intermediate volcanic soils. (Hill 1998; DEWHA 2008)
Reproduction: Male cones shed pollen and female sporophylls are receptive in November - December. Pollination is effected by small beetles in an obligate mutualism.
Management documents: Conservation and management of protected plants in trade in Queensland 1995-1998. Department of Environment.
Notes: Contributors: Ailsa Holland, Paul Forster, Mellisa Mayhew 17/06/2009
References: Department of the Environment, Water, Heritage and the Arts (2008). Cycas platyphylla in Species Profile and Threats Database, Department of the Environment, Water, Heritage and the Arts, Canberra. Accessed 08/12/2008. http://www.environment.gov.au/cgi-bin/sprat/public/sprat.pl
Herbrecs (2008). Cycas platyphylla, in BriMapper version 3.2.1. Queensland Herbarium. Accessed 16/12/2008.
Hill, K. (1992). A preliminary account of Cycas (Cycadaceae) in Queensland. Telopea 5(1): 177-206.
Hill, K.D. in McCarthy, P.M. (Ed) (1998). Flora of Australia 48: 612.
Jones, D.L. (2002). Cycads of the World, Ancient Plants in Today's Landscape. edn 2. New Holland Publishers, Australia.
Profile author: Ailsa Holland (17/06/2009)