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Australian Hakea species: identification and information.
SUMMARY
Hakea is an endemic Australian genus of some 150 species and is found in almost all ecological habitats but with a preponderance of species in the south-west of Western Australia and along the eastern coast of Australia. A few species are invasive, particularly in South Africa and New Zealand and some Mediterranean countries. They are variously referred to as needlewoods or corkwoods, or as pincushion, cricket ball or frog Hakeas, to name just a few of their more readily recognised characteristics.
Hakea species are frequently confused with the closely related Grevillea and a quick guide to their distinction is given below together with access to a simple key which distinguishes between the genera.
Fact sheets have been produced for each species and these can be accessed through the key, through the list of species (which includes all accepted names as well as synonyms) or through the list of common names. Each fact sheet has the basic taxonomic treatment taken from the flora account by R.M.Barker, L. Haegi and W.R.Barker in the Flora of Australia volume 17B. This has been supplemented with further information and links by the present author together with a series of images for each species, predominantly from the photographs of Bill Barker and Ivan Holliday. At the time of publication web-links within the fact sheet were up to date, but unfortunately these do change and apologies are extended for those which are no longer operative.
While there is a general distribution statement for each species, distribution maps have not been included in the fact sheets. Distribution within Australia can instead be accessed through Australia’s Virtual Herbarium, the latest version of which also enables mapping of subspecies and varieties.
HAKEA OR GREVILLEA? Lucid Key v1.0
Distinction between species of Hakea and Grevillea is often difficult because they are closely related and may eventually be combined. Most of the characteristics defining both genera are present in a small subset of species of the other genus.
The majority of Hakea species have leaves in which both surfaces are similar in appearance or, if they are terete, they are usually without an obvious groove or grooves for their whole length. Styles and ovaries are, with only 1 or 2 exceptions exceptions, glabrous in Hakea, but so can they be in Grevillea; in this case the presence of hairs can be taken as an indication of Grevillea. Apart from the corkwoods, Hakea species have sessile ovaries and so a stipitate ovary is also an indication of Grevillea. And fruits which are woody and retained for some time on the plant in an unopened state are an immediate indication of Hakea, since the fruits of Grevillea are not woody and not usually retained on the plant. Woody Hakea fruits when they do open usually reveal seeds with an asymmetrical papery wing while the seeds of Grevillea are either symmetrically winged or not winged at all.
This quick key, which is not illustrated in any way, may help in deciding whether the material you are trying to identify is a Hakea or a Grevillea.
IDENTIFICATION OF HAKEA SPECIES
Lucid key v1.0This is an interactive web-based key for all presently known species of Hakea (Proteaceae), a genus which is restricted to Australia, apart from species which are invasive elsewhere.
The key opens with all 163 features listed for identification purposes. It is recommended that the user use the Quick subset of 41 characters initially. Should these 41 features prove to be inadequate to separate species then the other features can be used but they are considered to be less reliable than the Quick subset. Some of the extra features, such as distribution and flowering time, do need to be used with care since they can be changeable with time and place and whether one is dealing with a cultivated specimen or one growing naturally. Any measurements used within the key are based on dried herbarium material and while some allowance has been made for this they may still be lower than those found in fresh or cultivated material.
The basis of the text for the fact sheets came from the species treatment by R.M.Barker, L. Haegi and W.R.Barker in the Flora of Australia volume 17B, now also available online. Direct access to the fact sheets compiled for each species is available through the list of species and synonyms and through the list of common names.
Photographs have been provided primarily by Bill Barker and Ivan Holliday, or as acknowledged. Line illustrations are by Beth Chandler or Kevin Thiele.
The author would be pleased to hear of any errors or omissions or any suggestions for improvements.
ACKNOWLEDGEMENTS
Funding for the building of this key was provided by the Australian Biological Resources Study (ABRS). The basis of the text for the fact sheets, built using Fact Sheet Fusion software, came from the species treatment by R.M.Barker, L. Haegi and W.R.Barker in the Flora of Australia volume 17B, now also available online.
Work was carried out for the most part at the State Herbarium of South Australia (AD). Access to their facilities is gratefully acknowledged. Some time (February to April, 2009) was also spent on this project at the Allan Herbarium (CHR) in Christchurch, New Zealand and again the use of their facilities is acknowledged.
Photographs of the species were provided predominantly by Bill Barker and Ivan Holliday, but also by others acknowledged in the text accompanying the photograph. All of these photographs are copyright and permission should be sought from the copyright holder for their use in any other publications.
Line drawings of features are by Beth Chandler with the exception of a few which were adapted from existing illustrations by Kevin Thiele for the original Lucid key to the Families of Flowering Plants of Australia.
SUGGESTED CITATION
R.M.Barker (2010). Australian Hakea species: identification and information. Version 1. An interactive Lucid key and information system at http://www.flora.sa.gov.au/id_tool.html [accessed on current date in day month year]
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