A revision of Australia’s hammer orchids (Drakaea: Orchidaceae), with some field data on species-specific sexually deceived wasp pollinators
Stephen D. Hopper A C and Andrew P. Brown BA Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, UK.
B Department of Environment and Conservation, Species and Communities Branch, Locked Bag 104, Bentley Delivery Centre, WA 6983, Australia.
C Corresponding author. Email: s.hopper@rbgkew.org.uk
Australian Systematic Botany 20(3) 252-285 https://doi.org/10.1071/SB06033
Submitted: 3 October 2006 Accepted: 22 January 2007 Published: 22 June 2007
Abstract
Drakaea Lindley, 1840 is a genus of 10 species of geophytic orchids endemic to the South-west Australian Floristic Region. The genus is renowned for its morphological and chemical adaptations, achieving pollination by sexual deception of male thynnid wasps. The history of taxa in Drakaea has been one of dispute and confusion right to the present day. Here we provide a revision of the genus, the first made by using modern collections and field data, formalising names for undescribed taxa featured by Hoffman and Brown (1992, 1998), several of which are threatened with extinction. We describe six new species: D. andrewsiae, D. concolor, D. confluens, D. gracilis, D. isolata and D. micrantha. Experimental baiting of male wasps has helped show the specific status of some of these new taxa. Molecular phylogenetic research is needed to clarify relationships and patterns of speciation in the genus. Five of the 10 Drakaea species are legally protected under the Western Australian Wildlife Conservation Act and the Commonwealth Environment Protection and Biodiversity Conservation Act, signalling the ongoing need for research and management to ensure the conservation of this unique part of Australia’s orchid heritage. D. andrewsiae has been recorded only three times from the Gnowangerup–Tunney district. Urgent surveys are needed to establish its conservation status.
Acknowledgements
We are grateful to many members of the WA Native Orchid Study and Conservation Group who have assisted our research on Drakaea over the past two decades, Sue Patrick for line drawings, Paul Wilson for Latin diagnoses and Bill Barker for photos of the type of D. andrewsiae at AD. The late Ron Heberle kindly provided a copy of the late Herb Foote’s photo of this elusive species. Garry Brockman alerted us to his rediscovery of D. andrewsiae. Graham Brown kindly identified wasp vouchers for us. Maps were derived and modified from the Australian Virtual Herbarium. For access to specimens we thank the Directors and staff of the following Australian and European Herbaria: AD, BRI, CANB, HO, KEW, MEL, NSW, PERTH, W. Successive Curators, Directors and staff of the Western Australian Herbarium have helped in numerous ways with our research. Two referees suggested material improvements to the manuscript.
Blaxell DF
(1972)
Arthrochilus F.Muell. and related genera (Orchidaceae) in Australasia. Contributions from the New South Wales National Herbarium 4, 275–283.
Bower CC
(1996) Demonstration of pollinator-mediated reproductive isolation in sexually deceptive species of Chiloglottis (Orchidaceae: Caladeniinae). Australian Journal of Botany 44, 15–33.
| Crossref | GoogleScholarGoogle Scholar |
Clements MA
(1989) Catalogue of Australian Orchidaceae. Australian Orchid Research 1, 1–160.
Clements MA,
Jones DL,
Sharma IK,
Nightingale ME,
Garratt MJ,
Fitzgerald KJ,
Mackenzie AM, Molloy BPJ
(2002) Phylogenetics of Diurideae (Orchidaceae) based on the internal transcribed spacer (ITS) regions of nuclear ribosomal DNA. Lindleyana 17, 135–171.
Drummmond J
(1838) Remarks on the roots of some of the terrestrial Orchideae of Australia found in the neighbourhood of the Swan River. Gardener’s Magazine [London] 14, 425–429.
Drummond J
(1842) Botanical intelligence from the Swan River. Journal of Botany, London 1, 628–635.
Fitzgerald RD
(1882) New Australian orchids. The Gardeners’. Chronicle and Agricultural Gazette 17, 494–495.
George AS
(1971) A check list of the Orchidaceae of Western Australia. Nuytsia 1, 166–207.
George AS
(1984) Seven new orchids from Western Australia. Nuytsia 5, 53–62.
Hopper SD, Brown AP
(2004) Robert Brown’s Caladenia revisited, including a revision of its sister genera Cyanicula, Ericksonella and Pheladenia (Caladeniinae: Orchidaceae). Australian Systematic Botany 17, 171–240.
| Crossref | GoogleScholarGoogle Scholar |
Hopper SD, Brown AP
(2006) Australia’s wasp-pollinated flying duck orchids revised (Paracaleana: Orchidaceae). Australian Systematic Botany 19, 211–244.
| Crossref | GoogleScholarGoogle Scholar |
Hopper SD, Gioia P
(2004) The Southwest Australian Floristic Region: evolution and conservation of a global hotspot of biodiversity. Annual Review of Ecology Evolution and Systematics 35, 623–650.
| Crossref | GoogleScholarGoogle Scholar |
Kores PJ,
Molvray M,
Weston PH,
Hopper SD,
Brown AP,
Cameron KM, Chase MW
(2001) A phylogenetic analysis of Diurideae (Orchidaceae) based on plastid DNA sequence data. American Journal of Botany 88, 1903–1914.
| Crossref |
Mant J,
Brown GR, Weston PH
(2005a) Opportunistic pollinator shifts among sexually deceptive orchids indicated by a phylogeny of pollinating and non-pollinating thynnine wasps (Tiphiidae). Biological Journal of the Linnean Society 86, 381–395.
| Crossref | GoogleScholarGoogle Scholar |
Mant J,
Peakall R, Weston PH
(2005b) Specific pollinator attraction and the diversification of sexually deceptive Chiloglottis (Orchidaceae). Plant Systematics and Evolution 253, 185–200.
| Crossref | GoogleScholarGoogle Scholar |
Mant J,
Bower CC,
Weston PH, Peakall R
(2005c) Phylogeography of pollinator-specific sexually deceptive Chiloglottis taxa (Orchidaceae): evidence for sympatric divergence? Molecular Ecology 14, 3067–3076.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Mant JG,
Schiestl FP,
Peakall R, Weston PH
(2002) A phylogenetic study of pollinator conservatism among sexually deceptive orchids. Evolution 56, 888–898.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Mueller FJH
(1858) Arthrochilus. Fragmenta Phytographiae Australiae 1, 42.
Peakall R
(1990) Responses of male Zaspilothynnus trilobatus Turner wasps to females and the sexually deceptive orchid it pollinates. Functional Ecology 4, 159–167.
| Crossref | GoogleScholarGoogle Scholar |
Pridgeon AM
(1994) Systematic leaf anatomy of Caladeniinae (Orchidaceae). Botanical Journal of the Linnean Society 114, 31–48.
| Crossref | GoogleScholarGoogle Scholar |
Ramsay RR,
Dixon KW, Sivasithamparam K
(1986) Patterns of infection and endophytes associated with Western Australian orchids. Lindleyana 1, 203–214.
Rogers RS
(1920) Contributions to Australian orchidology. Transactions and Proceedings of the Royal Society of South Australia 44, 322–359.
Rogers RS
(1926) The genus Spiculaea, Lindl., and its taxonomic relationships. Victorian Naturalist 43, 179–183.
Schlechter FRR
(1921)
Drakaea fitzgeraldii. Repertorium Novarum Specierum Regni Vegetabilis 17, 81.
Stoutamire WP
(1974) Australian terrestrial orchids, thynnid wasps, and pseudocopulation. American Orchid Society Bulletin 43, 13–18.
Stoutamire WP
(1975) Pseudocopulation in Australian terrestrial orchids. American Orchid Society Bulletin 44, 226–233.
Stoutamire WP
(1981) Pollination studies in Australian terrestrial orchids. National Geographic Society Research Reports 13, 591–598.
Wells AG
(1981) Wasp’s mating instincts aids orchid pollination. Swans 11, 15–17.
Wells AG
(1987) The dilemma of a flower wasp. Australian Natural History 22, 249–253.