Australian Systematic Botany Australian Systematic Botany Society
Taxonomy, biogeography and evolution of plants

Evolution of the south-western Pacific genus Melicytus (Violaceae): evidence from DNA sequence data, cytology and sex expression

A. D. Mitchell A , P. B. Heenan B E , B. G. Murray C , B. P. J. Molloy B and P. J. de Lange D
+ Author Affiliations
- Author Affiliations

A University of Otago, Christchurch, PO Box 4345, Christchurch Mail Centre, Christchurch 8140, New Zealand.

B Allan Herbarium, Landcare Research, PO Box 40, Lincoln 7640, New Zealand.

C School of Biological Sciences, The University of Auckland, Private Bag 92019, Auckland Mail Centre, Auckland 1142, New Zealand.

D Research, Development and Information, Department of Conservation, Private Bag 68908, Newton, Auckland 1145, New Zealand.

E Corresponding author. Email:

Australian Systematic Botany 22(3) 143-157
Submitted: 11 September 2008  Accepted: 12 March 2009   Published: 10 June 2009


Phylogenetic analyses of nuclear DNA external transcribed spacer (ETS) and chloroplast DNA trnL–trnF markers were undertaken to reconstruct the evolutionary history of the South Pacific genus Melicytus. Bayesian analyses of the ETS sequence data produced a phylogenetic tree with several well supported groups, including clades comprising: (1) species from Australia, Tasmania and Lord Howe Island; (2) the Norfolk Island M. latifolius and New Zealand off-shore island M. novae-zelandiae subsp. novae-zelandiae; (3) the large-leaved M. ramiflorus complex; (4) M. fasciger and M. micranthus; and (5) M. obovatus and allies from the Cook Strait region. Phylogenetic analysis of trnL–trnF sequence data also retrieved some of these groups although, in general, was not as well resolved. The relationships of M. lanceolatus are equivocal, as in the ETS phylogeny it is sister to a clade comprising the large-leaved tree species M. fasciger and M. ramiflorus complex and the small-leaved M. micranthus, whereas in the trnL–trnF phylogeny it is sister to a clade of small-leaved shrub species such as M. alpinus and M. crassifolius. Several biogeographic patterns are evident, with dispersal to the west from New Zealand, to Australia, involving small-leaved shrub species. Dispersal to the north from New Zealand, to Norfolk Island and Fiji, involves large-leaved tree species. The sex expression is documented for all named species and undescribed entities, with these being either hermaphroditic or dioecious. When sex expression is mapped onto the phylogeny, the hermaphroditic system is inferred to have evolved from the dioecious system. New chromosome counts are presented for M. angustifolius (2n = 64) and M. dentatus (2n = 32), and earlier counts of 2n = 64 are confirmed for M. crassifolius and M. alpinus. An additional 17 counts are provided for two natural hybrids and several undescribed entities from Australia and New Zealand. The polyploid chromosome number of 2n = 64 occurs most frequently in small-leaved divariate plants with hermaphroditic flowers. When chromosome numbers are plotted onto the phylogeny it is inferred that high polyploids (e.g. 2n = 64) and small-leaved shrubs have evolved from large-leaved trees with functional diploid (e.g. 2n = 32) chromosome numbers.


We thank Adrian Paterson (CHEARS Marsden) for discussion in regard to the molecular clock methods; David Purcell for propagating and growing the cultivated plants; Alex Buchanan (HO) for field assistance in obtaining material of Melicytus angustifolius in Tasmania; Neville Walsh for helpful discussion; staff from Australian National Botanic Garden Canberra, Mt Tomah Botanic Garden, New Zealand Department of Conservation, and landholders in Australia and NZ for permission to collect plant material; Christine Bezar, Dr Rob Smissen and Dr Henry Connor for comments on the draft manuscript; Dr Jacqui Keenan for kindly sharing her laboratory space at the University of Otago, Christchurch; and herbarium staff at AK, CANB, CHR, MEL, WELT. Funds for this research were provided to ADM by the Marsden Fund and to PBH by the New Zealand Foundation for Research Science and Technology through the Defining New Zealand’s Land Biota OBI.


Allan HH (1927) Illustrations of wild hybrids in the New Zealand flora IV. Genetica 9, 499–515.
CrossRef |

Allan HH (1961) ‘Flora of New Zealand. Vol. 1.’ (Government Printer: Wellington)

Altekar G, Dwarkadas S, Huelsenbeck JP, Ronquist F (2004) Parallel Metropolis coupled Markov chain Monte Carlo for Bayesian phylogenetic inference. Bioinformatics 20, 407–415.
CrossRef | CAS | PubMed |

Bennett EM (1972) A revision of the Australian species of Hybanthus Jaequin (Violaceae). Nuytsia 1, 218–241.

Beuzenberg EJ (1961) Observations on sex differentiation and cytotaxonomy of the New Zealand species of the Hymenantherinae (Violaceae). New Zealand Journal of Science 4, 337–349.

Beuzenberg EJ, Hair JB (1959) Contributions to a chromosome atlas of the New Zealand flora – 3. New Zealand Journal of Science and Technology 2, 531–538.

Bowler JM (1982) Aridity in the late Tertiary and Quaternary of Australia. In ‘Evolution of the flora and fauna of arid Australia’. (Eds WR Barker, PJM Greenslade) pp. 35–45. (Peacock Publications: Adelaide)

Carr GD (1985) Additional chromosome numbers of Hawaiian plants. Pacific Science 39, 302–306.

Connor HE, Edgar E (1987) Name changes in the indigenous New Zealand flora, 1960–1986 and Nomina Nova IV, 1983–1986. New Zealand Journal of Botany 25, 115–170.

Crisp M, Cook L, Steane D (2004) Radiation of the Australian flora: what can comparisons of molecular phylogenies across multiple taxa tell us about the evolution of diversity in present-day communities? Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences 359, 1551–1571.
CrossRef | PubMed |

Davis CC, Webb CO, Wurdack KJ, Jaramillo CA, Donoghue MJ (2005) Explosive radiation of Malphighales supports a mid-Cretaceous origin of modern tropical rain forests. American Naturalist 165, E36–E65.
CrossRef | PubMed |

Dawson MI (1995) Contributions to a chromosome atlas of the New Zealand flora – 33. Miscellaneous species. New Zealand Journal of Botany 33, 477–487.

Dawson MI (2000) Index of chromosome numbers of indigenous New Zealand spermatophytes. New Zealand Journal of Botany 38, 47–150.

Dawson MI, Beuzenberg E (2000) Contributions to a chromosome atlas of the New Zealand flora – 36. Miscellaneous families. New Zealand Journal of Botany 38, 1–23.

Doyle JJ, Doyle JL (1987) A rapid isolation procedure from small quantities of fresh leaf tissue. Phytochemical Bulletin 19, 11–15.

Endress PK (2001) The flowers in extant basal angiosperms and inferences on ancestral forms. International Journal of Plant Sciences 162, 1111–1140.
CrossRef |

Feng M (2005) Floral morphogenesis and molecular systematics of the family Violaceae. PhD Dissertation. College of Arts and Sciences, Ohio University, OH.

Green PS (1969) Notes on Melanesian plants: I. Kew Bulletin 23, 337–346.
CrossRef |

Green PS (1970) Notes relating to the floras of Norfolk and Lord Howe Islands, I. Journal of the Arnold Arboretum. Arnold Arboretum 51, 204–220.

Hair JB (1966) Biosystematics of the New Zealand flora 1945–1964. New Zealand Journal of Botany 4, 559–595.

Hall TA (1999) BioEdit: a user-friendly biological sequence alignment editor and analysis program for Windows 95/98/NT. Nucleic Acids Symposium Series 41, 95–98.

Heenan PB, Mitchell AD, McLenachan PA, Lockhart PJ, de Lange PJ (2007) Natural variation and conservation of Lepidium sisymbrioides Hook. f. and L. solandri Kirk (Brassicaceae) in South Island, New Zealand, based on morphological and DNA sequence data. New Zealand Journal of Botany 45, 237–264.

Huelsenbeck JP, Ronquist F (2001) MRBAYES: Bayesian inference of phylogeny. Bioinformatics 17, 754–755.
CrossRef | CAS | PubMed |

Jackson RC (1973) Chromosome evolution in Haplopappus gracilis: a centric transposition race. Evolution 27, 243–256.
CrossRef |

James TA (1990) Violaceae. In ‘Flora of New South Wales. Vol. 1’. (Ed. GJ Harden) pp. 435–441. (New South Wales University Press: Sydney)

Jones JG, McDougall J (1973) Geological history of Norfolk and Philip Islands, southwest Pacific Ocean. Journal of the Geological Society of Australia 20, 239–257.

Kass RE, Raftery AE (1995) Bayes factors. Journal of the American Statistical Association 90, 773–795.
CrossRef |

Kellogg EA, Weitzman AL (1985) A note on the oceanic species of Melicytus (Violaceae). Journal of the Arnold Arboretum 66, 491–502.

Levin DA (2002) ‘The role of chromosomal change in plant evolution.’ (Oxford University Press: Oxford, UK)

Mabberley DJ (2000) The botanical magazine and George Bond’s drawings of Allan Cunningham’s Australian plants. Curtis’s Botanical Magazine 17, 226–235.
CrossRef |

McDougall I, Embleton JJ, Stone DB (1981) Origin and evolution of Lord Howe Island, south west Pacific Ocean. Journal of the Geological Society of Australia 28, 155–176.

McGlone MS, Neall VE (1994) The late Pleistocene and Holocene vegetation history of Taranaki, North Island, New Zealand. New Zealand Journal of Botany 32, 251–269.

Mitchell AD, Heenan PB, Paterson AM (2009) Phylogenetic relationships of Geranium species indigenous to New Zealand. New Zealand Journal of Botany 47, 21–31.

Molloy BPJ, Clarkson BD (1996) A new, rare species of Melicytus (Violaceae) from New Zealand. New Zealand Journal of Botany 34, 431–440.

Molloy BPJ, Druce AP (1994) A new species name in Melicytus (Violaceae) from New Zealand. New Zealand Journal of Botany 32, 113–118.

Murray BG, de Lange PJ (1999) Contributions to a chromosome atlas of the New Zealand flora – 35. Miscellaneous families. New Zealand Journal of Botany 37, 511–521.

Page RDM (1996) TreeView: an application to display phylogenetic trees on personal computers. Computer Applications in the Biological Sciences 12, 357–358.

Parker JS, Clark MS (1991) Dosage sex-chromosome systems in plants. Plant Science 80, 79–92.
CrossRef |

Peng C-I, Chen Y-F (1985) Hybanthus Jacq. (Violaceae), a new generic record for the flora of Taiwan. Botanical Bulletin of Academia Sinica 26, 213–220.

Pinto-Magiio CAF, Pierozzi NL, Castro SCP, Soares-Scott MD (1997) IOPB chromosome data 11. International Organisation of Plant Biosystematists Newsletter 26/27, 23–24.

Posada D, Crandall KA (1998) MODELTEST: testing the model of DNA substitution. Bioinformatics 14, 817–818.
CrossRef | CAS | PubMed |

Powelsland MH (1984) Reproductive biology of three species of Melicytus (Violaceae) in New Zealand. New Zealand Journal of Botany 22, 81–94.

Rambaut A , Drummond AJ (2007) ‘Tracer v1.4.’ Available at [Accessed August 2004].

Raven P (1975) The bases of angiosperm phylogeny: cytology. Annals of the Missouri Botanical Garden 62, 724–764.
CrossRef |

Richards AJ (1997) ‘Plant breeding systems.’ (Chapman & Hall: London)

Ronquist F, Huelsenbeck JP (2003) MRBAYES 3: bayesian phylogenetic inference under mixed models. Bioinformatics 19, 1572–1574.
CrossRef | CAS | PubMed |

Sarkar AK, Chakraverty M, Das SK, Pal CR, Hazara D (1980) Chromosome number reports LXVII. Taxon 29, 358–360.

Smith AC (1978) Precursor to flora of Fiji. Allertonia 1, 331–414.

Smith AC (1981) Violaceae. Flora Vitiensis Nova 2, 655–722.

St John H (1952) Monograph of the genus Isodendrion (Violaceae). Hawaiian plant studies 21. Pacific Science VI, 213–255.

Swofford DL (2001) ‘PAUP*: phylogeny analysis using parsimony (*and other methods). Version 4.0b10 for 32 bit Microsoft Windows.’ (Sinauer Associates Inc.: Sunderland, MA)

Taberlet P, Geilly L, Pantou G, Bouvet J (1991) Universal primers for amplification of three non-coding regions of chloroplast DNA. Plant Molecular Biology 17, 1105–1109.
CrossRef | CAS | PubMed |

Thompson JD, Gibson TJ, Plewniak F, Jeanmougin F, Higgins DG (1997) The ClustalX Windows interface: flexible strategies for multiple sequence alignment aided by quality analysis tools. Nucleic Acids Research 25, 4876–4882.
CrossRef | CAS | PubMed |

Tonkinson D (1996) Hymenanthera. In ‘Flora of Victoria. Vol. 3. Dicotyledons: Winteraceae to Myrtaceae’. (Eds NG Walsh, TJ Entwisle) p. 370. (Inkata Press: Melbourne)

Wagner WL, Herbst DR, Sohmer SH (1990) Violaceae. Manual of the flowering plants of Hawai’i. Vol. 2. Bishop Museum Special Publication 8, 1327–1337.

Wardle P (1978) Origin of the New Zealand mountain flora, with special reference to trans-Tasman relationships. New Zealand Journal of Botany 16, 535–550.

Whistler WA (2004) ‘Rainforest trees of Samoa.’ (Ilse Botanica: Honolulu, HI)

Wright SD, Young CG, Keeling DJ, Dawson JW, Gardner RC (2001) Stepping stones to Hawaii: a transequatorial dispersal pathway for Metrosideros (Myrtaceae) inferred from nrDNA (ITS + ETS). Journal of Biogeography 28, 769–774.
CrossRef |

Xia X, Xie Z (2001) DAMBE: data analysis in molecular biology and evolution. Journal of Heredity 92, 371–373.
CrossRef | CAS | PubMed |

Export Citation Cited By (10)

View Altmetrics