New chromosome numbers in Homoranthus (Myrtaceae: Chamelaucieae) and notes on their taxonomic utility
Lachlan M. Copeland A C , Jeremy J. Bruhl A , Lyn A. Craven B and Curt L. Brubaker BA Botany, Centre for Ecology, Evolution and Systematics, University of New England, Armidale, NSW 2351, Australia.
B CPBR, CSIRO Plant Industry, GPO Box 1600, Canberra, ACT 2601, Australia.
C Corresponding author. Email: lcopela3@une.edu.au
Australian Systematic Botany 21(6) 443-447 https://doi.org/10.1071/SB08036
Submitted: 8 August 2008 Accepted: 20 October 2008 Published: 23 December 2008
Abstract
Diploid chromosome counts are reported for the first time for 23 species of Homoranthus (Myrtaceae) and published counts are confirmed for a further three species. H. wilhelmii (F.Muell.) Cheel was determined as having 2n = 14, which contrasts with an earlier report of n = 6 for the species. Dysploidy appears to be common within the genus, with diploid chromosome numbers of 2n = 14, 16, 18 and 20 being recorded. There was no evidence of recent polyploidy within Homoranthus nor of any infraspecific dysploidy. Chromosome numbers appear to be a useful taxonomic tool to confirm the distinctness of some morphologically similar taxa but may be of limited use in estimating phylogenetic relationships.
Acknowledgments
We thank Peter Wilson, Barbara Briggs, Ian Telford, Mike Ramsey and Nallamilli Prakash for useful discussions on the systematics of Homoranthus and/or the most appropriate methods to observe their chromosomes. The directors of BRI, CANB, MEL, NE and NSW are thanked for allowing access to their collections of Homoranthus. LMC gratefully acknowledges the financial support received from an Australian Postgraduate Award (APA), the Noel C. W. Beadle and Friends of Botany Scholarships, and the Australian Biological Resources Study (ABRS). We also thank the NSW National Parks and Wildlife Service and the Queensland Parks and Wildlife Service for allowing us to collect plant material in their reserves.
Atchison E
(1947) Chromosome numbers in the Myrtaceae. American Journal of Botany 34, 159–164.
| Crossref | GoogleScholarGoogle Scholar |
[Accessed 7 December 2006].
Hilu KW
(2004) Phylogenetics and chromosomal evolution in the Poaceae (grasses). Australian Journal of Botany 52, 13–22.
| Crossref | GoogleScholarGoogle Scholar |
CAS |
Hunter JT, Copeland LM
(2001) Homoranthus binghiensis (Myrtaceae: Chamaelaucieae), a new species from the North Western Slopes of New South Wales. Telopea 9, 431–433.
Jones K
(1970) Chromosome changes in plant evolution. Taxon 19, 172–179.
| Crossref | GoogleScholarGoogle Scholar |
Rye BL
(1979) Chromosome number variation in the Myrtaceae and its taxonomic implications. Australian Journal of Botany 27, 547–573.
| Crossref | GoogleScholarGoogle Scholar |
Smith-White S
(1950) Cytological studies in the Myrtaceae III. Cytology and phylogeny in the Chamaelaucoideae. Proceedings of the Linnean Society of New South Wales 75, 99–121.
Smith-White S
(1954a) Cytological studies in the Myrtaceae IV. The sub-tribe Euchamaelaucinae. Proceedings of the Linnean Society of New South Wales 79, 21–28.
Smith-White S
(1954b) Chromosome numbers in the Boronieae (Rutaceae) and their bearing on the evolutionary development of the tribe in the Australian flora. Australian Journal of Botany 2, 287–303.
| Crossref | GoogleScholarGoogle Scholar |
Smith-White S
(1959) Cytological evolution in the Australian flora. Cold Spring Harbor Symposia on Quantitative Biology 24, 273–289.
|
CAS |
PubMed |
Tyagi AP,
McComb J, Considine J
(1991) Cytogenetic and pollination studies in the genus Verticordia DC. Australian Journal of Botany 39, 261–272.
| Crossref | GoogleScholarGoogle Scholar |
Wilson PG,
O’Brien MM,
Heslewood MM, Quinn CJ
(2005) Relationships within Myrtaceae sensu lato based on a matK phylogeny. Plant Systematics and Evolution 251, 3–19.
| Crossref | GoogleScholarGoogle Scholar |
