Himmelreich, Sven and Breitwieser, Ilse and Oberprieler, Christoph (2012) Phylogeny, biogeography, and evolution of sex expression in the southern hemisphere genus Leptinella (Compositae, Anthemideae). MOLECULAR PHYLOGENETICS AND EVOLUTION, 65 (2). pp. 464-481. ISSN 1055-7903, 1095-9513
Full text not available from this repository. (Request a copy)Abstract
Leptinella is exceptional in the Anthemideae (Compositae) in its evolution of dimorphic sex expression. A molecular phylogeny including 40 of its 42 described taxa based on nucleotide sequences from two plastid regions (psbA-trnH and trnC-petN spacers) and one nuclear marker (nrDNA ITS) is presented. Phylogenetic reconstruction was hampered by inadequate phylogenetic signal indicating recent radiation of species during the last 5 Ma and high level of reticulate evolution presumably caused by hybridisation and polyploidisation. Nevertheless, Leptinella is nested within a paraphyletic genus Cotula that also engulfs the South American genus Soliva. Within Leptinella, the highly polyploid and sexually polymorphic subgenus Leptinella is monophyletic, while subgenus Oligoleima as well as subgenus Radiata are polyphyletic. We found a basal split between a lineage of Australian and New Guinean taxa and one of largely New Zealand taxa. At least five long-distance dispersal events have to be assumed in order to explain the distribution pattern in Leptinella. Among those, one is from New Zealand to Australia, while the others are dispersals to South America and to several subantarctic islands. The phylogeny presented here indicates that the ancestral sex expression in Leptinella is monoecy and that dioecy and paradioecy are derived conditions. High ploidy is especially common in the dioica-group, where dioecy is also common. However, the occurrence of a dioecious sex expression in tetraploid representatives of this group and of polyploidy in other clades that only exhibit monoecious or paradioecious conditions indicate that there is no consistent correlation between these two characters. (C) 2012 Elsevier Inc. All rights reserved.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | NEW-ZEALAND FLORA; LONG-DISTANCE DISPERSAL; COTULA L COMPOSITAE; BREEDING SYSTEMS; MOLECULAR EVIDENCE; CHLOROPLAST DNA; TERRESTRIAL FAUNA; NONCODING REGIONS; GENDER DIMORPHISM; UNIVERSAL PRIMERS; Dioecy; Hybridisation; Monoecy; New Zealand; Paradioecy; Polyploidy |
| Subjects: | 500 Science > 580 Botanical sciences |
| Divisions: | Biology, Preclinical Medicine > Institut für Pflanzenwissenschaften > Group Plant Systematics and Evolution (Prof. Dr. Christoph Oberprieler) |
| Depositing User: | Dr. Gernot Deinzer |
| Date Deposited: | 05 May 2020 05:00 |
| Last Modified: | 05 May 2020 05:00 |
| URI: | https://pred.uni-regensburg.de/id/eprint/17908 |
Actions (login required)
 |
View Item |
