TY - JOUR
T1 - Systematics of Libinhania, a new endemic genus of Gnaphalieae (Asteraceae) from the Socotra archipelago (Yemen), inferred from plastid, low-copy nuclear and nuclear ribosomal DNA loci
AU - Kilian, Norbert
AU - Galbany-Casals, Mercè
AU - Sommerer, Ronny
AU - Oberprieler, Christoph
AU - Smissen, Rob
AU - Miller, Antony
AU - Rabe, Katharina
PY - 2017/3/1
Y1 - 2017/3/1
N2 - © 2017 The Linnean Society of London. The Socotra archipelago offthe Horn of Africa shelters morphologically diverse endemic species of Asteraceae tribe Gnaphalieae, eight species placed in Helichrysum and five newly discovered. We reconstructed their phylogenetic relationships, analysing nuclear ribosomal DNA (nrDNA) internal transcribed spacer and external transcribed spacer, three plastid DNA and two low-copy nuclear DNA loci with Bayesian inference and maximum parsimony. The plastid DNA and nrDNA trees resolve the endemic helichrysoids as a monophyletic group and agree in that they are not members of Helichrysum or even part of the Helichrysum-Anaphalis-Pseudognaphalium clade, but disagree as to their sister group. In the nrDNA tree, they are nested in the Filago-Leontopodium-Antennaria-Gamochaeta (FLAG) clade, whereas in the plastid DNA tree they are sister to Syncarpha mucronata. The endemic helichrysoids possess two divergent copies of each of the nDNA low-copy markers, similar to those previously found for the FLAG clade. This suggests an ancient allopolyploid origin, with the putative ancestors among the ancestors of Gnaphalium or relatives and of S. mucronata or relatives. The reconstruction of ancestral states of morphological characters suggested hypotheses on the origin and evolution of the morphological diversity of the endemic helichrysoids. We conclude a taxonomic treatment with a key to, and descriptions for, the 13 species accommodated in a new genus, Libinhania.
AB - © 2017 The Linnean Society of London. The Socotra archipelago offthe Horn of Africa shelters morphologically diverse endemic species of Asteraceae tribe Gnaphalieae, eight species placed in Helichrysum and five newly discovered. We reconstructed their phylogenetic relationships, analysing nuclear ribosomal DNA (nrDNA) internal transcribed spacer and external transcribed spacer, three plastid DNA and two low-copy nuclear DNA loci with Bayesian inference and maximum parsimony. The plastid DNA and nrDNA trees resolve the endemic helichrysoids as a monophyletic group and agree in that they are not members of Helichrysum or even part of the Helichrysum-Anaphalis-Pseudognaphalium clade, but disagree as to their sister group. In the nrDNA tree, they are nested in the Filago-Leontopodium-Antennaria-Gamochaeta (FLAG) clade, whereas in the plastid DNA tree they are sister to Syncarpha mucronata. The endemic helichrysoids possess two divergent copies of each of the nDNA low-copy markers, similar to those previously found for the FLAG clade. This suggests an ancient allopolyploid origin, with the putative ancestors among the ancestors of Gnaphalium or relatives and of S. mucronata or relatives. The reconstruction of ancestral states of morphological characters suggested hypotheses on the origin and evolution of the morphological diversity of the endemic helichrysoids. We conclude a taxonomic treatment with a key to, and descriptions for, the 13 species accommodated in a new genus, Libinhania.
KW - Allopolyploidy
KW - Ancestral state reconstruction
KW - Compositae
KW - Helichrysum
KW - Morphology
KW - Phylogenetics
KW - Reticulate evolution
KW - Taxonomy
U2 - 10.1093/botlinnean/bow013
DO - 10.1093/botlinnean/bow013
M3 - Article
VL - 183
SP - 373
EP - 412
JO - Botanical Journal of the Linnean Society
JF - Botanical Journal of the Linnean Society
SN - 0024-4074
IS - 3
ER -