Testing the monophyly of Aesculus L. and Billia Peyr., woody genera of tribe Hippocastaneae of the Sapindaceae.
Hippocastaneae is a well-supported clade in Sapindaceae that comprises 15+ species; 12+ in Aesculus, two in Billia, and one in Handeliodendron Rehder. The monophyly of Aesculus and Billia were widely assumed, but a recent molecular phylogenetic study of Sapindanceae used seven species of Aesculus and one each of Billia and Handeliodendron and showed that Billia and Handeliodendron were nested within Aesculus. Here, we tested the hypothesis that Aesculus and Billia are mutually monophyletic using phylogenetic analyses of seven molecular markers and 31 accessions of Hippocastaneae representing 14 species. We performed phylogenetic analyses using a dataset of concatenated genes as well as with coalescent method for constructing a species tree from individual gene trees. The analysis of seven concatenated markers and the species tree strongly supported the mutual monophyly of Aesculus and Billia. We also recovered support for the traditional arrangement of genera within Hippocastaneae: Aesculus and Billia comprising a clade that is sister to Handeliodendron. However, the relationships among the genera remain incompletely resolved.
Oklahoma State University, Department of Botany, 301 Physical Sciences, Stillwater, OK 74078, USA. Electronic address: aj.harris@inbox.com.
A J
AJ
Harris
Zhejiang University, College of Life Sciences, Hangzhou 310058, China.
Chengxin
C
Fu
North Carolina State University, Department of Plant and Microbial Biology, 2115 Gardner Hall, Campus Box 7612, Raleigh, NC 27695, USA.
Qiu-Yun Jenny
QY
Xiang
Oklahoma State University, Department of Botany, 301 Physical Sciences, Stillwater, OK 74078, USA.
LaRinda
L
Holland
National Museum of Natural History, Department of Botany, MRC 166, Smithsonian Institution, Washington, DC 20013-7012, USA.
Jun
J
Wen
D031319:Aesculus / Q000145:classification / Q000235:genetics*; D002736:Chloroplasts / Q000235:genetics; D018744:DNA, Plant / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D031318:Hippocastanaceae / Q000145:classification / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D018515:Plant Leaves / Q000235:genetics; D029631:Sapindaceae / Q000145:classification / Q000235:genetics; D017422:Sequence Analysis, DNA
D018744:DNA, Plant
Aesculus; Billia; Handeliodendron; Hippocastaneae; Phylogeny; Sapindaceae