Systematics Revision Of Anoectochilus(Orchidaceae)

Anoectochilus belongs to Subtrib.Goodyerinae,Trib.Cranichideae,Orchidaceae,with high ornamental and medicinal value.Due to high morphological variation,identification of species in this genus is difficult that makes the use of the species in traditional medicine much confused.At the same time,there was little report about unclear infrageneric relationships and some morphological characteristics are not described completely.This taxonomic study was conducted through morphology and molecular analysis.We observed 337 specimens and selected 30 morphological characters to conduct UPGMA,NJ and PCoA analysis.For the molecular systematics,20 species of 58 samples were referred as innergroup with Zeuxinella vietnamica(Aver.)Aver.)as outgroup that nrDNA ITS,cpDNA matK?trnL-F and rbcL were applied as molecular markers to build the phylogenetic trees by BI,ML,MP methods with 219 sequences(9 sequences are from Genbank).Results were as follows:1.The results of UPGMA,NJ and PCoA analysis were both indicated that the Anoectochilus s.s.could be mainly divided into two clades.Species that having resupinate flowers with 180° torsion and downside labellum clustered within clade ?,whereas species of non-resupinate flowers with 360° torsion and upside labellum clustered within clade ?.2.The phylogenetic results showed that three combined chloroplast gene fragments could get higher resolution of infrageneric relationships than single nuclear DNA ITS.However,some interspecific relationship could not be well analyzed including A.roxburghii,A.longilobus,A.brevilabris,A.zhejiangensis,A.malipoensis,A.nandanensis.3.The phylogenetic results were not strictly consistent with morphological results,which indicated that Anoectochilus could be mainly divided into two clades based on resupinate flowers with 180° torsion or non-resupinate flowers with 360°torsion and labellum direction.4.According to the observation of specimens,we found that five species of Anoectochilus should be moved to Odontochilus.A.pectinatus(Hook.f.)Ridl.,A.flavescens Blume,A.klabatensis(Schltr.)S.Thomas,A.sandvicensis Lindl.,A.sumatranus(J.J.Sm.)J.B.are the homotypic synonyms of O.pectinatus Hook.f.,O.flavescens(Blume)Blume,O.klabatensis Schltr.,O.sandvicensis(Lindl.)Benth.&Hook.f.ex W.F.M.Drake,O.sumatranus J.J.Sm..5.We found that the clour of leaf and veins,the density of vein,labellum direction,the shape and colour of epichile,the colour of mesochile,length,number and colour of mesochile fringes,spur length and the shape of column wings were key characters to distinguish species in Anoectochilus.Finally,39 species of Anoectochilus in the world were confirmed.Keys to species,detailed morphological descriptions with anatomical pictures were provided.It provided comprehensive taxonomic evidence of this genus and will benefit the accurate application of Chinese herbal medicine,the sustainable utilization and protection of the resources.