Taxonomic Revision Of Stranvaesia And Photinia (Rosaceae)

Photinia Lindl.and Stranvaesia Lindl.belong to Rosaceae-Maleae.Thirty-five species have been recognised in the genus Photinia,species of which are evergreen trees or shrubs,and disjuncted between East and Southeast Asia and North America.Stranvaesia is a small genus with only five species that are trees or shrubs.Three species of Stranvaesia are evergreen and the rest two species are deciduous.The main systematic problems of Photinia and Stranvaesia include the following aspects: First,the relationship between Photinia,Stranvaesia and Heteromeles M.Roem.is uncertain and controversial.Second,the current system within Photinia mainly based on morphological characters,and should be revised comprehensively on the basis of leaf epidermis micromorphology,palynology and molecular phylogeny.Third,there are many species with similar morphological characters in Photinia and Stranvaesia,and the boundaries between these species deserve further study.Fourth,names of Photinia and Stranvaesia have not been systematically identified since they were described.In order to solve those problems above,studies involving checking the original materials,the herbarium specimens and field investigations combined with the leaf epidermis micromorphology,palynology and molecular phylogeny have been made.The main results are as follows.First,a phylogeny involving Photinia,Stranvaesia,Heteromeles and related taxa based on one nuclear gene PepC and three chloroplast genes trnG-trn S,trnL-trn F and psbA-trnH had been established.The results indicated that neither Photinia nor Stranvaesia was momophyletic group.Stranvaesia specises S.davidiana Decne.was nested with most Photinia species,and should be transferred to Photinia.The deciduous Stranvaesia specises S.amphidoxa C.K.Schneid.and S.tomentosa T.T.Yu & T.C.Ku were nested with Pourthiaea tsaii(Rehder)H.Iketani & H.Ohashi,and should be transferred to Pourthiaea.Moreover,the evergreen Stranvaesia specises S.nussia(Buch.-Ham.ex D.Don)Decne.and S.oblanceolata(Rehder & E.H.Wilson)Stapf were nested with Photinia bodinieri Lévl..S.oblanceolata and P.bodinieri should be merged into S.nussia for the morphological characters of the three species varied continuously.Second,the only species of Heteromeles,H.arbutifolia(Lindl.)M.Roem.,had been transferred to Photinia based on the results of molecular phylogeny.Third,systematic revision about Photinia and Stranvaesia had been made.(1)All the original materials of 269 Photinia and Stranvaesia names had been clearly checked.(2)Species with unclear delimitation had been revised.S.microphylla J.E.Vidal,P.crassifolia Lévl.,P.megaphylla T.T.Yu & T.C.Ku,P.raupingensis K.C.Kuan,P.kwangsiensis H.L.Li and P.glomerata Rehder & E.H.Wilson have been reduced as synonyms of P.davidiana var.undulata(Decne.)Long Y.Wang,W.Guo & W.B.Liao,P.beckii C.K.Schneid.,P.wardii C.E.C.Fisch.,P.prunifolia(Hooker & Arnott)Lindl.,P.chingiana Hand.-Mazz.and P.griffithii Decne.respectively.(3)Four new combinations including Pourthiaea amphidoxa var.amphileia(Hand.-Mazz.)Long Y.Wang,W.Guo & W.B.Liao,P.tomentosa(T.T.Yu & T.C.Ku)Long Y.Wang,W.Guo & W.B.Liao,Photinia davidiana var.undulata(Decne.)Long Y.Wang,W.Guo & W.B.Liao and P.hintonii(Phipps)Long Y.Wang,W.Guo & W.B.Liao had been proposed.(4)Eighteen names such as H.arbutifolia var.cerina(Jeps.)A.E.Murray,H.arbutifolia var.macrocarpa(Munz)Munz,P.arbutifolia var.cerina Jepson,P.arbutifolia var.macrocarpa Munz,P.bodinieri Lévl.,P.bodinieri var.longifolia Card.,P.crassifolia Lévl.,P.glomerata Rehder & E.H.Wilson,P.kwangsiensis H.L.Li,P.lasiogyna var.glabrescens L.T.Lu & C.L.Li,P.megaphylla T.T.Yu & T.C.Ku,P.microcarpa subsp.elliptica Phipps,P.microcarpa subsp.hintonii Phipps,P.microcarpa Subsp.hintonii var.brevis Phipps,P.prunifolia var.denticulata T.T.Yu,P.raupingensis K.C.Kuan,S.microphylla Vidal and S.oblanceolata(Rehder & E.H.Wilson)Stapf had been reduced as synonyms.(5)Lectotypes of twelve names such as P.undulata var.formosana Cardot,P.notoniana var.ceylanica Hook.f.,P.notoniana var.macrophylla Hook.f.,P.lindleyana Wight & Arn.,P.glabra var.chinensis Maxim.,P.crassifolia Lévl.,P.prunifolia(Hooker & Arnott)Lindl.,P.raupingensis K.C.Kuan,P.loriformis W.W.Smith,P.stenophylla Hand.-Mazz.,P.taishunensis G.H.Xia,L.H.Lou & S.H.Jin and P.prionophylla(Franch.)C.K.Schneid.had been designated in this thesis.