广西植物
廣西植物
엄서식물
GUIHAIA
2015年
2期
143-150,177
,共9页
黎乾坤%张强%邓涛%盘波%黄俞淞%李文兰
黎乾坤%張彊%鄧濤%盤波%黃俞淞%李文蘭
려건곤%장강%산도%반파%황유송%리문란
苦苣苔科%报春苣苔属%新物种%系统发育%matK基因
苦苣苔科%報春苣苔屬%新物種%繫統髮育%matK基因
고거태과%보춘거태속%신물충%계통발육%matK기인
Gesneriaceae%Primulina%new species%phylogeny%matK
报春苣苔是一类生长在石灰岩基质上的多年生草本植物，目前已知的种类160余种，主要分布在我国南部和越南北部的石灰岩地区.该属植物许多种类分布极其狭域，往往仅零星分布在某个或少数几个地点.近年来，该属植物许多新种类不断地被发现和报道，预示着该属植物可能有更加丰富的多样性.该研究报道了在广西博白县发现的该属植物一新种.从形态上判断，该新种属于广义报春苣苔属，其具有的一些特别的形态特征，如花冠下唇比上唇长得多，上唇内部具有两个近圆形斑点(其它多数种类具有条形斑点)，而易于与本属其它物种区分.而且，基于叶绿体 matK 基因序列重建的系统发育关系表明，该新种的确属于报春苣苔属且广义报春苣苔属是单系类群.该新种与钟冠报春(P ．swinglei )和疏花报春(P ．laxiflora )最为近缘，其 matK 基因与后两者分别有5个和11个碱基差异，暗示这些物种间经历了较长时间的独立演化或 matK 基因在这些物种中具有较高的碱基替换速率.另外，该新种只生长在丹霞岩石上，而其近缘种以及同属大多数其它种类都生长在石灰岩基质上，暗示该新种获得了特殊的适应能力以及与其它近缘种间存在生态隔离.该新种以及近年来本属许多其它新种类的发现，进一步增加了对该属植物多样性的认识，以及该属植物的演化与多样性分化之谜.这些物种所具有的高度区域或局域特有性和稀有性，以及形态上的特殊性和遗传上的独立性，进一步强化了对该属植物开展保护的重要性.
報春苣苔是一類生長在石灰巖基質上的多年生草本植物，目前已知的種類160餘種，主要分佈在我國南部和越南北部的石灰巖地區.該屬植物許多種類分佈極其狹域，往往僅零星分佈在某箇或少數幾箇地點.近年來，該屬植物許多新種類不斷地被髮現和報道，預示著該屬植物可能有更加豐富的多樣性.該研究報道瞭在廣西博白縣髮現的該屬植物一新種.從形態上判斷，該新種屬于廣義報春苣苔屬，其具有的一些特彆的形態特徵，如花冠下脣比上脣長得多，上脣內部具有兩箇近圓形斑點(其它多數種類具有條形斑點)，而易于與本屬其它物種區分.而且，基于葉綠體 matK 基因序列重建的繫統髮育關繫錶明，該新種的確屬于報春苣苔屬且廣義報春苣苔屬是單繫類群.該新種與鐘冠報春(P ．swinglei )和疏花報春(P ．laxiflora )最為近緣，其 matK 基因與後兩者分彆有5箇和11箇堿基差異，暗示這些物種間經歷瞭較長時間的獨立縯化或 matK 基因在這些物種中具有較高的堿基替換速率.另外，該新種隻生長在丹霞巖石上，而其近緣種以及同屬大多數其它種類都生長在石灰巖基質上，暗示該新種穫得瞭特殊的適應能力以及與其它近緣種間存在生態隔離.該新種以及近年來本屬許多其它新種類的髮現，進一步增加瞭對該屬植物多樣性的認識，以及該屬植物的縯化與多樣性分化之謎.這些物種所具有的高度區域或跼域特有性和稀有性，以及形態上的特殊性和遺傳上的獨立性，進一步彊化瞭對該屬植物開展保護的重要性.
보춘거태시일류생장재석회암기질상적다년생초본식물，목전이지적충류160여충，주요분포재아국남부화월남북부적석회암지구.해속식물허다충류분포겁기협역，왕왕부령성분포재모개혹소수궤개지점.근년래，해속식물허다신충류불단지피발현화보도，예시착해속식물가능유경가봉부적다양성.해연구보도료재엄서박백현발현적해속식물일신충.종형태상판단，해신충속우엄의보춘거태속，기구유적일사특별적형태특정，여화관하진비상진장득다，상진내부구유량개근원형반점(기타다수충류구유조형반점)，이역우여본속기타물충구분.이차，기우협록체 matK 기인서렬중건적계통발육관계표명，해신충적학속우보춘거태속차엄의보춘거태속시단계류군.해신충여종관보춘(P ．swinglei )화소화보춘(P ．laxiflora )최위근연，기 matK 기인여후량자분별유5개화11개감기차이，암시저사물충간경력료교장시간적독립연화혹 matK 기인재저사물충중구유교고적감기체환속솔.령외，해신충지생장재단하암석상，이기근연충이급동속대다수기타충류도생장재석회암기질상，암시해신충획득료특수적괄응능력이급여기타근연충간존재생태격리.해신충이급근년래본속허다기타신충류적발현，진일보증가료대해속식물다양성적인식，이급해속식물적연화여다양성분화지미.저사물충소구유적고도구역혹국역특유성화희유성，이급형태상적특수성화유전상적독립성，진일보강화료대해속식물개전보호적중요성.
Primulina (Gesneriaceae)is an enigmatic group of lithophytic plants,which encompass over 160 species malnly distributed in the limestone region of southern China and nothern Vietnam.A majority of species of the genus have very narrow distribution,which have been found in only one or a few proximate localities.It seems that this genus could even possess much more diversity than presently known as lots of new species have recently been and are being discribed,particularly from its distributional center.In the presnt study,a new species of Gesneriaceae,P .bobalensis from Guangxi,China is described and illustrated.We intuitively judged the higher taxonomic unit,i.e.genus,that the as-sumed new species should belong to;compared the morphologies of this assumed new species with all other recognized species previously discribed in the genus and deduced possible close relatives of the new species based on morphological similarity.Then we tested its affinities to other sampled species from the same large region and the divergence of DNA sequences between the assumed new species and its closest relatives.Morphologically,this new species is assumed to be-long to the genus Primulina and can be easily distinguished from all other Gesneriaceae species by its special floral ap-pearance,e.g.lower lip is much longer than upper lip and it has spotted marks on the inside of the upper lip (the majority of other species have striped marks on the inside(s)of the lower and/or upper lips).Subsequently,the taxonomic treat-ment of being attibuted to Primulina and the monophyly of the recircumscribed genus Primulina s.l.are also corrobora-ted by the molecular evidence based on the plastid matK gene.Within the genus the new species is suggested to be the sister of a lineage comprising P .swinglei and P .laxiflora .Further examination of the matK sequences indicated 5 and 11 base differences of P .bobalensis separating from P .swinglei and P .laxiflora ,respectively,implying potential long period of isolation from these species or high substitution rate of the matK gene in these taxa.Moreover,the new species is restricted on Danxia rocks while its closest relatives as well as most of its congeners are confined on limestone rocks, suggesting possible specific edaphic adaptation and isolation of the new species.Further,the high endemism with low a-bundance and usually morphological and molecular distinctiveness of this and many other species of Primulina would al-so superimpose the importance of conservation of these rare species.
