Page 15 - 《广西植物》2022年第10期
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10 期                 张梦华等: 越南莲座状复苏卷柏一新种———越南卷柏(卷柏科)                                       1 6 3 3

       (subg. Stachygynandrum)的一个物种ꎬ与 S. digitata ̄S. imbricata 分支为姐妹群关系ꎮ 该新种与卷柏 ( S.
       tamariscina) 和垫状卷柏 (S. pulvinata) 的形态近似ꎬ其植株均为莲座状ꎬ但不同之处在于中叶对称ꎬ似披针
       形ꎬ上表面具 1 沟槽ꎻ孢子叶穗略压扁ꎻ孢子叶和营养叶性状和排列近似ꎬ孢子叶非同形ꎬ略异形ꎬ正置ꎬ腹面
       孢子叶大于背面孢子叶ꎻ背面孢子叶败育ꎬ孢子囊仅见于腹面孢子叶基部ꎮ
       关键词: 叶绿体基因 rbcLꎬ 复苏植物ꎬ 卷柏属同穗亚属ꎬ 新种ꎬ 分类学




                                                     central coast of Vietnam. It is different from S.
   1  Introduction                                   tamariscina ( P. Beauv.) Spring and S. pulvinata
                                                     ( Hook. & Grev.)    Maxim. by its dorsiventrally
       Selaginella P. Beauv. (1804) is the single genus  complanate strobilus ( vs. tetragonal strobilus ) and
   of Selaginellaceae. It is the largest genus of lycophytesꎬ  symmetrical lanceate dorsal leaves. Historical collections
   containing ca. 700 - 800 speciesꎬ widely distributed  from Vietnam of this species were all identified as
   throughout the worldꎬ with the greatest diversity in the  Selaginella tamariscina ( Alstonꎬ 1951). In order to
   tropics and subtropics ( Jermyꎬ 1990ꎻ Weststrand &  correctly  identify  the  specimen  and  infer  the
   Korallꎬ 2016aꎬ bꎻ Zhang et al.ꎬ 2020 ). Several   phylogenetic position of this unknown speciesꎬ we
   morphology ̄based  classifications  were  proposed  analyzed its sequence of the chloroplast gene rbcL
   (Springꎬ 1840ꎬ 1850ꎻ Bakerꎬ 1883ꎻ Hieronymus &    together with representatives of different subgenera of
   Sadebeckꎬ 1902ꎻ Walton & Alstonꎬ 1938ꎻ Jermyꎬ     Selaginella with special attention to the rosettes
   1986). Based on the most recent molecular phylogenetic  plants. Both morphological and phylogenetic studies
   studiesꎬ seven subgenera were recognized within the  suggested that it represents an undescribed species. We
   Selaginella: subg. Ericetorum Jermyꎬ subg. Exaltatae  therefore described it as a new species named
   Weststrand & Korallꎬ subg. Gymnogynum (P. Beauv.)  Selaginella pseudotamariscina X. C. Zhang & C. W.
   Weststrand & Korallꎬ subg. Lepidophyllae ( Li Bing  Chen and presented the results here.
   Zhang and X. M. Zhou ) Weststrand & Korallꎬ
   subg. Rupestrae Weststrand & Korallꎬ subg. Selaginellaꎬ  2  Materials and Methods
   and subg. Stachygynandrum ( P. Beauv. ex Mirb.)
   Baker (Weststrand & Korallꎬ 2016aꎬ bꎻ Zhang et al.ꎬ  2.1 Morphological assessment
   2020).                                                Morphologies of the newly collected specimens
       Selaginella is morphologically characterized by  were examined and compared to those of Selaginella
   possessing rhizophoresꎬ heterosporyꎬ leaves generally  tamariscina and S. pulvinata using specimens from the
   arranged in  four  decussate  rowsꎬ and  terminal  herbarium of Institute of Botanyꎬ CAS ( PE). Sterile
   strobilus. Species of this genus have various growth  leavesꎬ strobiliꎬ and sporophylls were observed and
   formsꎬ including climbingꎬ creepingꎬ prostrateꎬ erectꎬ  photographed under a Leica S9D stereo microscope.
   suberectꎬ and rosette forms ( Jermyꎬ 1990ꎻ Zhangꎬ  2.2 Molecular analyses
   2004ꎻ Zhang et al.ꎬ 2013 ). Rosettes is a rare        In totalꎬ 32 individuals were sampled to represent
   morphological feature in Selaginella ( occurring in  7 subgenera of Selaginellaꎬ with Isoetes flaccida as the
   ca. 1% species ). Only a few members of subg.     outgroup. Sequences were obtained from the GenBank
   Lepidophyllae and subg. Stachygynandrum are rosettes  except for the new species ( Voucher information and
   which are all resurrection plants (Weststrand & Korallꎬ  GenBank accession numbers are provided in the Table
   2016a).                                           1 ). Phylogenetic reconstruction was based on the
       Recentlyꎬ Mr. Cheng ̄Wei Chen kindly shared us a  chloroplast gene rbcL. We extracted total genomic DNA
   new specimen (Wade 5314) collected from the Southern  from silica gel dried materials using a modified cetyl
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