Page 17 - 《广西植物》2022年第10期
P. 17

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 5

     Table 2  Comparison of morphological characters of Selaginella pseudotamariscinaꎬ S. pulvinataꎬ and S. tamariscina

                                                         Species
         Character
                     S. pseudotamariscina        S. pulvinata           S. tamariscina
          Stem       Forming treelike trunk      Not forming treelike trunk  Forming treelike trunk
    Axillary leaf on branch  Lanceateꎬ or ovate ̄lanceateꎬ ca. 2.18 ×  Ovate to triangularꎬ ca. 2.5 × 1  Ovateꎬ ovate ̄triangularꎬ or ellipticꎬ 0.8-
                     0.73 mmꎬ margin lacerate ̄ciliolate  mmꎬ margin lacerate ̄ciliolate  2.6 × 0.4-1.3 mmꎬ margin denticulate
     Dorsal leaf on branch  Symmetricalꎬ lanceateꎬ 2.0- 2.5 × 0.6-  Asymmetricalꎬ obliquely ovate or  Asymmetricalꎬ ellipticꎬ 1.5- 2.5 × 0.3-
                     0. 7 mmꎬ sulcate on upper surfaceꎬ  triangularꎬ 2.8- 3.1 × 0.9- 1.2  0.9 mmꎬ upper surface without sulcateꎬ
                     margin ciliolate or denticulate  mmꎬ  upper  surface  without  margin denticulate ( shortly ciliolate at
                                                 sulcateꎬ margin lacerate  base)
        Ventral leaf  Ovate ̄lanceate  to  ovate ̄triangularꎬ  Oblongꎬ 2. 9 - 3. 2 × 1. 4 - 1. 5  Ovate to triangular or oblong ̄ovateꎬ 1.5-
                     ca. 2.18 × 0.82 mmꎬ shallowly sulcate on  mmꎬ  upper  surface  without  2. 5 × 0. 5 - 1. 2 mmꎬ upper surface
                     upper surfaceꎻ basiscopic margin ciliolate  sulcateꎻ basiscopic margin and  without  sulcateꎻ  basiscopic  margin
                     or denticulateꎻ acroscopic margin lacerate  acroscopic margin lacerate  subentireꎬ serrate or ciliolate ( at base)ꎻ
                     or subentire                                       acroscopic margin lacerate or denticulate
         Strobilus   Slightly dorsiventrally complanate  Tetragonal     Tetragonal
        Sporophyll   Slightly anisophyllousꎻ ventral sporophyll  Isophyllousꎻ ventral and dorsal  Isophyllousꎻ ventral and dorsal sporophyll
                     fertileꎬ dorsal sporophyll sterile  sporophyll both fertile  both fertile


   inference ( BI ) analyses in MrBayes v. 3. 2. 6.  in form and arrangementꎻ dorsal leaves symmetricalꎬ
   (Ronquist et al.ꎬ 2012) under the GTR + G + I     lanceateꎬ and sulcate on upper surfaceꎻ ventral leaves
   model. For each Bayesian analysisꎬ four MCMC chains  shallowly sulcate on upper surface with their basiscopic
   were run simultaneously for 2 million generationsꎬ and  margins ciliolate or denticulateꎻ sporangia borne only on
   sampled every 1 000 generations. The average standard  ventral side of strobilus axes ( Table 2ꎻ Fig. 2ꎻ Fig. 3:
   deviation of split frequencies ( <0.01) was used to  A1ꎬ B1).
   assess the convergence. ML and BI trees and the
   branch support values were visualized using FigTree  4  Taxonomic Treatment
   v.1.4.2 (Rambautꎬ 2014).
                                                         Selaginella pseudotamariscina X. C. Zhang & C.
   3  Results and Discussion                         W. Chenꎬ sp. nov. (Fig. 2).
                                                         Type: VIETNAM. Khanh Hoa Provinceꎬ Orchid
       The ML and BI topologies are totally identicalꎬ and  Islandꎬ on granite rocksꎬ in coastal open forestꎬ 22
   the BI tree is shown in Fig. 1. The results of the  September  2018ꎬ  Cheng ̄Wei  Chen  Wade  5314
   molecular phylogenetic analyses showed that the new  (holotypeꎬ SGN!ꎻ isotypesꎬ PE!ꎬ SING!ꎬ TAIF!).
   species nested within subg. Stachygynandrumꎬ forming  Diagnosis: The new species is similar to S.
   sister relationships with the S. pilifera—S. imbricata clade  tamariscina and S. pulvinata in the rosette ̄forming habitsꎬ
   with weak support ( PP = 0.56/ ML=55). Howeverꎬ of  differs by its slightly anisosporophyllous leaves which are
   species nested in the S. pilifera—S. imbricata cladeꎬ  similar to sterile leaves in form and arrangementꎬ dorsal
   S. pilifera from America is the only rosette ̄forming  leaves symmetricalꎬ lanceateꎬ and sulcate on upper
   species. The S. pilifera—S. pseudotamariscina clade is  surfaceꎬ ventral leaves shallowly sulcate on upper surface
   resolved to be sister to the  S. tamariscina—S.   with their basiscopic margins ciliolate or denticulateꎬ and
   stauntoniana clade with strong support (PP = 1.0/ ML =  only the ventral sporophylls fertile.

   100). Morphologicallyꎬ the new species is similar to  Description: Rosettesꎬ xerophytic. Rhizophores
   S. tamariscina and S. pulvinata. Howeverꎬ the new  restricted to basal portions of stems forming thick
   species differs obviously in several featuresꎬ such as the  massive rootstocksꎻ stems and roots entangled forming
   slightly anisosporophylls which are similar to sterile leaves  treelike trunk. Primary leafy branchlets 2 - 3 pinnately
   12   13   14   15   16   17   18   19   20   21   22