Page 17 - 《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 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