Corresponding author: Rolando Tenoch Bárcenas Luna (
Academic editor: A. Calvente
Molecular phylogenetic studies of the six currently accepted species in the genus
Vargas-Luna MD, Hernández-Ledesma P, Majure LC, Puente-Martínez R, Macías HMH, Luna RTB (2018) Splitting
Current taxonomic delimitation of
The earlier restriction site variation study of
Most molecular systematic studies that have included species of
In this study, the phylogenetic relationships of all species and subspecies of
A total of 26 taxa, including all six currently accepted species of
Total genomic DNA was extracted from silica gel dried stem tissues or from herbarium samples. Approximately 20 to 30 mg of tissue was ground, from which DNA was extracted with a CTAB 2% protocol described in
A set of 42 morphological characters were coded (Appendix 2) by observations during field work and by examination of herbarium specimens generated in this study and specimens already deposited in herbaria (ASU, DES, MEXU and QMEX). Primary homology statements (
In order to generate consensus sequences, both forward and reverse sequences were assembled manually in PHYDE (
Consensus sequences were automatically aligned with MUSCLE (
For each individual dataset and for the cpDNA concatenated matrix, maximum parsimony (
To identify putative synapomorphies and homoplasies for each of the recovered clades, an unambiguous character optimisation on an
In this study, 34 new sequences from the a tpB-
Summary statistics of the datasets analyzed.
Total length (nucleotides) | Informative characters | Terminals | Taxa | |
---|---|---|---|---|
|
913 | 76 (8.3%) | 48 | 28 |
|
319 | 48 (15.04%) | 47 | 24 |
|
1082 | 62 (5.7%) | 48 | 21 |
|
1292 | 43 (3.3%) | 30 | 24 |
|
333 | 73 (22%) | 23 | 16 |
|
610 | 231 (38%) | 37 | 21 |
|
1855 | 103 (5.5%) | 35 | 26 |
|
1910 | 134 (7.0%) | 26 | 26 |
|
2847 | 207 (7.3%) | 26 | 26 |
Phylogenetic relationship of
Phylogenetic relationships of
Phylogenetic relationship of
Bayesian 50% majority rule consensus tree showing phylogenetic relationship of
The cpDNA plus morphology and the total evidence analyses recovered
All concatenated analyses recovered three major clades within the HEA clade. One clade included the clade of
The phylogenetic signal of
Although the unambiguous optimisation of characters could not detect any synapomorphic characters for the
So far,
Within the
The only synapomorphic character detected by the unambiguous optimisation analysis for the
The surprisingly closer phylogenetic relationship of
Interestingly, the phylogenetic analyses here conducted recovered with medium to high support an infraspecific structure for the two widely distributed species of
This is the first phylogenetic study that has evaluated and combined molecular data from chloroplast and nuclear genomes with morphology to test the monophyly of all species and subspecies of
[Mexico], near Lake Santa Maria, Chihuahua, a bunch of spines collected by Dr. Parryi, s/n, apparently lost (
U.S.A., California, Mohave Valley, Bigelow s/n., 8 Mar 1854 (
U.S.A., Arizona, near the Rio Colorado, Siler s/n., Nov., 1881 (
1 | Stem epidermis glabrous; ovoid to almost circular seeds; campilotropous or anatropous embryos and rounded or acute cotyledons |
|
– | Stem epidermis pubescent; navicular seeds; orthotropous embryos and obtuse cotyledons |
|
2 | Stem apex with scarce trichomes; acute ribs; slightly tubular flowers; campilotropous embryos and acute cotyledons |
|
– | Stem apex with a dense cover of trichomes; obtuse ribs; campanulate flowers, anatropous embryos and rounded cotyledons |
|
1 | Areoles in mature plants with conspicuous spines |
|
– | Areoles in mature plants with inconspicuous spines |
|
2 | Stiff straight spines and completely yellow flowers |
|
– | Fexible curved spines and yellow flowers with a reddish base |
|
3 | Stems ribbed |
|
– | Stems tuberculated |
|
4 | Stems globose to cylindrical, commonly with five acute ribs |
|
– | Stems depressed, commonly with eight obtuse ribs |
|
1 | Stems rarely to frequently caespitose; yellow flowers and dry fruits |
|
– | Stems Simple; pink flowers and juicy fruits |
|
2 | Stems rarely caespitose; yellow flowers with a clear reddish base |
|
– | Stems commonly caespitose, forming large clumps; yellow flowers without a reddish base |
|
3 | Spine epidermis and pericarpel scales pubescent; testa cells with periclinal walls with convex relief (papillated) |
|
– | Spine epidermis and pericarpel scales glabrous; testa cells with periclinal walls with inconspicuous relief (flat) |
|
1 | Mature plants with stems large globose to barrel shaped with up to 60 ribs; yellow flowers; testa cells with inconspicuous relief |
|
– | Mature plants with stems depressed, globose to rarely short cylindrical frequently with eight ribs; pink to crimson flowers, seeds with testa cells with a convex relief |
|
2 | Seedlings with 1 to 2 spines per areole; mature plants with frequently depressed stems; straight spines and light pink flowers |
|
– | Seedlings commonly with 4 spines per areole; mature plants frequently with short cylindrical stems; curved spines and pink to crimson flowers |
|
MVL would like to thank Francisco Félix for field work assistance, to the Consejo Nacional de Ciencia y Tecnología (CONACyT) for a graduate scholarship to develop doctoral studies at the Facultad de Ciencias Naturales of the Universidad Autónoma de Querétaro (UAQ). MVL thanks UAQ for a research fellowship to develop laboratory and fieldwork at the Desert Botanical Garden. MVL and RTB would like to thank Secretaría de Medio Ambiente y Recursos Naturales for granting the collection permit (SEMARNAT 00140/15) to produce herbarium materials of the Mexican populations. We also thank the Arizona Bureau of Land Management for permits to the Desert Botanical Garden used in this work. All authors thank the personnel and curators of ASU, DES, MEXU and QMEX. RTB, MVL and PHL would like to thank the International Organization for Succulent Plant Studies (IOS) for partial financial support for this project during the development of the project of betalain related pigments in
1.1 Scientific names, voucher information and Genbank accession numbers for
1.2 Scientific names, voucher information and Genbank accession numbers for the
Morphological characters, character states, and development stages at which the characters were coded.
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A | |
B | |
B | |
C | |
C | |
C | |
C | |
E | |
E | |
E | |
E | |
D, E | |
E | |
E | |
E | |
F | |
F | |
F | |
F | |
F | |
F | |
F | |
F | |
F | |
F | |
F | |
F | |
G | |
G | |
G | |
G | |
G | |
G | |
H | |
H | |
H | |
H | |
H | |
H | |
H | |
H | |
– | |
– | |
– | |
– | |
– | |
– | |
– | |
– | |
– | |
– | |
– | |
– | |
– |