Molecular systematics of subtribe Banksiinae (Banksia and Dryandra; Proteaceae) Based on cpDNA and nrDNA sequence data: Implications for taxonomy and biogeography

1998 ◽  
Vol 11 (4) ◽  
pp. 321 ◽  
Author(s):  
Austin R. Mast

Despite considerable research interest in the subtribe Banksiinae (Banksia L.f. and Dryandra R.Br.), no strongly supported phylogenetic hypothesis for the relationship between the genera exists, nor have molecular characters been sampled for phylogenetic reconstruction at any level. In this study, DNA sequence characters were sampled from chloroplast DNA (cpDNA; the trnL intron, the trnL 3′ exon, and the spacer between the trnL 3′ exon and trnF) and nuclear ribosomal DNA (nrDNA; both internal transcribed spacers) of 18 species of Banksia and five of Dryandra, with six outgroup taxa from the subfamily Grevilleoideae. The molecular characters provided the opportunity to code taxa outside of Banksia for cladistic comparison with the genus—an opportunity not previously provided by morphological characters. Cladistic analyses, using parsimony, explored the effects of various weightings of transition to transversion events and base substitution to insertion and deletion events to determine which relationships in the cladograms were robust. The trnL/trnF and ITS characters strongly supported a paraphyletic Banksia with respect to a monophyletic Dryandra. The molecular results supported a single root for Thiele and Ladiges’(1996) unrooted morphological cladogram along the branch between the Isotylis to B. fuscolutea clade and the Grandes to B. tricuspis clade. George’s (1981) subgenus Banksia and section Banksia appeared dramatically non-monophyletic. The distribution of eastern taxa at derived positions on the molecular cladograms suggested considerable cladogenesis in the the genus prior to the formation of the Nullarbor Plain during the Tertiary.

Horticulturae ◽  
2020 ◽  
Vol 6 (1) ◽  
pp. 19
Author(s):  
Patricia Coughlan ◽  
James C. Carolan ◽  
Ingrid L. I. Hook ◽  
Lisa Kilmartin ◽  
Trevor R. Hodkinson

Taxus is a genus of trees and shrubs with high value in horticulture and medicine as a source of the anticancer drug paclitaxel. The taxonomy of the group is complex due to the lack of diagnostic morphological characters and the high degree of similarity among species. Taxus has a wide global geographic distribution and some taxonomists recognize only a single species with geographically defined subgroups, whereas others have described several species. To address these differences in taxonomic circumscription, phylogenetic analyses were conducted on DNA sequences using Maximum Likelihood, Bayesian Inference and TCS haplotype networks on single and combined gene regions obtained for the nuclear ribosomal ITS region and the plastid trnL intron and trnL-F intergenic spacer. Evidence is presented for the sister group status of Pseudotaxus to Taxus and the inclusion of Amentotaxus, Austrotaxus, Cephalotaxus and Torreya within Taxaceae. Results are consistent with the taxonomic recognition of nine species: T. baccata, T. brevifolia, T. canadensis, T. cuspidata, T. floridana, T. fuana, T. globosa, T. sumatrana and T. wallichiana, but evidence is found for less species distinction and considerable reticulation within the T. baccata, T. canadensis and T. cuspidata group. We compare the results to known taxonomy, biogeography, present new leaf anatomical data and discuss the origins of the hybrids T. ×media and T. ×hunnewelliana.


2000 ◽  
Vol 23 (4) ◽  
pp. 931-940 ◽  
Author(s):  
Antonio Salatino ◽  
Maria Luiza Faria Salatino ◽  
Déborah Yara A.C. dos Santos ◽  
Márcia Cristina B. Patrício

Hypotheses are presented on the evolution of structural patterns of secondary metabolites (flavonoids and foliar wax alkanes) and fatty acids of families of "campos rupestres". The distribution of fatty acids is given for genera of Lythraceae, with emphasis on Cuphea (supposedly more advanced) and Diplusodon. Compounds with saturated short chains represent a derived condition in Lythraceae although they are probably restricted to Cuphea. It is suggested that evolution selected for more complex flavonoid patterns in Cuphea, with the inclusion of C-glycoflavones and methoxylated flavonols (rhamnetin and isorhamnetin), which are not found in members of Diplusodon and Lafoensia. The supposedly primitive groups of Eriocaulaceae (e.g., Paepalanthus) presented more complex flavonoid patterns characterized by flavones and flavonols, the latter frequently being 6-hydroxylated or methoxylated. More advanced groups of Eriocaulaceae (e.g., Leiothrix and Syngonanthus) apparently possess only flavones, C-glycoflavones are a salient feature of species with smaller habits. In Velloziaceae, members of the primitive subfamily Vellozioideae show distribution of alkanes of foliar epicuticular wax in which C27, C29 or C31 predominate; members of the derived subfamily Barbacenioideae usually show distributions with a predominance of C33 or C35, while species of Pleurostima (Barbacenioideae) have C31 as the main homologue, thus being intermediate between the two subfamilies. It is suggested that the evolution of alkanes in Velloziaceae follows a trend toward elongation of carbon chains. The condition of advanced or primitive chemical patterns is inferred from the results of cladistic analyses based on morphological characters (Eriocaulaceae and Lythraceae), and morphological and molecular characters (Velloziaceae).


2011 ◽  
Vol 43 (6) ◽  
pp. 617-638 ◽  
Author(s):  
Leena MYLLYS ◽  
Saara VELMALA ◽  
Håkon HOLIEN ◽  
Pekka HALONEN ◽  
Li-Song WANG ◽  
...  

AbstractThe phylogenetic relationships of the genus Bryoria were examined using ITS, partial glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and mitochondrial SSU rDNA sequence data in addition to 20 chemical and morphological characters. This first comprehensive molecular study to assess Bryoria phylogeny includes representatives from all the traditionally recognized four sections. Combined cladistic analyses of 88 Bryoria specimens representing at least 25 species resulted in highly resolved phylogenies. Based on the results, a new infrageneric classification for the genus is proposed. Five sections are recognized, largely corresponding to the existing classification, with the addition of section Americanae. The study shows that while most species with an erect growth-form are clearly monophyletic, current species status of many pendent taxa can be questioned.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Tanapan Sukee ◽  
Ian Beveridge ◽  
Anson V. Koehler ◽  
Ross Hall ◽  
Robin B. Gasser ◽  
...  

Abstract Background The subfamily Phascolostrongylinae (Superfamily Strongyloidea) comprises nematodes that are parasitic in the gastrointestinal tracts of macropodid (Family Macropodidae) and vombatid (Family Vombatidae) marsupials. Currently, nine genera and 20 species have been attributed to the subfamily Phascolostrongylinae. Previous studies using sequence data sets for the internal transcribed spacers (ITS) of nuclear ribosomal DNA showed conflicting topologies between the Phascolostrongylinae and related subfamilies. Therefore, the aim of this study was to validate the phylogenetic relationships within the Phascolostrongylinae and its relationship with the families Chabertiidae and Strongylidae using mitochondrial amino acid sequences. Methods The sequences of all 12 mitochondrial protein-coding genes were obtained by next-generation sequencing of individual adult nematodes (n = 8) representing members of the Phascolostrongylinae. These sequences were conceptually translated and the phylogenetic relationships within the Phascolostrongylinae and its relationship with the families Chabertiidae and Strongylidae were inferred from aligned, concatenated amino acid sequence data sets. Results Within the Phascolostrongylinae, the wombat-specific genera grouped separately from the genera occurring in macropods. Two of the phascolostrongyline tribes were monophyletic, including Phascolostrongylinea and Hypodontinea, whereas the tribe Macropostrongyloidinea was paraphyletic. The tribe Phascolostrongylinea occurring in wombats was closely related to Oesophagostomum spp., also from the family Chabertiidae, which formed a sister relationship with the Phascolostrongylinae. Conclusion The current phylogenetic relationship within the subfamily Phascolostrongylinae supports findings from a previous study based on ITS sequence data. This study contributes also to the understanding of the phylogenetic position of the subfamily Phascolostrongylinae within the Chabertiidae. Future studies investigating the relationships between the Phascolostrongylinae and Cloacininae from macropodid marsupials may advance our knowledge of the phylogeny of strongyloid nematodes in marsupials. Graphical Abstract


2019 ◽  
Vol 151 (6) ◽  
pp. 696-716 ◽  
Author(s):  
Christine Jewel C. Uy ◽  
Ji Hyoun Kang ◽  
John C. Morse ◽  
Yeon Jae Bae

AbstractThe phylogenetic relationships among the members of Macronematinae (Trichoptera: Hydropsychidae) have long been debated and often revised. Our study based on a large subunit (28S) nuclear ribosomal DNA (D2 expansion fragment; 464 base pairs) of gene sequences found all genera to be monophyletic except for the genus Polymorphanisus Walker, which produced two clades in accordance with its species groups established using morphological characters. Phylogenetic reconstruction based on mitochondrial cytochrome oxidase I (658 base pairs) found the same monophyletic relationships, however, except for the genera Polymorphanisus and Macrostemum Kolenati. The placement of the genus Leptonema Guérin-Méneville as the basal clade in the subfamily was also ruled out, which is consistent with previous morphological findings. The monophyly of two previously recognised tribes (Macronematini and Polymorphanisini) was not supported. We also found that the genera Centromacronema Ulmer, Baliomorpha Neboiss, and Macronema Pictet are most closely related, having three head setal warts on the vertex of the head and unsegmented inferior appendages of male genitalia as their synapomorphies. Our study supported the hypothesis of close relationship of the genera Amphipsyche McLachlan and Protomacronema Ulmer with the morphological synapomorphies: absence of a forewing discoidal cell and the presence of elevated head carinae on the larvae. Some notable evolutionary novelties in the structure of adults in various lineages of this subfamily include reduction of maxillae and labium, reduction and loss of a discoidal cell and evolution of a c-sc crossvein in each forewing, fusion of segments in each male inferior appendage, and evolution of dark colour patterns in the forewings. Also, the head setal warts, which are unique organs in Trichoptera, evolved towards a decreasing number in the subfamily. This first molecular phylogenetic study, covering most genera in Macronematinae and including an interpretation of 12 key evolutionary novelties, provides an important basis for resolving long-standing questions regarding phylogenetic relationships and classification of genera and species and helps lay a stronger foundation for inference of testable hypotheses about functional traits for species of this common and widespread subfamily.


2009 ◽  
Vol 57 (1) ◽  
pp. 1 ◽  
Author(s):  
Neil B. Chilton ◽  
Florence Huby-Chilton ◽  
Peter M. Johnson ◽  
Ian Beveridge ◽  
Robin B. Gasser

Four morphospecies of Cloacina, parasitic nematodes in the stomachs of rock wallabies (Petrogale spp.) from Queensland, were compared genetically using sequence data of the two internal transcribed spacers of nuclear ribosomal DNA (rDNA). The results suggest that two geographically isolated populations of C. ernabella from P. purpureicollis were genetically distinct. Based on the autapomorphic species concept, these two C. ernabella populations represented different species. For the three other nematode morphospecies, there were genetic differences among individuals of a morphospecies present in different species of host. The results suggest that each may represent a complex of sibling species, with a different species present in each species of rock wallaby examined for that morphospecies. In the C. caenis and C. pearsoni complexes, the lineage present in P. purpureicollis from western Queensland represents a sister taxon to those in the P. pencillata complex from the east coast. In the C. robertsi complex, the taxon parasitic in P. persephone represents the sister taxon to those in the P. pencillata complex and in P. purpureicollis. C. robertsi was found for the first time in P. purpureicollis from Winton in central Queensland, suggesting contact in the recent past between populations of P. purpureicollis and a member of the P. penicillata complex.


2015 ◽  
Vol 22 (2) ◽  
pp. 111-118 ◽  
Author(s):  
Fahad M.A. Al-Hemaid ◽  
M. Ajmal Ali ◽  
Joongku Lee ◽  
Soo-Yong Kim ◽  
Md. Oliur Rahman

The present study explored molecular phylogenetic analysis of 28 species of Euphorbia L. for the identification and establishment of molecular evolutionary relationships of Euphorbia scordifolia Jacq. within the genus based on the internal transcribed spacers (ITS) sequences (ITS1-5.8S-ITS2) of nuclear ribosomal DNA (nrDNA). The sequence similarity search using Basic Local Alignment Search Tool (BLAST) of the ITS sequence of E. scordifolia showed the closest sequence similarity to E. supina Raf. The analysis of ITS sequence data revealed four major clades consistent with subgeneric classifications of the genus. Molecular data support placement of E. scordifolia in the subgenus Chamaesyce.Bangladesh J. Plant Taxon. 22(2): 111-118, 2015 (December)


Author(s):  
Anna Wróbel ◽  
Ewelina Klichowska ◽  
Evgenii Baiakhmetov ◽  
Arkadiusz Nowak ◽  
Marcin Nobis

AbstractThe Eragrostis pilosa complex (Poaceae) comprises five widely distributed and regionally invasive species—E. albensis, E. amurensis, E. imberbis, E. multicaulis, and E. pilosa, distinguished by tiny and variable morphological characters and with so far unknown phylogenetic relationships. Recently, some doubts have been raised about the status of an invasive glandular morphotype occurring in Central Europe assigned either to E. amurensis or to E. albensis. Here, we addressed this issue by analysing morphology, internal transcribed spacers of nuclear ribosomal DNA, and five inter-simple sequence repeat markers. The genetic evidence supported closer relationship of this glandular morphotype to eglandular E. albensis, widely established in Central Europe, than to glandular E. amurensis described from Asia. We propose to adopt a new taxonomic treatment that E. albensis includes both eglandular and glandular individuals, and to classify the glandular ones as E. albensis var. scholziana M. Nobis & A. Wróbel var. nova. Currently this new taxon is known from a dozen of localities in Central Europe and is invasive in the lower section of the Oder River valley, whereas Eragrostis albensis var. albensis has already spread widely across Europe in riparian phytocenoses and anthropogenic habitats. Since probably the first registered records in 1940s, it has been observed in European part of Russia, Belarus, Ukraine, Poland, Slovakia, Czech Republic, Germany, Austria, the Netherlands, and its further invasion is likely to proceed. We provided distribution maps concerning spread dynamics of E. albensis in Europe from 1947 to 2020. In total, the species has been observed on over 1300 localities so far, most of which were found after 2000.


2021 ◽  
Author(s):  
Takehiro K Katoh ◽  
Ji-Min Chen ◽  
Jin-Hua Yang ◽  
Guang Zhang ◽  
Lu Wang ◽  
...  

The genus Dichaetophora Duda is of 69 formally described, Old World species assigned into five species groups, i.e., agbo, tenuicauda, acutissima, sinensis and trilobita. Most of these species were delimitated morphologically, with the within-genus relationship established largely via cladistic analyses of morphological characters. In the present study, we first conducted species-delimitation with aids of morphological data as well DNA barcodes (nucleotide sequences of the mitochondrial COI, i.e., cytochrome c oxidase subunit I, gene), for a huge sample of Dichaetophora and allied taxa (genus Mulgravea and subgenus Dudaica of Drosophila) collected from a wide geographical range. Then, multiple-locus phylogenetic reconstruction was conducted based on elaborate taxon sampling from the known and newly recognized species in the above taxa, with the maximum likelihood (ML) and Bayesian inference (BI) methods. As a result, 189 species (186 of Dichaetophora, 2 of Mulgravea, and 1 for Dudaica) were newly recognized. In our ML and BI trees, several well-supported species clusters equivalent to the species groups agbo (excluding of neocirricauda), tenuicauda, sinensis (inclusive of neocirricauda) and trilobita of Dichaetophora, were recovered, with the sister-relationship between the third and fourth proved. Other well-supported clusters include 1) a clade comprising of Di. acutissima group and Dudaica, with the former proved to be paraphyletic to the latter; 2) genus Mulgravea; 3) a clade comprising exclusively of newly recognized Dichaetophora species, and was placed as sister to Mulgravea. Three of the remaining five representatives of Dichaetophora species form a solid cluster, leaving the positions of the last two unresolved. The present study greatly renewed out knowledge about the species diversity in a pan-Dichaetophora clade, providing us with an unprecedented historical framework for further taxonomy revision of this clade, and valuable baseline knowledge for future reconstruction of the history of its adaptive diversification in the particular microhabitats.


2002 ◽  
Vol 80 (9) ◽  
pp. 1002-1017 ◽  
Author(s):  
Suzanne I Warwick ◽  
Ihsan A Al-Shehbaz ◽  
Robert A Price ◽  
Connie Sauder

The genus Sisymbrium as currently circumscribed includes about 94 species disjunctly distributed in the Old (41 spp.) and the New World (53 spp.). Sisymbrium has been variously delimited, with several segregate genera proposed (subtribe Sisymbriinae) primarily for the new World taxa, including Schoenocrambe, Coelophragmus, and Mostacillastrum. Using sequence data from the internal transcribed spacers of nuclear ribosomal DNA and the 5.8S rRNA gene (collectively, ITS region), we examined the evolutionary relationships of Old and New World Sisymbrium species with its segregate genera and the validity of O.E. Schulz's classical sectional treatment of Sisymbrium. Sequence data were obtained from 33 Sisymbrium species, representing all 14 sections and two Sisymbrium species formerly assigned to segregate genera Coelophragmus and Mostacillastrum (subtribe Sisymbriinae), and two putative Sisymbrium species currently assigned to Neotorularia. Sequence data were also obtained from 26 taxa from segregate or related genera includingSchoenocrambe, Werdermannia (subtribe Sisymbriinae), eight genera in the Thelypodieae, Sibara (tribe Arabideae) and Pringlea (tribe Pringleeae), four members of the tribe Brassiceae, and three other Neotorularia species. Results from maximum parsimony analysis showed a polyphyletic origin for Sisymbrium and did not correspond well to Schulz's sectional classification. Sisymbrium species were split into three major clades: Old World Sisymbrium (including Neotorularia aculeolata, Neotorularia afghanica, and the type species of Schoenocrambe, Schoenocrambe linifolia, the sole New World member of this Old World clade); New World Sisymbrium (along with the remaining New World taxa) and designated as the New World Thelypodieae alliance; and the tribe Brassiceae ( including Sisymbrium supinum and Sisymbrium thellungii).Key words: Sisymbrium, Schoenocrambe, ITS, Thelypodieae, taxonomy, Brassicaceae.


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