scholarly journals Phylogenetic relationships of Discyphus scopulariae (Orchidaceae, Cranichideae) inferred from plastid and nuclear DNA sequences: evidence supporting recognition of a new subtribe, Discyphinae

Phytotaxa ◽  
2014 ◽  
Vol 173 (2) ◽  
pp. 127 ◽  
Author(s):  
GERARDO A. SALAZAR ◽  
Cássio Van den Berg ◽  
ALEX POPOVKIN
Keyword(s):  
Maximum Likelihood ◽  
Dna Sequences ◽  
Phylogenetic Relationships ◽  
Maximum Parsimony ◽  
Nuclear Dna ◽  
Floral Morphology ◽  
Systematic Position ◽  
Morphological Differences ◽  
Early Radiation ◽  
Molecular Trees

The monospecific genus Discyphus, previously considered a member of Spiranthinae (Orchidoideae: Cranichideae), displays both vegetative and floral morphological peculiarities that are out of place in that subtribe. These include a single, sessile, cordate leaf that clasps the base of the inflorescence and lies flat on the substrate, petals that are long-decurrent on the column, labellum margins free from sides of the column and a column provided with two separate, cup-shaped stigmatic areas. Because of its morphological uniqueness, the phylogenetic relationships of Discyphus have been considered obscure. In this study, we analyse nucleotide sequences of plastid and nuclear DNA under maximum parsimony and maximum likelihood criteria with the aim of clarifying its systematic position and discussing its peculiar morphology in an explicit phylogenetic context. Our analyses failed to support inclusion of Discyphus in Spiranthinae, signifying instead that this genus represents an additional isolated lineage of “core spiranthids.” The notable morphological disparity among such major lineages, as compared with the short internal branches subtending them in the molecular trees, would support the hypothesis that Discyphus represents a relict from an early radiation that also gave rise to Cranichidinae and Spiranthinae, putatively driven by adaptation to different pollinators given the morphological differences in floral morphology among these taxa.

Systematic status of Campydora Cobb, 1920 (Nematoda: Campydorina)

Nematology ◽  
2003 ◽  
Vol 5 (5) ◽  
pp. 699-711 ◽  
Author(s):  
Peter Mullin ◽  
Timothy Harris ◽  
Thomas Powers
Keyword(s):  
Maximum Likelihood ◽  
Ribosomal Dna ◽  
Dna Sequences ◽  
Maximum Parsimony ◽  
Phylogenetic Analyses ◽  
Small Subunit ◽  
Systematic Position ◽  
Nominal Species ◽  
Competing Hypotheses ◽  
Small Subunit Ribosomal Dna

AbstractThe systematic position of Campydora Cobb, 1920, which possesses many unique morphological features, especially in pharyngeal structure and stomatal armature, has long been a matter of uncertainty with the 'position of the Campydorinae' (containing only Campydora) being questionable. A review of the morphology of C. demonstrans, the only nominal species of Campydora concluded that the species warranted placement as the sole member of a monotypic suborder, Campydorina, in the order Dorylaimida. Others placed Campydorina in the order Enoplida. We conducted phylogenetic analyses, using 18s small subunit ribosomal DNA sequences generated from a number of taxa in the subclasses Enoplia and Dorylaimia, to evaluate these competing hypotheses. Although precise taxonomic placement of the genus Campydora and the identity of its closest living relatives is in need of further investigation, our analyses, under maximum parsimony, distance, and maximum likelihood criteria, unambiguously indicate that Campydora shares a common, more recent, ancestry with genera such as Alaimus, Pontonema, Tripyla and Ironus (Enoplida), rather than with any members of Dorylaimida, Mononchida or Triplonchida.

Phylogenetic relationships in the tribe Alysseae (Brassicaceae) based on nuclear ribosomal ITS DNA sequences

Botany ◽  
2008 ◽  
Vol 86 (4) ◽  
pp. 315-336 ◽  
Author(s):  
Suzanne I. Warwick ◽  
Connie A. Sauder ◽  
Ihsan A. Al-Shehbaz
Keyword(s):  
Maximum Likelihood ◽  
Dna Sequences ◽  
Phylogenetic Relationships ◽  
Maximum Parsimony ◽  
Internal Transcribed Spacer ◽  
Sequence Data ◽  
Its Region ◽  
Morphological Characters ◽  
Data Support ◽  
Its Dna Sequences

Sequence data from the nuclear ribosomal internal transcribed spacer (ITS) region of 85 species (131 accessions) were used to determine the tribal limits, monophyly status, and phylogenetic intra-tribal relationships of genera within the tribe Alysseae (Brassicaceae). Both maximum parsimony and maximum likelihood analyses support the recognition of the tribe Alysseae s. str. (12 genera: Alyssoides , Alyssum , Aurinia , Berteroa , Bornmuellera , Clastopus , Clypeola , Degenia , Fibigia , Galitzkya , Hormathophylla , and Physoptychis ). Six well-supported clades were recognized within the Alysseae clade, including two Alyssum clades (one of which includes Clypeola ), an Alyssoides and allies clade (includes Alyssoides , Bornmuellera , Clastopus , Degenia , Fibigia , Hormathophylla , and Physoptychis ), a Berteroa and allies clade (includes Aurinia , Berteroa , and Galitzkya ), a Bornmuellera clade, and a Hormathophylla clade. Morphological and cytological support for these clades is reviewed. The ITS data support the exclusion of the following taxa from the Alysseae, with appropriate tribal assignment given in parentheses: Alyssum klimesii Al-Shehbaz (Camelineae), Asperuginoides (unresolved), Athysanus (Arabideae), Botschantzevia (Arabideae), Didymophysa (unresolved), Farsetia (Malcolmieae), Lobularia (Malcolmieae), and Ptilotrichum (Arabideae). Farsetia and Lobularia are inferred to be monophyletic, and based on molecular and morphological characters they are assigned to Malcolmieae, a recently described tribe.

A Re-analysis of the phylogeny of the genus Protobothrops (Reptilia: Viperidae), with particular reference to the systematic position of P. xiangchengensis

2006 ◽  
Vol 27 (3) ◽  
pp. 433-439 ◽  
Author(s):  
Peng Guo ◽  
Ermi Zhao ◽  
Yaping Zhang ◽  
Junfeng Pang
Keyword(s):  
Maximum Likelihood ◽  
16S Rrna ◽  
Cytochrome B ◽  
Phylogenetic Relationships ◽  
Maximum Parsimony ◽  
Phylogenetic Analyses ◽  
Mitochondrial Gene ◽  
Systematic Position ◽  
Valid Species ◽  
12S Rrna

AbstractBased on three mitochondrial gene fragments (12S rRNA, 16S rRNA, cytochrome b), the phylogeny of Protobothrops is re-analyzed using Maximum-parsimony (MP), Maximum-likelihood (ML), and Bayesian (BI) approaches. All phylogenetic analyses indicate that all putative Protobothrops species examined formed a monophyletic group; however, the intrageneric relationships are still unresolved. The phylogenetic relationships further confirm that P. xiangchengensis is a valid species distinct from P. mucrosquamatus and that it is closely related to P. jerdonii.

scholarly journals Phylogenetic relationships of Cranichidinae and Prescottiinae (Orchidaceae, Cranichideae) inferred from plastid and nuclear DNA sequences

2009 ◽  
Vol 104 (3) ◽  
pp. 403-416 ◽  
Author(s):  
Gerardo A. Salazar ◽  
Lidia I. Cabrera ◽  
Santiago Madriñán ◽  
Mark W. Chase
Keyword(s):  
Dna Sequences ◽  
Phylogenetic Relationships ◽  
Nuclear Dna

Towards a monophyletic classification of Lejeuneaceae III: the systematic position of Leiolejeunea

Phytotaxa ◽  
2014 ◽  
Vol 170 (3) ◽  
pp. 187 ◽  
Author(s):  
ALFONS SCHÄFER-VERWIMP ◽  
KATHRIN FELDBERG ◽  
SHANSHAN DONG ◽  
HUUB VAN MELICK ◽  
DENILSON F. PERALTA ◽  
...  
Keyword(s):  
Bayesian Inference ◽  
Maximum Likelihood ◽  
Dna Sequences ◽  
Its Region ◽  
Systematic Position ◽  
Leaf Cell ◽  
Oil Bodies ◽  
Sister Relationship ◽  
First Time

The derived liverwort Leiolejeunea grandiflora was recollected at the type locality in Jamaica after more than 100 years. The characteristics of its oil bodies were described for the first time based on the new collections. Each leaf cell possesses 2-4(-6) rather small, subhomogeneous to very finely segmented, subglobose to ellipsoidal, colorless oil bodies. The plants were either dioicous or autoicous. DNA sequences of two chloroplast regions (trnL-trnF, rbcL) and the nuclear ribosomal ITS region were obtained for two accessions of Leiolejeunea to enable the inference of the phylogenetic relationships of these plants. Based on Bayesian inference of phylogeny as well as maximum parsimony and maximum likelihood analyses of a dataset including 87 representatives of Lejeuneaceae, Leiolejeunea was found as the putative sister to either Echinolejeuneinae or Cheilolejeuneinae. Thus, we propose the new monogeneric subtribe Leiolejeuneinae with relationships to Cheilolejeuneinae and Echinolejeuneinae. The analyses included also one accession of the generitype of Cheilolejeunea, C. decidua [= Cheilolejeunea adnata]. This species was found in a well supported sister relationship with Cystolejeunea. To avoid nomenclatural confusion, we propose a wide genus concept for Cheilolejeunea including Aureolejeunea, Cyrtolejeunea, Cystolejeunea, Evansiolejeunea, Leucolejeunea, and Omphalanthus.

The phylogenetic relationships of Paramesotriton (Caudata: Salamandridae) based on partial mitochondrial DNA gene sequences

Zootaxa ◽  
2012 ◽  
Vol 3150 (1) ◽  
pp. 59
Author(s):  
XIAOMING GU ◽  
HUI WANG ◽  
RONGRONG CHEN ◽  
YINGZHOU TIAN ◽  
SONG LI
Keyword(s):  
Mitochondrial Dna ◽  
Bayesian Inference ◽  
Maximum Likelihood ◽  
16S Rdna ◽  
Phylogenetic Relationships ◽  
Maximum Parsimony ◽  
Mitochondrial Gene ◽  
Sister Group ◽  
Species Group ◽  
Close Phylogenetic Relationship

We examined phylogenetic relationships among newst of the genus Paramesotriton using partial mitochondrial gene se-quences, including the ND2-tRNATyr region (1415 bp) and the 12S rDNA-tRNAVal -16S rDNA region (1774 bp), from 42individuals of 10 recognized Paramesotriton species and outgroups by Bayesian inference (BI), Maximum likelihood(ML) and Maximum Parsimony (MP) methods. We found that, (1) Laotriton laoensis is the sister group of Paramesotri-ton, (2) the genus Paramesotriton is monophyletic, composed of either the P. caudopunctatus species group and the P.chinensis species group, or the subgenera Allomesotriton and Paramesotriton (3) P. longliensis and P. zhijinensis shouldbe placed in the P. caudopunctatus species group or subgenus Allomesotriton; (4) P. fuzhongensis is not a junior synonym of P. chinensis, and there is a close phylogenetic relationship between P. fuzhongensis and P. guangxiensis.

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