Character analysis, phylogeny, and classification of the moss genus Pohlia

1984 ◽  
Vol 62 (2) ◽  
pp. 219-229 ◽  
Author(s):  
Jonathan Shaw

Forty-one Pohlia taxa coded for their expression of 36 qualitative morphological characters are analyzed using cladistic and phenetic methods. Phenetic approaches include similarity graph clustering and divisive methods utilizing information theoretic criteria. The Wagner Tree parsimony method and character compatibility analysis provide estimates of cladistic relationships. Four major lineages within the genus differ primarily in sporophyte characters, with specific differences based largely on gametophytic features. Peristome simplification may have occurred several times within Pohlia. An infrageneric classification is proposed with diagnostic descriptions and nomenclature provided.

1983 ◽  
Vol 61 (2) ◽  
pp. 518-535 ◽  
Author(s):  
Bernard R. Baum

A phylogenetic analysis of Triticeae was performed by means of numerical methods. Five methods, each based on extreme assumptions of parameters so interpreted under Felsenstein's (1979) evolutionary model, were used: Camin–Sokal parsimony, Wagner parsimony, Dollo parsimony, polymorphism parsimony, and character-compatibility analysis. Although a considerable amount of parallelism was, for some time, suspected to have occurred in Triticeae (by Stebbins for instance) so that for this reason perhaps the assumptions of polymorphism parsimony might be most suitable for phylogenetic analysis, the five methods were used because the evolutionary assumptions for each investigated character are, and probably will long remain, unknown.Data input consisted of sets of hypothesized transformation series, each set subjected to analyses using the five methods. Results of an analysis provided the basis for altering the set of hypothesized transformation series for subsequent analysis. Analyses were carried out repeatedly until stabilization; that is until, in the author's judgment, the most parsimonious solution was arrived at and further trials were of diminishing return. The most parsimonious tree obtained served as a base for subsequent elaboration of the final tree, taking into consideration genetic information primarily, and for the erection of the proposed phylogenetic classification of Triticeae. A key is provided for identification of the groupings in the tribe. The proposed classification is discussed in the light of previous classifications, even though none of them were phylogenetic in the sense of Hennig.


2017 ◽  
Author(s):  
Thomas Denk ◽  
Guido W. Grimm ◽  
Paul S. Manos ◽  
Min Deng ◽  
Andrew Hipp

In this paper, we review major classification schemes proposed for oaks by John Claudius Loudon, Anders Sandøe Ørsted, William Trelease, Otto Karl Anton Schwarz, Aimée Antoinette Camus, Yuri Leonárdovich Menitsky, and Kevin C. Nixon. Classifications of oaks (Fig. 1) have thus far been based entirely on morphological characters. They differed profoundly from each other because each taxonomist gave a different weight to distinguishing characters; often characters that are homoplastic in oaks. With the advent of molecular phylogenetics our view has considerably changed. One of the most profound changes has been the realisation that the traditional split between the East Asian subtropical to tropical subgenus Cyclobalanopsis and the subgenus Quercus that includes all other oaks is artificial. The traditional concept has been replaced by that of two major clades, each comprising three infrageneric groups: a Palearctic-Indomalayan clade including Group Ilex (Ilex oaks), Group Cerris (Cerris oaks) and Group Cyclobalanopsis (cycle-cup oaks), and a predominantly Nearctic clade including Group Protobalanus (intermediate or golden cup oaks), Group Lobatae (red oaks) and Group Quercus (white oaks, with most species in America and some 30 species in Eurasia). The main morphological feature characterising these phylogenetic lineages is pollen morphology, a character overlooked in traditional classifications. This realisation, along with the now available (molecular-)phylogenetic framework, opens new avenues for biogeographic, ecological and evolutionary studies and a re-appraisal of the fossil record. We provide an overview about recent advances in these fields and outline how the results of these studies contribute to the establishment of a unifying systematic scheme of oaks. Ultimately, we propose an updated classification of Quercus recognising two subgenera with eight sections. This classification considers morphological traits, molecular-phylogenetic relationships, and the evolutionary history of one of the most important temperate woody plant genera.


2009 ◽  
Vol 22 (5) ◽  
pp. 384 ◽  
Author(s):  
Carlos Parra-O. ◽  
Michael J. Bayly ◽  
Andrew Drinnan ◽  
Frank Udovicic ◽  
Pauline Ladiges

Phylogenetic relationships of sections and species within Corymbia (Myrtaceae), the bloodwood eucalypts, were evaluated by using combined analyses of nuclear rDNA (ETS + ITS) and morphological characters. Combining morphological characters with molecular data provided resolution of relationships within Corymbia. The analyses supported the monophyly of the genus and recognition of the following two major clades, treated here as new subgenera: subgenus Corymbia, including informal sections recognised by Hill and Johnson (1995), namely Rufaria (red bloodwoods), Apteria and Fundoria; and subgenus Blakella, including sections Politaria (spotted gums), Cadagaria, Blakearia (paper-fruited bloodwoods or ghost gums) and Ochraria (yellow bloodwoods). Hill and Johnson’s section Rufaria is monophyletic if Apteria and Fundoria are included. It is evident that, among the red bloodwoods, series are not monophyletic and several morphological characters result from convergent evolution. There was strong morphological and molecular evidence that the three species of red bloodwoods that occur in south-western Western Australia (series Gummiferae: C. calophylla and C. haematoxylon, and series Ficifoliae: C. ficifolia) form a monophyletic group, separate from the eastern C. gummifera (series Gummiferae), which is probably sister to the clade of all other red bloodwoods. Phylogenetic results supported recognition of new taxonomic categories within Corymbia, and these are formalised here.


2010 ◽  
Vol 23 (2) ◽  
Author(s):  
Carlos Parra-O. ◽  
Michael J. Bayly ◽  
Andrew Drinnan ◽  
Frank Udovicic ◽  
Pauline Ladiges

Phylogenetic relationships of sections and species within Corymbia (Myrtaceae), the bloodwood eucalypts, were evaluated by using combined analyses of nuclear rDNA (ETS + ITS) and morphological characters. Combining morphological characters with molecular data provided resolution of relationships within Corymbia. The analyses supported the monophyly of the genus and recognition of the following two major clades, treated here as new subgenera: subgenus Corymbia, including informal sections recognised by Hill and Johnson (1995), namely Rufaria (red bloodwoods), Apteria and Fundoria; and subgenus Blakella, including sections Politaria (spotted gums), Cadagaria, Blakearia (paper-fruited bloodwoods or ghost gums) and Ochraria (yellow bloodwoods). Hill and Johnson's section Rufaria is monophyletic if Apteria and Fundoria are included. It is evident that, among the red bloodwoods, series are not monophyletic and several morphological characters result from convergent evolution. There was strong morphological and molecular evidence that the three species of red bloodwoods that occur in south-western Western Australia (series Gummiferae: C. calophylla and C. haematoxylon, and series Ficifoliae: C. ficifolia) form a monophyletic group, separate from the eastern C. gummifera (series Gummiferae), which is probably sister to the clade of all other red bloodwoods. Phylogenetic results supported recognition of new taxonomic categories within Corymbia, and these are formalised here.


2014 ◽  
Vol 59 (1) ◽  
pp. 31-36 ◽  
Author(s):  
Gaik Ee Lee ◽  
Ahmad Damanhuri ◽  
Abdul Latiff ◽  
S. Robbert Gradstein

Abstract The infrageneric classification of the large genus Lejeunea Lib. is poorly understood due to the lack of stable morphological characters characterizing supraspecific groups. Phenetic analysis of 26 morphological features of 31 Asian Lejeunea species separated two main species clusters based on the number of superior central cells at underleaf bases. The number of superior central cells had not previously been utilized in the classification of Lejeunea and appears to be new and stable morphological feature within this genus. The presence of surface wax was confirmed in L. flava (Sw.) Nees and was newly recorded in L. mimula Hürl. and L. tuberculosa Steph. We suggest that wax ornamentation may be a useful taxonomic feature at species level in Lejeunea.


2020 ◽  
Vol 105 (4) ◽  
pp. 459-480
Author(s):  
Carolina Delfini ◽  
Juan M. Acosta ◽  
Vinicius Castro Souza ◽  
Fernando O. Zuloaga

Axonopus P. Beauv. comprises nearly 90, mostly New World, species characterized by having spikelets with the inverse position (i.e., the backs of the upper glume and the upper lemma turned away from the rachis). The genus has been divided into four sections, five series, and three subseries, based exclusively on morphological features. Previous phylogenetic analyses based on a limited sampling of species showed Axonopus to be a monophyletic genus. In this study we increased the number of species sampled (46 species in the combined tree) and sequenced four DNA regions (external transcribed spacer [ETS], internal transcribed spacer [ITS], trnL-F, and ndhF). We tested the monophyly of Axonopus and its traditional infrageneric categories using parsimony, likelihood, and Bayesian inference. Additionally, we performed ancestral character state reconstructions of 45 morphological characters to infer autapomorphies of the species and synapomorphies for the genus and clades. Our findings confirmed Axonopus as a monophyletic genus only when Centrochloa Swallen and Ophiochloa Filg., Davidse & Zuloaga are included within it. Our analyses also showed that, with the exception of section Lappagopsis, infrageneric categories from previous classifications of the genus are artificial. Twenty-one morphological character states were identified as potential autapomorphies; two were reconstructed as potential synapomorphies for Axonopus, whereas 12 were reconstructed as potential synapomorphies for specific clades within the genus. Further molecular analyses, including sequencing of unlinked nuclear genes, are needed in order to reach a robust phylogenetic classification of the genus.


2020 ◽  
Vol 45 (4) ◽  
pp. 794-801
Author(s):  
Caroline Oliveira Andrino ◽  
Marcelo Fragomeni Simon ◽  
Jair Eustáquio Quintino Faria ◽  
André Luiz da Costa Moreira ◽  
Paulo Takeo Sano

Abstract—We describe and illustrate Paepalanthus fabianeae, a new species of Eriocaulaceae from the central portion of the Espinhaço Range in Minas Gerais, Brazil. Previous phylogenetic evidence based on analyses of nuclear (ITS and ETS) and plastid (trnL-trnF and psba-trnH) sequences revealed P. fabianeae as belonging to a strongly supported and morphologically coherent clade containing five other species, all of them microendemic, restricted to the Espinhaço range. Due to the infrageneric classification of Paepalanthus being highly artificial, we preferred not assigning P. fabianeae to any infrageneric group. Paepalanthus fabianeae is known from two populations growing in campos rupestres (highland rocky fields) in the meridional Espinhaço Range. The species is characterized by pseudodichotomously branched stems, small, linear, recurved, and reflexed leaves, urceolate capitula, and bifid stigmas. Illustrations, photos, the phylogenetic position, and a detailed description, as well as comments on habitat, morphology, and affinities with similar species are provided. The restricted area of occurrence allied with threats to the quality of the habitat, mainly due to quartzite mining, justifies the preliminary classification of the new species in the Critically Endangered (CR) category using the guidelines and criteria of the IUCN Red List.


2011 ◽  
Vol 20 (1) ◽  
pp. 161-173
Author(s):  
A.P. Kassatkina

Resuming published and own data, a revision of classification of Chaetognatha is presented. The family Sagittidae Claus & Grobben, 1905 is given a rank of subclass, Sagittiones, characterised, in particular, by the presence of two pairs of sac-like gelatinous structures or two pairs of fins. Besides the order Aphragmophora Tokioka, 1965, it contains the new order Biphragmosagittiformes ord. nov., which is a unique group of Chaetognatha with an unusual combination of morphological characters: the transverse muscles present in both the trunk and the tail sections of the body; the seminal vesicles simple, without internal complex compartments; the presence of two pairs of lateral fins. The only family assigned to the new order, Biphragmosagittidae fam. nov., contains two genera. Diagnoses of the two new genera, Biphragmosagitta gen. nov. (type species B. tarasovi sp. nov. and B. angusticephala sp. nov.) and Biphragmofastigata gen. nov. (type species B. fastigata sp. nov.), detailed descriptions and pictures of the three new species are presented.


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