PHYLOGENETIC SYSTEMATICS AS A GUIDE TO UNDERSTANDING FEATURES AND POTENTIAL MORPHOLOGICAL CHARACTERS OF THE CENTRIC DIATOM FAMILY THALASSIOSIRACEAE

1994 ◽  
Vol 9 (2) ◽  
pp. 429-450 ◽  
Author(s):  
Edward Theriot ◽  
Karen Serieyssol
Keyword(s):  
Morphological Characters ◽  
Phylogenetic Systematics ◽  
Centric Diatom

Sexual reproduction in the Peronosporomycetes (chromistan fungi)

1995 ◽  
Vol 73 (S1) ◽  
pp. 712-724 ◽  
Author(s):  
Michael W. Dick
Keyword(s):  
Sexual Reproduction ◽  
Dense Body ◽  
Morphological Characters ◽  
Life History Strategies ◽  
Phylogenetic Systematics ◽  
Taxonomic Identification ◽  
Phylogenetic Significance ◽  
Key Words Meiosis ◽  
Internal Morphology ◽  
Ecological Implications

An overview of sexual reproduction in the Peronosporomycetes leads to the recognition of constant features and variable traits. Variation in characters is accorded different weighting depending on its use for taxonomic identification or phylogenetic systematics. The phylogenetic significance of features of gametangial morphogenesis, such as vacuolation and the patterns of nuclear meioses and abortions, can be related to morphological characters such as the persistence of periplasm and oogonial and oospore wall deposition. The cellular reorganization occurring in the oogonium and oospores, particularly in relation to the possible functions of the dense body vesicle system and the glucan, phosphate, and lipid oospore reserves, may be critical for the internal morphology of the mature oospore and its function. Such differences are valuable for morphometric analysis, which lends itself to new identification procedures. The ecological implications of these differences in the production of oogonia and oospores are considered; sexual reproduction (its frequency or absence) may be crucial for successful life-history strategies in biodiversity. Key words: meiosis, karyogamy, syngamy, morphogenesis, morphometry, wall membranes.

Phylogenetic systematics of day geckos, genus Phelsuma, based on molecular and morphological data (Squamata: Gekkonidae)

Zootaxa ◽  
2010 ◽  
Vol 2429 (1) ◽  
pp. 1 ◽  
Author(s):  
SARAH ROCHA ◽  
HERBERT RÖSLER ◽  
PHILIP-SEBASTIAN GEHRING ◽  
FRANK GLAW ◽  
DAVID POSADA ◽  
...  
Keyword(s):  
Molecular Markers ◽  
Morphological Characters ◽  
Molecular Data ◽  
Morphological Data ◽  
Species Assemblages ◽  
Rrna Gene ◽  
Phylogenetic Systematics ◽  
Multigene Phylogeny ◽  
Species Groups ◽  
The 16S Rrna Gene

We review the intrageneric systematics of day geckos, genus Phelsuma (Squamata: Sauria: Gekkonidae) in the light of a recently published multigene phylogeny, and provide an overview of 19 selected chromatic, morphological and behavioural characters for all currently recognized species and subspecies in the genus. To replace previous attempts of dividing the genus into phenetic species assemblages, we propose the following monophyletic species groups and summarize the morphological characters that partly support this grouping: Phelsuma barbouri group (P. barbouri, P. pronki); P. dubia group (P. berghofi, P. dubia, P. flavigularis, P. hielscheri, P. malamakibo, P. modesta, P. nigristriata, P. ravenala); P. mutabilis group (P. borai, P. breviceps, P. mutabilis); P. cepediana group (P. borbonica, P. cepediana, P. guentheri, P. guimbeaui, P. inexpectata, P. ornata, P. rosagularis as well as the extinct species P. edwardnewtonii and P. gigas); P. astriata group (P. astriata, P. sundbergi); P. madagascariensis group (P. abbotti, P. grandis, P. guttata, P. kochi, P. madagascariensis, P. parkeri, P. seippi and probably P. masohoala); P. lineata group (P. antanosy, P. comorensis, P. kely, P. lineata, P. pusilla, P. quadriocellata and probably P. hoeschi); P. laticauda group (P. laticauda, P. pasteuri, P. robertmertensi, P. v-nigra); P. klemmeri group (P. klemmeri); P. andamanense group (P. andamanense) and P. standingi group (P. standingi). Due to their equivocal placements based on different molecular markers, we refrain from assigning P. serraticauda and P. vanheygeni to any of these species groups at this time. We complement the molecular data with new trees based on partial sequences of the 16S rRNA gene for the P. madagascariensis- and P. lineata groups and propose to elevate P. lineata dorsivittata and P. quadriocellata parva to full species rank as P. dorsivittata and P. parva.

Phylogenetic systematics of weevils (Coleoptera: Curculionoidea): A reappraisal based on larval and adult morphology

2000 ◽  
Vol 31 (1) ◽  
pp. 43-58 ◽  
Author(s):  
J.J. Morrone ◽  
A.E. Marvaldi
Keyword(s):  
Cladistic Analysis ◽  
Sister Group ◽  
Morphological Characters ◽  
Sister Taxon ◽  
Sister Group Relationship ◽  
Phylogenetic Systematics ◽  
Adult Morphology ◽  
Terminal Units ◽  
Relationship Of

AbstractA cladistic analysis of Curculionoidea based on 100 morphological characters (28 from larvae and 72 from adults) is presented. The 13 terminal taxa correspond to 7 extant families of Curculionoidea of which the largest, Curculionidae, is represented by 7 smaller units. The terminal units are defined by morphological autapomorphies taken from published information on larvae and adults. The chrysomeloid Palophaginae was used as outgroup. The cladogram shows that there is a basal dichotomy in the superfamily, Nemonychidae-Anthribidae being the monophyletic sister taxon to the remaining families, which follow the sequence Belidae, Attelabidae, Caridae, Brentidae, and Curculionidae. The units of Curculionidae are related as follows: Ithycerinae, Microcerinae, Brachycerinae, Ocladiinae, Dryophthorinae, Erirhininae, and 'Curculionidae s.str.'. Important areas where further work should be directed are: the sister group relationship of Nemonychidae and Anthribidae, and the recognition of monophyletic subfamilies within the Curculionidae s.str. as well as the placement of Platypodinae.

Phylogenetic systematics and biogeography of the sand crab families Albuneidae and Blepharipodidae (Crustacea : Anomura : Hippoidea)

2009 ◽  
Vol 23 (1) ◽  
pp. 1 ◽  
Author(s):  
Christopher B. Boyko ◽  
Alan W. Harvey
Keyword(s):  
Morphological Characters ◽  
Sensu Stricto ◽  
Morphological Evidence ◽  
Phylogenetic Systematics ◽  
Fossil Species ◽  
The Family ◽  
Outgroup Species ◽  
Phylogenetic Hypotheses

Many unrelated crustaceans sharing a suite of convergent specialisations for a sand-burrowing existence have been placed in the anomuran family Albuneidae at one time or another. Although most of these non-albuneids have long since been reassigned to other families, recent molecular and morphological evidence has suggested a further split within the family between the Albuneidae (sensu stricto) and the Blepharipodidae. We used 173 morphological characters to test phylogenetic hypotheses about the monophyly of the Albuneidae and Blepharipodidae, as well as their constituent genera. We included 61 known species of albuneids and blepharipodids (including eight fossil species) and six outgroup species in five anomuran families. Analyses confirm that the Albuneidae and the Blepharipodidae are separate and monophyletic taxa that have convergently evolved similar adaptations to sand burrowing. Zygopa Holthuis, 1961 and Squillalbunea Boyko, 2002 are sister-taxa to the rest of the Albuneidae; all other Recent genera of albuneids are well supported and form two clades at the subfamily level. An Indo-Pacific origin for the Albuneidae is proposed and various scenarios regarding possible routes of dispersal are discussed.

scholarly journals Quantified ensemble 3D surface features modeled as a window on centric diatom valve morphogenesis

2018 ◽  
Author(s):  
Janice L. Pappas
Keyword(s):  
Morphological Changes ◽  
Morphological Characters ◽  
Surface Generation ◽  
Centric Diatom ◽  
Surface Features ◽  
3D Surface ◽  
Algorithmic Techniques ◽  
Face Structure ◽  
Valve Formation ◽  
Diatom Valve

AbstractMorphological surface features are a record of genetic and developmental processes as well as environmental influences. The 3D geometric “terrain” of the surface consists of slopes via tangents, peaks and valleys via normals, smoothness of the transition between peaks and valleys, and point connections as flatness or curvature among all features. Such geometric quantities can be used to indicate morphological changes in valve formation over time. Quantified 3D surface features as geometric pattern ensembles may be representative of structural snapshots of the morphogenetic process.For diatoms, valve formation and pattern morphogenesis has been modeled using Turing-like and other algorithmic techniques to mimic the way in which diatoms exhibit the highly diverse patterns on their valve surfaces. How the created surface features are related to one another is not necessarily determined via such methods. With the diatom valve face structure of layered areolae, cribra, and other morphological characters, valve formation exhibits different combined geometries unfolding as 3D structural ensembles in particular spatial arrangements. Quantifying ensemble 3D surface geometries is attainable via models devised using parametric 3D equations and extracting surface features via partial derivatives for slopes, peaks and valleys, smoothness, and flatness as feature connectedness. Differences in ensemble 3D surface features may be used to assess structural differences among selected diatom genera as indicators of different valve formation sequences in surface generation and morphogenesis.

A New Species of Justicia (Acanthaceae: Acanthoideae: Justicieae) from Northeastern Brazil

2020 ◽  
Vol 45 (2) ◽  
pp. 328-333
Author(s):  
Camila Alcantara ◽  
Gleison Soares ◽  
Francisco de Assis Ribeiro dos Santos ◽  
Marccus Alves
Keyword(s):  
New Species ◽  
Rio Grande ◽  
Morphological Characters ◽  
Northeastern Brazil ◽  
Distribution Map ◽  
Key To Species ◽  
A New Species

Abstract—Justicia rubrobracteata, a new species from northeastern Brazil, is described and illustrated. The new species is morphologically similar to J. aequilabris due to its shrubby habit, and terminal and axillary spicate inflorescences with red flowers. However, J. rubrobracteata is differentiated mainly by the shape and color of its bracts and bracteoles as well as an orangish macula in the corolla, and a torulose capsule. In addition, J. rubrobracteata is only known from northeastern Brazil, from the states of Paraíba and Rio Grande do Norte, while J. aequilabris is widely distributed in Bolivia, Brazil, and Paraguay. A table with the main morphological characters of both species is included, as well as photographs, a key to species of Justicia for the states of Paraíba and Rio Grande do Norte in northeastern Brazil, a distribution map of both species, and conservation data for the new species.

Comparative Analysis of Genetic and Morphological Variation within the Platanthera hyperborea Complex (Orchidaceae)

2020 ◽  
Vol 45 (4) ◽  
pp. 767-778
Author(s):  
Eranga Wettewa ◽  
Nick Bailey ◽  
Lisa E. Wallace
Keyword(s):  
North America ◽  
Diploid Species ◽  
Morphological Characters ◽  
Evolutionary Patterns ◽  
Founding Population ◽  
Multiple Origins ◽  
Geographic Structure ◽  
Species Complexes ◽  
Nuclear Its ◽  
Cryptic Taxa

Abstract—Species complexes present considerable problems for a working taxonomy due to the presence of intraspecific variation, hybridization, polyploidy, and phenotypic plasticity. Understanding evolutionary patterns using molecular markers can allow for a more thorough assessment of evolutionary lineages than traditional morphological markers. In this study, we evaluated genetic diversity and phylogenetic patterns among taxa of the Platanthera hyperborea (Orchidaceae) complex, which includes diploid (Platanthera aquilonis) and polyploid (Platanthera hyperborea, P. huronensis, and P. convallariifolia) taxa spanning North America, Greenland, Iceland, and Asia. We found that three floral morphological characters overlap among the polyploid taxa, but the diploid species has smaller flowers. DNA sequence variation in a plastid (rpL16 intron) and a nuclear (ITS) marker indicated that at least three diploid species have contributed to the genomes of the polyploid taxa, suggesting all are of allopolyploid origin. Platanthera convallariifolia is most like P. dilatata and P. stricta, whereas P. huronensis and P. hyperborea appear to have originated from crosses of P. dilatata and P. aquilonis. Platanthera huronensis, which is found across North America, has multiple origins and reciprocal maternal parentage from the diploid species. By contrast, P. hyperborea, restricted to Greenland and Iceland, appears to have originated from a small founding population of hybrids in which P. dilatata was the maternal parent. Geographic structure was found among polyploid forms in North America. The area of Manitoba, Canada appears to be a contact zone among geographically diverse forms from eastern and western North America. Given the geographic and genetic variation found, we recommend continued recognition of four green-flowered species within this complex, but caution that there may be additional cryptic taxa within North America.

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