A phylogenetic study of the Lutrinae (Carnivora; Mustelidae) using morphological data

1987 ◽  
Vol 65 (10) ◽  
pp. 2536-2544 ◽  
Author(s):  
C. G. van Zyll de Jong
Keyword(s):  
Morphological Data ◽  
Canonical Variate ◽  
Phylogenetic Study ◽  
Independent Evidence ◽  
Old World ◽  
River Otters ◽  
Extant Species ◽  
Qualitative Characters ◽  
Relationship Of ◽  
High Degree

The phylogenetic relationship of the 13 extant species of otters were analyzed by canonical variate analysis using mensural data and by Wagner analysis using qualitative characters. The results of the two analyses showed a high degree of concordance. The information of the generalized distance (D) and Wagner trees was combined in an Adams-2 consensus tree. The phylogenetic hypothesis generated deviates from currently accepted classifications chiefly in separating the species of river otters of the genus Lutra, as it is generally conceived, into two groups of genera. One, the New World river otters (Lontra), is a monophyletic group phylogenetically linked to the African and Asian clawless otters (Aonyx and Amblonyx). The other group, their Old World ecological counterparts (Lutra), constitutes a different clade. Enhydra and Pteronura are the most divergent of living otters, the former being closer to the clawless otters and the latter to the smooth-coated otter (Lutrogale), which in turn is phylogenetically close to the Old World river otters (Lutra). Available independent evidence, although incomplete, does not contradict the hypothesis.

Morphometric discrimination among sibling species in the fulva–rudis–texana complex of the ant genus Aphaenogaster (Hymenoptera: Formicidae)

1996 ◽  
Vol 74 (3) ◽  
pp. 528-559 ◽  
Author(s):  
Gary J. Umphrey
Keyword(s):  
Canonical Variate ◽  
Similar Species ◽  
Undescribed Species ◽  
Morphometric Measurements ◽  
Morphometric Variation ◽  
Linear Discriminant ◽  
Interspecific Differences ◽  
Variate Analysis ◽  
Qualitative Characters ◽  
High Degree

The fulva–rudis–texana complex of the ant genus Aphaenogaster includes A. fulva, A. rudis, A. texana, and morphologically similar species. Morphometric and other morphological investigations were conducted on colony representatives of 10 forms (4 likely representing undescribed species) that were previously identified using cytogenetic and electrophoretic markers. In workers, most qualitative characters exhibit such a high degree of size-associated intraspecific variation relative to interspecific differences that they are not reliable for identification. Linear discriminant analysis and canonical variate analysis on 12 morphometric measurements were used to optimize classification and define a morphometric habitus for each form. Two-variable scatterplots clarify the nature of morphometric variation in the complex and provide simple characters that will reliably separate numerous pairs of forms. Indices appear to be of little taxonomic value in this complex. A preliminary key to the workers of the complex summarizes the most important taxonomic characters. This key substantially improves the ability to recognize morphologically most members of the complex, but sometimes only genetic evidence is definitive.

Three new cribrimorph bryozoans (order Cheilostomatida) from the early Miocene of Argentina, with a discussion on spinocystal shield morphologies

2021 ◽  
pp. 1-15
Author(s):  
Juan López-Gappa ◽  
Leandro M. Pérez ◽  
Ana C.S. Almeida ◽  
Débora Iturra ◽  
Dennis P. Gordon ◽  
...  
Keyword(s):  
Type Species ◽  
Systematic Position ◽  
Early Miocene ◽  
Morphological Data ◽  
Fossil Species ◽  
Extant Species ◽  
The Family ◽  
Subjective Synonym

Abstract Bryozoans with calcified frontal shields formed by the fusion of costae, collectively constituting a spinocyst, are traditionally assigned to the family Cribrilinidae. Today, this family is regarded as nonmonophyletic. In the Argentine Cenozoic, cribrilinids were until recently represented by only two fossil species from the Paleocene of Patagonia. This study describes the first fossil representatives of Jolietina and Parafigularia: J. victoria n. sp. and P. pigafettai n. sp., respectively. A fossil species of Figularia, F. elcanoi n. sp., is also described. The material comes from the early Miocene of the Monte León and Chenque formations (Patagonia, Argentina). For comparison, we also provide redescriptions of the remaining extant species of Jolietina: J. latimarginata (Busk, 1884) and J. pulchra Canu and Bassler, 1928a. The systematic position of some species previously assigned to Figularia is here discussed. Costafigularia n. gen. is erected, with Figularia pulcherrima Tilbrook, Hayward, and Gordon, 2001 as type species. Two species previously assigned to Figularia are here transferred to Costafigularia, resulting in C. jucunda n. comb. and C. tahitiensis n. comb. One species of Figularia is reassigned to Vitrimurella, resulting in V. ampla n. comb. The family Vitrimurellidae is here reassigned to the superfamily Cribrilinoidea. The subgenus Juxtacribrilina is elevated to genus rank. Inferusia is regarded as a subjective synonym of Parafigularia. Parafigularia darwini Moyano, 2011 is synonymized with I. taylori Kuklinski and Barnes, 2009, resulting in Parafigularia taylori n. comb. Morphological data suggest that these genera comprise different lineages, and a discussion on the disparities among cribrilinid (sensu lato) spinocysts is provided. UUID: http://zoobank.org/215957d3-064b-47e2-9090-d0309f6c9cd8

scholarly journals Interactions Between Chill-Hours and Degree-Days Affect Carpogenic Germination in Monilinia vaccinii-corymbosi

2001 ◽  
Vol 91 (1) ◽  
pp. 77-83 ◽  
Author(s):  
H. Scherm ◽  
A. T. Savelle ◽  
P. L. Pusey
Keyword(s):  
Laboratory Experiments ◽  
Field Experiments ◽  
Degree Days ◽  
Carpogenic Germination ◽  
Conditioning Period ◽  
Low Degree ◽  
Heating Degree Days ◽  
Relationship Of ◽  
High Degree ◽  
The Relationship

The relationship of cumulative chill-hours (hours with a mean temperature <7.2°C) and heating degree-days (base 7.2°C) to carpogenic germination of pseudosclerotia of Monilinia vaccinii-corymbosi, which causes mummy berry disease of blueberry, was investigated. In two laboratory experiments, pseudosclerotia collected from rabbiteye blueberry in Georgia were conditioned at 5 to 6°C for 26 to 1,378 h prior to placement in conditions favorable for germination and apothecium development. The number of chill-hours accumulated during the conditioning period affected the subsequent proportion of pseudosclerotia that germinated and produced apothecia, with the greatest incidence of carpogenic germination occurring after intermediate levels of chilling (≈700 chill-hours). The minimum chilling requirement for germination and apothecium production was considerably lower than that reported previously for pseudo-sclerotia from highbush blueberry in northern production regions. The rate of carpogenic germination was strongly affected by interactions between the accumulation of chill-hours and degree-days during the conditioning and germination periods; pseudosclerotia exposed to prolonged chilling periods, once transferred to suitable conditions, germinated and produced apothecia more rapidly (after fewer degree-days had accumulated) than those exposed to shorter chilling periods. Thus, pseudosclerotia of M. vaccinii-corymbosi are adapted to germinate carpogenically following cold winters (high chill-hours, low degree-days) as well as warm winters (low chill-hours, high degree-days). Results were validated in a combined field-laboratory experiment in which pseudosclerotia that had received various levels of natural chilling were allowed to germinate in controlled conditions in the laboratory, and in two field experiments in which pseudosclerotia were exposed to natural chilling and germination conditions. A simple model describing the timing of apothecium emergence in relation to cumulative chill-hours and degree-days was developed based on the experiments. The model should be useful for better timing of field scouting programs for apothecia to aid in management of primary infection by M. vaccinii-corymbosi.

scholarly journals Intergeneric Relationships within the Early-Diverging Angiosperm Family Nymphaeaceae Based on Chloroplast Phylogenomics

2018 ◽  
Vol 19 (12) ◽  
pp. 3780 ◽  
Author(s):  
Dingxuan He ◽  
Andrew Gichira ◽  
Zhizhong Li ◽  
John Nzei ◽  
Youhao Guo ◽  
...  
Keyword(s):  
Genome Structure ◽  
Morphological Data ◽  
Basal Angiosperm ◽  
Phylogenetic Position ◽  
Data Set ◽  
Protein Coding ◽  
Plastid Genomes ◽  
Chloroplast Genomes ◽  
Gene Data ◽  
High Degree

The order Nymphaeales, consisting of three families with a record of eight genera, has gained significant interest from botanists, probably due to its position as a basal angiosperm. The phylogenetic relationships within the order have been well studied; however, a few controversial nodes still remain in the Nymphaeaceae. The position of the Nuphar genus and the monophyly of the Nymphaeaceae family remain uncertain. This study adds to the increasing number of the completely sequenced plastid genomes of the Nymphaeales and applies a large chloroplast gene data set in reconstructing the intergeneric relationships within the Nymphaeaceae. Five complete chloroplast genomes were newly generated, including a first for the monotypic Euryale genus. Using a set of 66 protein-coding genes from the chloroplast genomes of 17 taxa, the phylogenetic position of Nuphar was determined and a monophyletic Nymphaeaceae family was obtained with convincing statistical support from both partitioned and unpartitioned data schemes. Although genomic comparative analyses revealed a high degree of synteny among the chloroplast genomes of the ancient angiosperms, key minor variations were evident, particularly in the contraction/expansion of the inverted-repeat regions and in RNA-editing events. Genome structure, and gene content and arrangement were highly conserved among the chloroplast genomes. The intergeneric relationships defined in this study are congruent with those inferred using morphological data.

Photoreceptor coupling in turtle retina

1998 ◽  
Vol 15 (4) ◽  
pp. 755-764 ◽  
Author(s):  
M.L. FIRSOV ◽  
D.G. GREEN
Keyword(s):  
Receptive Field ◽  
Gap Junctions ◽  
Direct Evidence ◽  
Physiological Responses ◽  
The Other ◽  
Morphological Data ◽  
Chelydra Serpentina ◽  
Intracellular Injection ◽  
Coupled Cells ◽  
High Degree

Photoreceptors in the isolated turtle retina of two species of turtle, Chelydra serpentina and Pseudemus scripta elegans, were penetrated with double-barrel electrodes. Physiological responses were recorded through one barrel and Neurobiotin tracer was injected from the other. Intracellular injection of Neurobiotin revealed patterns of tracer-coupled photoreceptors. Both the patterns of tracer coupling and the electrophysiology suggest a high degree of specificity of connections. Rods seem to be coupled only to rods and green and red cones seem to be coupled to cones of the same spectral type. Receptive-field profiles, measured with a thin, sharply focused slit of light, often had well-defined peaks and troughs in sensitivity. We have taken advantage of this observation and used the position of a peak in sensitivity to locate the position on the retina of a coupled cell. In one rod, it was possible to correlate physiological and morphological data and to show that the peaks in the physiological receptive field occurred at positions on the retina where there were dye-coupled cells. This provides direct evidence that gap junctions produce the physiological coupling between rods.

scholarly journals Structure, expression and phylogenetic analysis of the gene encoding actin I in Pneumocystis carinii.

Genetics ◽  
1994 ◽  
Vol 137 (3) ◽  
pp. 743-750 ◽  
Author(s):  
L D Fletcher ◽  
J M McDowell ◽  
R R Tidwell ◽  
R B Meagher ◽  
C C Dykstra
Keyword(s):  
Phylogenetic Analysis ◽  
Essential Gene ◽  
Pneumocystis Carinii ◽  
Comparative Sequence Analysis ◽  
Cdna Clones ◽  
Actin Gene ◽  
Gene Encoding ◽  
Actin Protein ◽  
Relationship Of ◽  
High Degree

Abstract Actin is a major component of the cytoskeleton and one of the most abundant proteins found in eukaryotic cells. Comparative sequence analysis shows that this essential gene has been highly conserved throughout eukaryotic evolution making it useful for phylogenetic analysis. Complete cDNA clones for the actin-encoding gene were isolated and characterized from Pneumocystis carinii purified from immunosuppressed rat lungs. The nucleotide sequence encodes a protein of 376 amino acids. The predicted actin protein of P. carinii shares a high degree of conservation to other known actins. Only one major actin gene was found in P. carinii. The P. carinii actin sequence was compared with 30 other actin sequences. Gene phylogenies constructed using both neighbor-joining and protein parsimony methods places the P. carinii actin sequence closest to the majority of the fungi. Since the phylogenetic relationship of P. carinii to fungi and protists has been questioned, these data on the actin gene phylogeny support the grouping of P. carinii with the fungi.

scholarly journals Intrapersonal Conflict as a Factor of Adaptation of Students to Conditions of Teaching at Universities

2016 ◽  
Vol 70 ◽  
pp. 1-7
Author(s):  
Natalia Gerasimova ◽  
Inna Gerasymova
Keyword(s):  
Interpersonal Conflict ◽  
Personality Factors ◽  
Self Identity ◽  
Individual Personality ◽  
Intrapersonal Conflict ◽  
Individual Differentiation ◽  
The Mind ◽  
Relationship Of ◽  
High Degree ◽  
The Impact

The article reviews the current state of studying the problem of interpersonal conflict as a factor in adaptation, characterized by consideration of the relationship of these categories on two levels: intrapersonal conflict is studied as a driving force, a source of self-in the process of adaptation and as a leading indicator of complications adaptation. It is determined that the impact of interpersonal conflict in the course of adaptation depends on self-identity in a complex interaction of external (socially determined) and internal (individual personality) factors. It is indicated that psychological content intrapersonal conflict experiences have a high degree of individual differentiation and thus determine the uniqueness of perception and interpretation of a specific person. An indicator of the transition from one level to another intrapersonal difficulties acts vulnerability to conflict self-relations context of inner experience. The nature of the adaptation of the student is determined by the internal model and solve interpersonal experiences complications, which are formed in the mind and form the basis of individual experience.

scholarly journals Micromorphological, anatomical and molecular study of Hedera species (Araliaceae) in Iran

2020 ◽  
Vol 63 (2) ◽  
pp. 91-101
Author(s):  
Elham Amini ◽  
Fatemeh Nasrollahi ◽  
Ali Sattarian ◽  
Mahboobeh Haji Moradkhani ◽  
Sohrab Boozarpour ◽  
...  
Keyword(s):  
North Africa ◽  
Phylogenetic Analyses ◽  
Molecular Study ◽  
Molecular Characteristics ◽  
Nrdna Its ◽  
Anticlinal Wall ◽  
Data Set ◽  
Phylogenetic Methods ◽  
Extant Species ◽  
Qualitative Characters

Hedera, with 12 extant species, is a genus of evergreen climbers native to Europe, north Africa, and south Asia. In this study, the micromorphological, anatomical structure and molecular evidences of 11 populations from two species of Hedera (H. helix and H. pastuchovii) have been considered to evaluate the relationships in Hedera. In total, seven quantitative and qualitative characters of pollen were selected and measured. Based on this study, the anticlinal wall and surface sculpturing of seed support for separation of two species of Hedera. Micromorphology of epidermis illustrated two types of epidermal cells: puzzle-shaped and polygonal cells. Using nuclear (nrDNA ITS) marker, we reconstructed phylogenetic relationships within two species of Hedera. This data set was analyzed by phylogenetic methods including Bayesian inference, maximum likelihood, and maximum parsimony. In phylogenetic analyses, all members of two species formed a well-supported clade (PP = 1; ML/BS = 100/100) and divided into two major clades (A and B). Neighbor Net diagram demonstrated separation of the studied populations. The results showed that these taxa differ in taxonomically important micromorphological, anatomical and molecular characteristics and these data provide reliable evidence for separation of these two species.

Interface structure of face-centered-cubic-Ti thin film grown on 6H–SiC substrate

2000 ◽  
Vol 15 (10) ◽  
pp. 2121-2124 ◽  
Author(s):  
Y. Sugawara ◽  
N. Shibata ◽  
S. Hara ◽  
Y. Ikuhara
Keyword(s):  
Thin Film ◽  
Orientation Relationship ◽  
High Resolution Electron Microscopy ◽  
Electron Beam Evaporation ◽  
Face Centered Cubic ◽  
High Adhesion ◽  
Resolution Electron ◽  
Face Centered ◽  
Relationship Of ◽  
High Degree

A titanium thin film was deposited on the flat (0001) face of a 6H–SiC by electron beam evaporation at room temperature in a vacuum of 5.1 × 10−8 Pa. The Ti film was epitaxially grown on the surface, and the interface between Ti and SiC was characterized by high-resolution electron microscopy. It was found that the structure of the deposited titanium is face-centered cubic (fcc), although bulk titanium metal usually has a hexagonal close-packed or body-centered cubic crystal structure. We believe that the unusual fcc structure of Ti thin film is due to the high adhesion of the film to the substrate and the high degree of coherency between them. The orientation relationship of the fcc-Ti/6H–SiC interface was (111)fcc-Ti//(0001)6H–SiC and [110]fcc-Ti//[1120]6H−SiC. Preliminary calculations indicate that this orientation relationship maximizes the lattice coherency across the interface.

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