Patterns of morphological variation within Acacia suaveolens (Mimosaceae)

1995 ◽  
Vol 8 (6) ◽  
pp. 1013 ◽  
Author(s):  
DA Morrison ◽  
AJ Rupp
Keyword(s):  
Morphological Variation ◽  
Environmental Conditions ◽  
Environmental Variables ◽  
Sand Dunes ◽  
Morphological Variability ◽  
Herbarium Specimens ◽  
Morphometric Analyses ◽  
Eastern Australia ◽  
Morphological Differences ◽  
Myall Lakes

Acacia suaveolens shows a considerable degree of morphological variability throughout its range in eastern Australia. Multivariate morphometric analyses of data from 375 herbarium specimens suggest that there are five polythetically distinct forms within this species. The morphological boundaries between these forms are somewhat arbitrary but are closely related to a number of environmental variables. Discrimination between these forms is possible only on the basis of a combination of attributes. In all cases, the distinctions between the forms are maintained in offspring plants grown under controlled environmental conditions, indicating that these morphological differences are genetically fixed. These forms are taxonomically treated as new subspecies. Apart from the typical form (subsp. suaveolens), which is widespread, the following morphological forms have been identified: a form with narrower phyllodes, restricted to the Holocene sand dunes in the Myall Lakes region (subsp. myallensis D. Morrison & A.J. Rupp); a form with wider phyllodes and longer pulvinus, and longer and thicker seeds, occurring in areas with an altitude above 300 m (subsp. montana D. Morrison & A.J. Rupp); a form with wider phyllodes, more flower heads per raceme, thicker seeds, and a small rootstock, restricted to the Grampians region (subsp. grampianensis D. Morrison & A.J. Rupp); and a form with shorter phyllodes, shorter internodes, shorter fruits, thicker seeds and a prostrate habit, occurring on windswept coastal headlands (subsp. prostrata D. Morrison & A.J. Rupp).

scholarly journals Morphological variation in Leptorhynchos squamatus (Gnaphalieae: Asteraceae)

2002 ◽  
Vol 15 (2) ◽  
pp. 205 ◽  
Author(s):  
Christina Flann ◽  
Pauline Y. Ladiges ◽  
Neville G. Walsh
Keyword(s):  
High Altitude ◽  
Morphological Variation ◽  
Environmental Conditions ◽  
Leaf Size ◽  
Alpine Plants ◽  
The Other ◽  
Herbarium Specimens ◽  
South Eastern ◽  
Eastern Australia ◽  
Low Altitude

A study of morphological variation in Leptorhynchos squamatus (Labill.) Less. across its range in south-eastern Australia was undertaken to test the hypothesis that L. squamatus includes two taxa. Phenetic pattern analyses of both field-collected and herbarium specimens on the basis of morphology confirmed two major groups. Bract, cypsela, pappus bristle and leaf characters were particularly important in separating the two groups. The taxa are separated by altitude differences with one being a low-altitude plant found in many habitats and the other being a high-altitude taxon that is a major component of alpine meadows. Lowland plants have dark bract tips, fewer and wider pappus bristles than alpine plants, papillae on the cypselas and more linear leaves. A somewhat intermediate population from the Major Mitchell Plateau in the Grampians shows some alpine and some lowland characters but is included in the lowland taxon. Seeds from five populations (two alpine, two lowland and Major Mitchell) were germinated and plants grown for 18 weeks under four controlled sets of environmental conditions. The experiment showed that leaf size and some other characters are affected by environmental conditions, but that there are underlying genetic differences between the lowland and alpine forms. Leptorhynchos squamatus subsp. alpinus Flann is described here to accommodate the highland taxon.

Genetic variation in Trithuria inconspicua and T. filamentosa (Hydatellaceae): a new subspecies and a hypothesis of apomixis arising within a predominantly selfing lineage

2019 ◽  
Author(s):  
Rob D. Smissen ◽  
Kerry A. Ford ◽  
Paul D. Champion ◽  
Peter B. Heenan
Keyword(s):  
Genetic Variation ◽  
New Zealand ◽  
Morphological Variation ◽  
Genetic Distances ◽  
Herbarium Specimens ◽  
Minimum Evolution ◽  
The North ◽  
Genetic Groups ◽  
Morphological Differences ◽  
High Level

While examining herbarium specimens of Trithuria inconspicua Cheeseman, we observed differences in the stigmatic hairs among plants from New Zealand’s North and South Islands. This motivated us to assess genetic and morphological variation within this species and its sister T. filamentosa Rodway from Tasmania. Samples were collected from lakes in the three disjunct geographic areas where the two species occur. Genetic variation in both species was assessed with simple sequence-repeat (SSR, microsatellite) markers and analyses of genetic distances. We also compared the morphology of northern and southern New Zealand T. inconspicua using fresh material. Samples of each species clustered together in a minimum evolution tree built from genetic distances. Trithuria filamentosa had more genetic diversity than did T. inconspicua. Within T. inconspicua, plants from lakes in the North Island and the South Island formed discrete genetic groups diagnosable by subtle morphological differences. Low levels of heterozygosity in both species are consistent with a high level of selfing, as suggested for other co-sexual Trithuria species, but unusual for a putative apomict. On the basis of genetic and morphological variation, we propose recognition of the northern New Zealand and southern New Zealand lineages of T. inconspicua at subspecies rank.

Diploid and tetraploid cytotypes and subspecies of Odontarrhena tortuosa (Brassicaceae) in Pannonia: differences in morphology, ecology and genome size

Phytotaxa ◽  
2018 ◽  
Vol 358 (2) ◽  
pp. 162
Author(s):  
STANISLAV ŠPANIEL ◽  
LÝDIA HABURAJOVÁ ◽  
VERONIKA CETLOVÁ
Keyword(s):  
Genome Size ◽  
Central Europe ◽  
Morphological Variation ◽  
Pannonian Basin ◽  
Sand Dunes ◽  
Distribution Area ◽  
Flow Cytometric Data ◽  
Flow Cytometric ◽  
Morphological Differences ◽  
Rocky Habitats

Odontarrhena tortuosa is a herbaceous species occurring in steppe and rocky habitats of Eurasia. The present study is focused on the cytogeography and morphological variation of the species’ populations growing in the Pannonian basin (Central Europe), which represents the westernmost part of its distribution area. Flow cytometric analyses have revealed the existence of tetraploid populations, which are reported here for the first time for Central Europe. We analysed the morphological variation of 329 individuals from Slovakia, Hungary and Serbia by multivariate morphometric methods to evaluate morphological differences between two cytotypes (diploids and tetraploids), between the subspecies (O. tortuosa subsp. tortuosa and O. tortuosa subsp. heterophylla) and between populations growing in three regions differing in the type of substrate (rocks, sand dunes and sandy and rocky screes). Although we have not found any clear morphological differences between the cytotypes, we have confirmed several previously reported morphological differences between the two subspecies, which occur in regions differing in the type of substrate. Flow cytometric data also indicate certain differences in monoploid genome size between all groups of populations under comparison. Populations from Serbia differ from other populations of O. tortuosa subsp. tortuosa in morphology and genome size, but due to a lack of data on the genetic variation of the species we suggest no change in taxonomy. For the identification of the two subspecies, we present an updated determination key.

Environmental and spatial factors affect the composition and morphology of tadpole assemblages

2018 ◽  
Vol 96 (10) ◽  
pp. 1130-1136
Author(s):  
N.C.S. Marques ◽  
F. Nomura
Keyword(s):  
Environmental Factors ◽  
Morphological Variation ◽  
Environmental Conditions ◽  
Environmental Variables ◽  
Morphological Diversity ◽  
Oviposition Site ◽  
Spatial Factors ◽  
Assemblage Composition ◽  
Different Types ◽  
Spatial Coordinates

Understanding how community compositions are affected by environmental and spatial factors are essential to provide knowledge about the distributions of species. Furthermore, these factors can play a role in species morphological variation. Tadpoles can be found in different types of aquatic microhabitats, showing a considerable amount of morphological diversity. We hypothesized that tadpole morphological diversity is controlled by ecological and spatial factors other than assemblage attributes, and that tadpole assemblage composition is affected by spatial factors. To test these hypotheses, we recorded the abundance of tadpoles from different ponds, identified eight environmental variables that represented local and landscape descriptors of the ponds, recorded the spatial coordinates of the ponds, and measured the morphological variation of assemblages. Spatial factors significantly affected the composition of tadpole assemblages, while both spatial and environmental factors affected morphological variation. The ability of tadpoles to alter their morphology in response to environmental factors might be a result of poor oviposition site choice, and this probably interacts with spatial factors to control the assemblage composition of tadpoles. Morphological variation is advantageous for tadpoles because it allows them to adjust their morphology to environmental conditions. This study has demonstrated how factors that control the assemblage composition of tadpoles also drive their morphological diversity.

Morphological variation in the mangrove genus Avicennia in Australasia: Systematic and ecological considerations*

1990 ◽  
Vol 3 (2) ◽  
pp. 221 ◽  
Author(s):  
NC Duke
Keyword(s):  
Environmental Factors ◽  
Morphological Variation ◽  
Multivariate Techniques ◽  
Herbarium Specimens ◽  
Southeastern Australia ◽  
Sun And Shade Leaves ◽  
Eastern Australia ◽  
North Eastern ◽  
Sun And Shade ◽  
Shade Leaves

Morphological variation in flowers, fruit and leaves of five Australasian species of Avicennia was assessed using multivariate techniques. Groupings based on 184 herbarium specimens gathered throughout the region showed no intermediates or potential hybrids between species, A. alba, A. integra, A. rumphiana (= A. lanata), A. marina (= A. eucalyptifolia; = A. balanophora) and A. officinalis. The most common and systematically troublesome species, A. marina, was considered further in a regional litter fall survey of 25 Australian sites, and in a detailed field study of eight locations within one estuary. In both studies, morphological variation correlated with environmental factors including air temperature, rainfall, intertidal position and upriver location. Major differences were also observed within individuals, as shown in sun and shade leaves. These observations suggested that many attributes, especially of leaves, were influenced by environmental factors, demonstrating their unsuitability in earlier systematic treatments. Other attributes reflecting putative subspecific genetic variation, included bark character, extent of pubescence on calyx lobes, and stigma position in relation to anthers. These characterise three groupings of A. marina sites, related to major biogeographic zones within this region: southeastern Australia and New Zealand; northern and north-eastern Australia and southern Papua New Guinea; and south-western Australia.* Aust. Inst. Marine Sci. Contrib. No. 489.

Revision of the Calceolaria tripartita s. l. species complex (Calceolariaceae) using multivariate analyses of morphological characters

Phytotaxa ◽  
2014 ◽  
Vol 167 (1) ◽  
pp. 61
Author(s):  
PAMELA PUPPO
Keyword(s):  
Morphological Variation ◽  
Species Complex ◽  
Population Level ◽  
Morphological Characters ◽  
Herbarium Specimens ◽  
Key To Species ◽  
Quantitative Characters ◽  
Components Analysis ◽  
Morphological Differences ◽  
Floral Characters

The morphological variation of the Calceolaria tripartita species complex was evaluated using Principal Components Analysis (PCA) of morphological characters. Fourteen quantitative characters were measured on more than 250 herbarium specimens. The results suggest the recognition of three entities based on floral characters, especially stamen morphology. The distinction between C. mandoniana, C. chelidonioides and C. tripartita s.s. is not supported. The morphological differences between the closely related C. tripartita s.s. and C. chelidonioides were also analyzed using two characters previously used to differentiate them. Finally, the morphological variation of C. tripartita s.s. throughout its geographical range and at an intra-population level was also surveyed. Even though this species is highly variable, no further subdivision is supported morphologically. A taxonomic synopsis and a key to species of the Calceolaria tripartita species complex are provided.

scholarly journals The influence of dynamic environmental interactions on detection efficiency of acoustic transmitters in a large, deep, freshwater lake

2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Natalie V. Klinard ◽  
Edmund A. Halfyard ◽  
Jordan K. Matley ◽  
Aaron T. Fisk ◽  
Timothy B. Johnson
Keyword(s):  
Study Design ◽  
Environmental Conditions ◽  
Power Output ◽  
Environmental Variables ◽  
Acoustic Telemetry ◽  
Detection Efficiency ◽  
Data Interpretation ◽  
Heterogeneous Environments ◽  
Depth Range ◽  
Dynamic Relationship

Abstract Background Acoustic telemetry is an increasingly common method used to address ecological questions about the movement, behaviour, and survival of freshwater and marine organisms. The variable performance of acoustic telemetry equipment and ability of receivers to detect signals from transmitters have been well studied in marine and coral reef environments to inform study design and improve data interpretation. Despite the growing use of acoustic telemetry in large, deep, freshwater systems, detection efficiency and range, particularly in relation to environmental variation, are poorly understood. We used an array of 90 69-kHz acoustic receivers and 8 sentinel range transmitters of varying power output deployed at different depths and locations approximately 100–9500 m apart for 215 days to evaluate how the detection efficiency of acoustic receivers varied spatially and temporally in relation to environmental conditions. Results The maximum distance that tags were detected ranged from 5.9 to 9.3 km. Shallow tags consistently had lower detection efficiency than deep tags of the same power output and detection efficiency declined through the winter months (December–February) of the study. In addition to the distance between tag and receiver, thermocline strength, surface water velocity, ice thickness, water temperature, depth range between tag and receiver, and number of fish detections contributed to explaining variation in detection efficiency throughout the study period. Furthermore, the most significant models incorporated interactions between several environmental variables and tag–receiver distance, demonstrating the complex temporal and spatial relationships that exist in heterogeneous environments. Conclusions Relying on individual environmental variables in isolation to interpret receiver performance, and thus animal behaviour, may be erroneous when detection efficiency varies across distances, depths, or tag types. As acoustic telemetry becomes more widely used to study ecology and inform management, it is crucial to understand its limitations in heterogeneous environments, such as freshwater lakes, to improve the quality and interpretation of data. We recommend that in situ range testing and retrospective analysis of detection efficiency be incorporated into study design for telemetry projects. Furthermore, we caution against oversimplifying the dynamic relationship between detection efficiency and environmental conditions for the sake of producing a correction that can be applied directly to detection data of tagged animals when the intended correction may not be justified.

Between- and within-breed morphological variability in Moroccan sheep breeds

2016 ◽  
Vol 58 ◽  
pp. 91-100 ◽  
Author(s):  
I. Boujenane ◽  
D. Petit
Keyword(s):  
Multivariate Analyses ◽  
Morphological Variability ◽  
Tail Length ◽  
Morphological Characterization ◽  
Total Variance ◽  
High Association ◽  
Sheep Breeds ◽  
Selection Strategies ◽  
Morphological Differences

SummaryThe objective of this study was a morphological characterization of five Moroccan sheep breeds (Béni Guil, Boujaâd, D'man, Sardi and Timahdite) to assess between- and within-breed variability using multivariate analyses. Fourteen morphological measurements were collected on 876 adult animals of both sexes in 98 different flocks located in 22 geographic localities of five breeds. The multiple analysis of variance revealed that significant morphological differences existed between breeds. The overall proportion of total variance due to between-breed component was 28.3 percent. The factor analysis revealed three factors accounting for 50.1, 11.8 and 7.54 percent of total variance. The first factor had high loadings for variables relating to body size, whilst the second factor had high association with traits reflecting tail length and ear size. The third factor had high loadings for wool trait. The squared Mahalanobis distance between the five sheep breeds were highly significant (P< 0.001). The largest morphological divergence was shown between Béni Guil and Sardi breeds (23.5) and the smallest one was between Boujaâd and Sardi breeds (3.54). The discriminant functions clearly discriminated and assigned 94.4 percent of Béni Guil, 79.7 of Boujaâd, 88.5 percent of D'man, 86.7 of Sardi and 80.1 percent of Timahdite sheep into their breed of origin. Overall morphological differences observed within-breeds were due for 18.1 percent to geographic locality and for 20.7 percent to flock management. It was concluded that the information reported in this study will be the basis for the establishment of characterization and selection strategies for Moroccan sheep.

A reassessment of Dioon merolae (Zamiaceae) leads to the description of Dioon salas-moralesae, a new cycad species from Southeastern Oaxaca, Mexico

Phytotaxa ◽  
2021 ◽  
Vol 528 (2) ◽  
pp. 93-110
Author(s):  
JOSÉ SAID GUTIÉRREZ-ORTEGA ◽  
MIGUEL ANGEL PÉREZ-FARRERA ◽  
JEFFREY CHEMNICK ◽  
TIMOTHY J. GREGORY
Keyword(s):  
New Species ◽  
Morphological Variation ◽  
Related Species ◽  
Statistical Tests ◽  
Distinct Species ◽  
Closely Related Species ◽  
Morphometric Variation ◽  
Isthmus Of Tehuantepec ◽  
Morphological Differences ◽  
Recent Evaluation

The cycad genus Dioon comprises 17 species from Mexico and Honduras, all of them delimited based on their morphological variation and geographic distribution. A recent evaluation of the biological variation among Dioon populations from Oaxaca and Chiapas, Mexico, demonstrated that the concept of the species Dioon merolae actually consists of three lineages that should be recognized as different taxa. One lineage was already described as Dioon oaxacensis, leaving the concept of Dioon merolae comprising two lineages distributed on both sides of the Isthmus of Tehuantepec. However, there are conspicuous morphological differences between these two lineages. Here, we tested whether such a differentiation within the concept of Dioon merolae merits the differentiation of two different taxa. We evaluated the qualitative and morphometric variation among populations belonging to the Dioon merolae lineages, and compared it with the closely related species Dioon oaxacensis. Morphological observations and statistical tests demonstrated that the populations of southeastern Oaxaca, traditionally considered as part of Dioon merolae, represent a distinct species that we described as Dioon salas-moralesae. Identifying the diagnostic characters of this new species helps enable an understanding of the criteria that should be considered to delineate the boundaries between other cycad species.

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