The taxonomy of the Carex pensylvanica complex (Cyperaceae) in North America

1983 ◽  
Vol 61 (6) ◽  
pp. 1692-1717 ◽  
Author(s):  
William J. Crins ◽  
Peter W. Ball
Keyword(s):  
North America ◽  
Principal Components Analysis ◽  
Principal Components ◽  
Morphological Variation ◽  
Discriminant Functions ◽  
Distribution Maps ◽  
Variation Patterns ◽  
Carex Pensylvanica ◽  
Components Analysis ◽  
Eastern Species

The Carex pensylvanica complex consists of four North American taxa. Morphological variation patterns within the complex were examined using principal-components analysis and discriminant-functions analysis. These results indicate that two eastern species, C. lucorum Willdenow ex Link, and C. pensylvanica Lamarck, and one western species, C. inops Bailey, should be recognized. The latter species comprises two subspecies, C. inops subsp. inops and C. inops subsp. heliophila (Mackenzie) Crins, comb. nov. Cytological and geographical evidence lend support to this classification. A key and distribution maps for the taxa are provided.

Morphological variation in relation to the taxonomy of the destructor group of the genus Cherax

1988 ◽  
Vol 2 (1) ◽  
pp. 55 ◽  
Author(s):  
A Sokol
Keyword(s):  
Principal Components Analysis ◽  
Principal Components ◽  
Morphological Variation ◽  
Analysis Of Covariance ◽  
Bivariate Analysis ◽  
Morphological Divergence ◽  
Analysis Techniques ◽  
Late Tertiary ◽  
Outgroup Species ◽  
Components Analysis

The present study was directed at clarifying the taxonomy of the destructor group of the genus Cherax. This group was defined by Riek (1969) to include four species: C. destructor Clark, C. albidus Clark, C. davisi Clark and C. esculus Riek. Approximately 1600 specimens representing over 80 localities were examined, including specimens from three outgroup species; C. rotundus, C. punctatus and C. dispar. Variation in 16 metric and 30 multistate characters was analysed by bivariate (analysis of covariance) and multivariate (principal components analysis) techniques. None of the taxonomic analyses supported the distinction of C. davisi or C. esculus from C. destructor, which suggests that the two former species be synonymised with the last. By contrast, C. albidus was found to be morphologically distinct. The pattern and timing of speciation of C. albidus and C. destructor are unclear but may relate to the increase in aridity in inland Australia during the late Tertiary. The analyses also indicated that heterochrony may underly the morphological divergence of these two species.

Morphological Variation in the Dentition and Skull of the Australian Ghost Bat, Macroderma-Gigas (Microchiroptera, Megadermatidae)

1990 ◽  
Vol 38 (3) ◽  
pp. 263 ◽  
Author(s):  
S Hand ◽  
A York
Keyword(s):  
Principal Components Analysis ◽  
Principal Components ◽  
Morphological Variation ◽  
Univariate Analysis ◽  
South Australia ◽  
Clinal Variation ◽  
Clear Cut ◽  
Cranial Measurements ◽  
Southern Central ◽  
Components Analysis

Morphological variation in the dentition and some cranial characters of the Australian ghost bat, Macroderma gigas, is reviewed by means of univariate and multivariate analyses. Specimens examined are drawn from existing populations across northern Australia; also included for parts of this study are mummified remains from southern central South Australia and late Pleistocene subfossil specimens from south-western Western Australia. No clear-cut geographic pattern in morphological variation in M. gigas is indicated by multivariate anlysis (i.e. principal components analysis), although there is some evidence for clinal variation from univariate analysis (i.e. Scheffe's multiple-comparions procedure). Northern Australian ghost bats (with the exception of north-eastern Australian indiv~duals) tend to be smaller than their southern counterparts. Sexual dimorphism appears to be low. Independent patterns of covariation among characters are extracted by principal components analysis: cheek tooth widths cluster separately from lengths; lengths and widths of the same teeth cluster separately from those of occluding teeth; and cranial measurements cluster separately from tooth measurements. Patterns in the data suggest that the number of characters needed to be examined in future morphometric studies of the vulnerable ghost bat can be significantly reduced.

scholarly journals Phegopteris excelsior (Thelypteridaceae): A New Species of North American Tetraploid Beech Fern

2019 ◽  
Vol 27 (4) ◽  
pp. 211-218 ◽  
Author(s):  
Nikisha R. Patel ◽  
Susan Fawcett ◽  
Arthur V. Gilman
Keyword(s):  
New Species ◽  
North America ◽  
Principal Components Analysis ◽  
Principal Components ◽  
North American ◽  
Northeastern North America ◽  
Specific Rank ◽  
Components Analysis ◽  
Morphological Differences ◽  
A New Species

Since the 1970s, an apomictic tetraploid beech fern (genus Phegopteris (C. Presl) Fée) has been known in northeastern North America. Previously published isozyme data suggest that this lineage is of allopolyploid origin involving long beech fern (P. connectilis (Michx.) Watt.) but not broad beech fern (P. hexagonoptera (Michx.) Fée), as originally hypothesized. Its second progenitor remains unknown. We performed a principal components analysis of the apomict and its North American congeners to elucidate morphological differences between them. We recognize the apomictic tetraploid at specific rank as P. excelsior N. R. Patel & A. V. Gilman and provide an illustration, a range map, a list of exsiccatae, and a key to Phegopteris species of North America.

Variation in Canadian Gomphus fraternus (Odonata: Gomphidae) in relation to the recognition of subspecies manitobanus

2008 ◽  
Vol 140 (3) ◽  
pp. 327-337
Author(s):  
Paul M. Catling ◽  
Marjorie Hughes
Keyword(s):  
United States ◽  
North America ◽  
Principal Components Analysis ◽  
Principal Components ◽  
Abdominal Segment ◽  
Discrete Group ◽  
Dorsal Surface ◽  
Segment Length ◽  
Western North America ◽  
Components Analysis

AbstractSeven characters were evaluated in 146 specimens of Gomphus fraternus (Say), including both subspecies, G. f. fraternus (Say) and G. f. manitobanus Walker, to clarify their circumscription and geographic occurrence in Canada. Specimens corresponding to subspecies manitobanus were all from the Assiniboine and Red rivers and formed a discrete group in a principal components analysis, supporting their taxonomic recognition. Their distribution in Canada suggests a separation of subspecies near the boundary of the prairie ecozone in central southern Manitoba. In subspecies fraternus the extensor surfaces of the tibiae are largely black, with pale areas often lacking and rarely up to 50% of the segment length. Similarly the dorsal surface of abdominal segment 9 is largely black. If there is a pale area, it is <1 mm long. In subspecies manitobanus the extensor surfaces of the tibiae have pale markings on ≥50% of their lengths and the dorsal surface of abdominal segment 9 has a dorsal yellow spot ≥1.4 mm long. Widespread dragonflies in western North America are paler in drier climates and the increased pale colouration in the western subspecies manitobanus corresponds to this trend. Currently known only from Manitoba, subspecies manitobanus may occur in prairie habitats of the Midwestern United States, based on reports of pale individuals in that region.

Revision of the Hydroporus nigellus complex (Coleoptera: Dytiscidae) inciuding multivariate species separation

1994 ◽  
Vol 25 (1) ◽  
pp. 89-104 ◽  
Author(s):  
Anders N. Nilsson
Keyword(s):  
North America ◽  
Principal Components Analysis ◽  
Body Length ◽  
Principal Components ◽  
Nominal Species ◽  
Species Limits ◽  
Species Ranges ◽  
Penis Length ◽  
Components Analysis ◽  
Nw Europe

AbstractThe six species assigned to the Holarctic nigellus complex of Hydroporus Clairville are revised, and a key is given to the separation of males. Species limits were studied biometrically, chiefly using body length, penis length and male protarsal width. Principal components analysis was used to combine size variables taken from samples throughout species ranges. The two Holarctic species H. geniculatus Thomson, 1854, and H. nigellus Mannerheim, 1853, are separated on tarsal width, with H. nigellus being circumboreal and H. geniculatus confined to NW Europe and NW North America. Of the four other species H. semenowi Jakowlew, 1897, is Palearctic, and H. despectus Sharp, 1882, H. tartaricus LeConte, 1850, and H. tenebrosus LeConte, 1850, are Nearctic. Lectotypes are designated for the following nominal species: Hydrocoptus obscuripes Motschulsky, 1860, Hydroporus caminarius Motschulsky, 1860, Hydroporus despectus Sharp, 1882, Hydroporus eugeniae Zaitzev, 1909, Hydroporus lugubris Motschulsky, 1845, Hydroporus melancholicus Motschulsky, 1860, Hydroporus opacus Wehncke, 1871, Hydroporus pyrenaeus Wehncke, 1871, Hydroporus rusticus Sharp, 1882, Hydroporus semenowi Jakowlew, 1897, and Hydroporus tartaricus LeConte, 1850. The following new synonymies are established: Hydroporus longitarsis J. Sahlberg, 1910, and Hydroporus afflatus Scholz, 1917 = Hydroporus semenowi Jakowlew, 1897; Hydrocoptus obscuripes Motschulsky, 1860, Hydroporus pyrenaeus Wehncke, 1871, Hydroporus bungei Zaitzev, 1910, and Hydroporus tungus Zaitzev, 1910 = Hydroporus nigellus Mannerheim, 1853; Hydroporus eugeniae Zaitzev, 1909 = Hydroporus elongatulus Sturm, 1835.

Taxonomy of the Carex lenticularis complex in eastern North America

1987 ◽  
Vol 65 (4) ◽  
pp. 673-686 ◽  
Author(s):  
Lisa A. Standley
Keyword(s):  
North America ◽  
Principal Components ◽  
Chromosome Count ◽  
Morphological Data ◽  
Eastern North America ◽  
Clustering Techniques ◽  
Distribution Maps ◽  
Distinct Subgroup ◽  
Infraspecific Taxa ◽  
Components Analysis

The Carex lenticularis complex is a morphologically, anatomically, and cytologically distinct subgroup within Carex sect. Phacocystis Dumort. This complex consists of two taxa in eastern North America, C. lenticularis Michx. var. lenticularis and C. nigra (L.) Reich. Although previous treatments have recognized five infraspecific taxa within C. lenticularis var. lenticularis and two within C. nigra, analyses of morphological data using histograms, clustering techniques, and principal components analysis indicate that both species are variable but monotypic in eastern North America. Distribution maps and illustrations of both taxa are provided. A new chromosome count for C. lenticularis var. lenticularis (2n = 86) is reported, and previous records for C. nigra (2n = 84) are confirmed. Although these species are sympatric over most of the range of C. nigra, no natural hybrids are known.

Flavonoids and affinities of some North American lupines

1983 ◽  
Vol 61 (3) ◽  
pp. 708-730 ◽  
Author(s):  
K. W. Nicholls ◽  
B. A. Bohm
Keyword(s):  
United States ◽  
North America ◽  
Principal Components Analysis ◽  
Principal Components ◽  
North American ◽  
Southeastern United States ◽  
Flavonoid Glycosides ◽  
Structural Modifications ◽  
Components Analysis

Seventy-three taxa of the genus Lupinus in North America have been studied for their flavonoid constituents. In all, 56 compounds were isolated and either partially or totally characterized. Flavonoid types encountered were flavones, C-glycoflavones, isoflavones, flavonols, and, tentatively, flavanones. Further structural modifications seen were O-methylation, O-glycosylation at a variety of positions and acylation of several of the flavonoid glycosides. Principal-components analysis was performed on (i) presence–absence data of individual compounds with consideration given to relative concentrations and (ii) presence–absence of the types of flavonoid structures. Several groupings of taxa emerged from these analyses based upon the presence of unique compounds or combinations of compounds. In a number of these groups the chemical affinities paralleled morphological affinities closely. In all, 10 groupings were seen. Lupinus diffusus, a simple-leaved taxon from southeastern United States, stood apart from all groups.

Diagnoses Generated by Numerical Taxonomic Methods Applied to Standard Blood Variables

1980 ◽  
Vol 19 (04) ◽  
pp. 205-209
Author(s):  
L. A. Abbott ◽  
J. B. Mitton
Keyword(s):  
Liver Cirrhosis ◽  
Renal Disease ◽  
Principal Components Analysis ◽  
Discriminant Function ◽  
Principal Components ◽  
Discriminant Function Analysis ◽  
Chronic Renal Disease ◽  
Function Analysis ◽  
Infectious Hepatitis ◽  
Components Analysis

Data taken from the blood of 262 patients diagnosed for malabsorption, elective cholecystectomy, acute cholecystitis, infectious hepatitis, liver cirrhosis, or chronic renal disease were analyzed with three numerical taxonomy (NT) methods : cluster analysis, principal components analysis, and discriminant function analysis. Principal components analysis revealed discrete clusters of patients suffering from chronic renal disease, liver cirrhosis, and infectious hepatitis, which could be displayed by NT clustering as well as by plotting, but other disease groups were poorly defined. Sharper resolution of the same disease groups was attained by discriminant function analysis.

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