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.

Taxonomic revision of the Carex stricta (Cyperaceae) complex in eastern North America

1989 ◽  
Vol 67 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Lisa A. Standley
Keyword(s):  
North America ◽  
Chromosome Numbers ◽  
Taxonomic Revision ◽  
Distinct Species ◽  
North American Species ◽  
Eastern North America ◽  
Distribution Maps ◽  
Carex Stricta ◽  
Morphological Studies ◽  
Infraspecific Taxa

Morphological studies of the Carex stricta complex confirm hypotheses based on chromosome numbers that there are three distinct species in eastern North America, Carex stricta, C. emoryi, and C. haydenii, but they do not indicate the existence of any distinct infraspecific taxa. These species are compared phenetically with all other North American species of section Phacocystis. Results indicate that the three species examined here do not form a closely related subgroup within the section as suggested by previous authors. Distribution maps, descriptions, and synonomy are provided for these species, and a complete key to the species of section Phacocystis in eastern North America is given.

A taxonomic study of Stipa nelsonii (Poaceae) with a key distinguishing it from related taxa in western North America

1979 ◽  
Vol 57 (22) ◽  
pp. 2539-2553 ◽  
Author(s):  
Mary E. Barkworth ◽  
J. McNeill ◽  
Jack Maze
Keyword(s):  
North America ◽  
Weighting Function ◽  
The United States ◽  
Morphological Data ◽  
Numerical Analyses ◽  
Western North America ◽  
Distribution Maps ◽  
Infraspecific Taxa ◽  
Character Weighting ◽  
Intermountain Region

Stipa nelsonii, more commonly but incorrectly known as S. Columbiana, is a wide ranging species of western North America, characterized by a short, pubescent palea and a hirtellous awn. Initial numerical analyses, using unweighted morphological data, suggested that three infraspecific taxa existed but with different methods of analysis there was a disturbing instability in the placement of certain operational taxonomic units (OTUs), including those based on the holotype of S. williamsii. Because replicate OTUs were incorporated in the sample, a character weighting, based on the relative constancy of character states within replicate pairs, was applied. The particular weighting function adopted utilized the added component of variance between groups, i.e., between the replicate pairs. Numerical analyses based on the weighted data proved to be stable with respect to all the OTUs. They suggested recognition of three infraspecific taxa. Keys to these taxa were devised and applied to about 400 additional specimens allowing the geographical and ecological distributions of the suggested taxa to be examined. The combined morphological and distributional studies suggest that S. nelsonii comprises two subspecies: subsp. nelsonii and subsp. dorei. Two varieties can be recognized in subsp. nelsonii: var. nelsonii centered in the intermountain region of the United States and var. longiaristata centered in eastern Washington. The range of subsp. dorei extends from southern Yukon to California and eastward to the Saskatchewan–Manitoba border. A key to the infraspecific taxa of S. nelsonii and to related taxa of western North America is included, as well as descriptions and distribution maps of the infraspecific taxa recognized in S. nelsonii.

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.

Figuring out the figs: the Ficus obliqua-Ficus rubiginosa Complex (Moraceae: Urostigma sect. Malvanthera)

2001 ◽  
Vol 14 (1) ◽  
pp. 133 ◽  
Author(s):  
Dale J. Dixon ◽  
B. R. Jackes ◽  
L. M. Bielig
Keyword(s):  
Multidimensional Scaling ◽  
Phenetic Analysis ◽  
Morphometric Characters ◽  
Clustering Techniques ◽  
Distribution Maps ◽  
Infraspecific Taxa

A revision of the Ficus obliqua—F. rubiginosa complex (Moraceae: Urostigma sect. Malvanthera Corner) is presented. A phenetic analysis of morphometric characters using clustering techniques and multidimensional scaling was used to identify the taxa in this complex. Three taxa are recognised, F. obliqua G.Forst., F. rubiginosa Desf. ex Vent. f. rubiginosa and F. rubiginosa f. glabrescens (F.M.Bailey) D.J.Dixon. Each taxon is redescribed. The epithet glabrescens of F. rubiginosa f. glabrescens is resurrected with a change in status. The data from the pollinator wasps strongly supports the taxonomy, with F. obliqua pollinated by Pleistodontes greenwoodi (Grandi) and F. rubiginosa sens lat. pollinated by P. imperialis Saunders. A key to the species and infraspecific taxa of F. rubiginosa as well as notes and distribution maps are provided for both species.

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.

Systematics of North American Petasites (Asteraceae: Senecioneae). I. Morphometric analyses

1998 ◽  
Vol 76 (1) ◽  
pp. 23-36 ◽  
Author(s):  
Donna M Cherniawsky ◽  
Randall J Bayer
Keyword(s):  
North America ◽  
Principal Components ◽  
North American ◽  
Complex Form ◽  
Morphological Differentiation ◽  
Classification Systems ◽  
Morphological Data ◽  
Morphometric Analyses ◽  
Cohesive Group ◽  
Reproductive Characters

Petasites Mill. (Asteraceae: Senecioneae) is a taxonomically difficult genus of polygamodioecious, perennial clonal herbs distributed across Canada, Alaska, and the northern contiguous United States. The taxonomic confusion surrounding the genus is reflected in the ambiguity of the various classification systems currently used. As many as ten species and as few as two species have been recognized (Petasites sagittatus (Banks ex Pursh) Gray and Petasites frigidus (L.) Fries with three varieties), in addition to one hybrid taxon. To determine if discrete groups could be recognized according to a combination of vegetative and (or) reproductive characters and thereby clarify the phenetic relationships among the taxa of Petasites, morphological data were subjected to principal components and discriminant analyses. Particular emphasis was placed on P. frigidus var. frigidus, P. frigidus var. nivalis sensu Bogle, and the purported hybrid between these taxa, which exhibits an intermediate morphology (the frigidus complex). Additionally, the specific status of P. sagittatus was investigated. Evidence obtained from multivariate morphometric analyses indicates that North American Petasites is comprised of four closely related polymorphic entities. While morphological variation among different taxa of Petasites is continuous for most reproductive characters, leaf characters were determined to be the most taxonomically discriminating. The entities of the frigidus complex form a cohesive group somewhat distinct from the other taxa. The morphological differentiation between P. sagittatus and other taxa of Petasites is not considered sufficient to warrant recognition of specific status. Therefore, we recommend that only one polymorphic species of Petasites in North America be recognized (P. frigidus with three varieties) in addition to one hybrid taxon originating from a cross between two of the varieties. Key words: Petasites, Asteraceae, North America, systematics, principal components analysis, discriminant analysis.

A comparison of the soluble seed proteins of certain Acer species

1971 ◽  
Vol 49 (11) ◽  
pp. 1951-1957 ◽  
Author(s):  
Theodore T. Ziegenfus ◽  
Roy B. Clarkson
Keyword(s):  
North America ◽  
Seed Proteins ◽  
Double Diffusion ◽  
Disc Electrophoresis ◽  
High Protein ◽  
The Other ◽  
Morphological Data ◽  
Eastern North America ◽  
Low Protein

Seed proteins of seven taxa of Acer native to eastern North America were obtained by extraction in 2.5% saline buffer, pH 7.0. These were investigated using the techniques of polyacrylamide disc electrophoresis, immunoelectrophoresis, and double diffusion. Groupings indicated by our protein data were compared with groupings by other researchers based on morphological data. The members of the section Saccharina, A. saccharum subsp. saccharum, A. s. subsp. nigrum and A. s. subsp. floridanum, were found to have close protein similarity. A. negundo, thought by several workers to be the most distinct of the maples, was found to have relatively high protein similarity with the members of the section Saccharina. A. rubrum and A. spicatum were shown to have the least protein similarity to the other taxa investigated. There is low protein similarity between these two taxa, however, indicating they are divergent. The traditional placement of A. rubrum and A. saccharinum in the same section was supported by the relatively high protein similarity of these taxa. Data obtained by serological techniques and polyacrylamide disc electrophoresis were found to be complementary. However, polyacrylamide disc electrophoresis was more sensitive in detecting the protein differences among the taxa investigated.

scholarly journals Xerocomellus (Boletaceae) in western North America

2020 ◽  
Vol 6 (1) ◽  
pp. 265-288
Author(s):  
J.L. Frank ◽  
N. Siegel ◽  
C.F. Schwarz ◽  
B. Araki ◽  
E.C. Vellinga
Keyword(s):  
North America ◽  
Morphological Variability ◽  
Morphological Data ◽  
Eastern North America ◽  
New Combinations ◽  
Western North America ◽  
Key To Species ◽  
Dichotomous Key ◽  
Species Complexes ◽  
Three New Species

Understanding diversity in the genus Xerocomellus in western North America has been obscured by morphological variability, widespread use of species epithets typified by specimens from Europe and eastern North America, misunderstood phylogenetic relationships, and species complexes. We collected extensively and used genetic and morphological data to establish the occurrence of ten Xerocomellus species in western North America. We generated ITS sequences from five type collections and from vouchered representative collections to clarify our understanding of existing species concepts. We describe three new species (Xerocomellus atropurpureus, X. diffractus, and X. salicicola) and propose two new combinations (X. amylosporus and X. mendocinensis), transfer Boletus coccyginus to Hortiboletus, and provide a dichotomous key to species of Xerocomellus in western North America.

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