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.

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.

Morphometric analysis of western North American Antennaria (Asteraceae: Inuleae). I. Sexual species of sections Alpinae, Dioicae, and Plantaginifoliae

1987 ◽  
Vol 65 (11) ◽  
pp. 2389-2395 ◽  
Author(s):  
Randall J. Bayer
Keyword(s):  
Morphometric Analysis ◽  
Principal Components ◽  
North American ◽  
Cluster Analyses ◽  
Sexual Species ◽  
Morphometric Analyses

Eight sexual species of Antennaria Gaertner from sections Alpinae, Dioicae, and Plantaginifoliae have been recognized based on morphometric analyses such as principal components and cluster analyses. These taxa include A. aromatica Evert (Alpinae), A. corymbosa Nelson (Dioicae), A. marginata Greene (Dioicae), A. media Greene (Alpinae), A. microphylla Rydb. (Dioicae), A. racemosa Hook. (Plantaginifoliae), A. rosulata Rydb. (Dioicae), and A. umbrinella Rydb. (Dioicae). Taxa having both diploid and polyploid cytotypes are A. aromatica, A. marginata, A. media, A. microphylla, and A. umbrinella, whereas A. corymbosa, A. racemosa, and A. rosulata are strictly sexually reproducing diploids.

Taxonomic revision of the genus Tetraglochin (Rosaceae, Rosoideae) and morphometric analysis of its species

Phytotaxa ◽  
2017 ◽  
Vol 296 (3) ◽  
pp. 201 ◽  
Author(s):  
ANA M. CIALDELLA ◽  
CAROLINA L. POMETTI
Keyword(s):  
Discriminant Analysis ◽  
Morphological Differentiation ◽  
Taxonomic Revision ◽  
Canonical Discriminant Analysis ◽  
New Combination ◽  
The Andes ◽  
General Terms ◽  
Morphometric Analyses ◽  
Almost All ◽  
Reproductive Characters

Tetraglochin is a small genus distributed along the Andes from Perú to southern Argentina and central Chile, belonging to the family Rosaceae. Systematic studies in Tetraglochin are scarce, and circumscription of some members of this genus is controversial. In order to evaluate the degree of morphological differentiation between the species of this genus, we performed morphometric analyses using multivariate methods (non parametric ANOVA, phenetic analysis and canonical discriminant analysis) including those specimens with intermediate characteristics between T. alata and T. ameghinoi. The phenogram obtained showed two principal clusters; this picture suggested a clear grouping of the specimens of T. alata, T. ameghinoi, T. aff. alata and T. andina. In the canonical discriminant analysis five groups were found and in general terms all individuals of T. alata, T. aff. alata and T. ameghinoi were grouped together. When multivariate analyses were applied almost all specimens could be correctly assigned to its species. However, specimens of T. alata, T. aff. alata and T. ameghinoi , were not well discriminated. Following recent phylogenetic results on the genus, and morphometric analyses perfomed herein for the first time, we present an updated taxonomic revision of Tetraglochin, based on exomorphological, vegetative and reproductive characters, including a key to identify species and varieties, their associated synonymy, full descriptions, geographical distribution and illustrations. As result, a new combination, T. alata var. ameghinoi is proposed, T. alata var. patagonica is reduced to synonymy of T. alata var. alata, and T. paucijugata and T. tragacantha are reduced to synonymy of T. cristata. Lectotypes for Margyricarpus acanthocarpus, Tetraglochin acanthocarpa var. lasiocarpa, var. dasycarpa, var. macropoda and var. lejocarpa are designated. One species, Tetraglochin buxifolia is excluded from the genus.

Circumscription of species of Hodophilus (Clavariaceae, Agaricales) in North America with naphthalene odours

Botany ◽  
2016 ◽  
Vol 94 (10) ◽  
pp. 941-956 ◽  
Author(s):  
Slavomír Adamčík ◽  
Brian P. Looney ◽  
Joshua M. Birkebak ◽  
Soňa Jančovičová ◽  
Katarína Adamčíková ◽  
...  
Keyword(s):  
North America ◽  
North American ◽  
Phylogenetic Analyses ◽  
Distinct Species ◽  
Morphological Type ◽  
Morphological Data ◽  
Western North America ◽  
Phylogenetic Species ◽  
New Approach ◽  
Previously Treated

Five North American Hodophilus species with naphthalene-like odours are now recognized based on sequence and (or) morphological data and molecular annotation of type collections. Two well-supported eastern North American species do not match any of the studied types and are described here as new: Hodophilus hesleri and Hodophilus smithii. The previously described Hodophilus paupertinus is found to represent an autonomous species and appears restricted to western North America. Hodophilus subfuscescens is found to be an independent lineage in eastern North America. A morphological type study of Hodophilus peckianus shows that it is a distinct species and not represented among recent collections. Multilocus phylogenetic analyses of European and North American material of species with naphthalene odours reveal no species with transatlantic distributions. Overall, Hodophilus comprises two superclades (the Hodophilus foetens superclade and the Hodophilus micaceus superclade) and 16 terminal clades that correspond to phylogenetic species. This study introduces a new approach for morphological delimitation of agaricoid Clavariaceae combining shape and dimensions of particular elements in the pileipellis and caulocystidia. All previously described taxa included in this study, which were previously treated in the genera Hygrophorus, Camarophyllopsis, or Hygrotrama, are formally transferred to Hodophilus.

Lucilia bufonivora, Not Lucilia silvarum (Diptera: Calliphoridae), Causes Myiasis in Anurans in North America With Notes About Lucilia elongata and Lucilia thatuna

2020 ◽  
Author(s):  
T L Whitworth ◽  
Matthew G Bolek ◽  
G Arias-Robledo
Keyword(s):  
Life History ◽  
North America ◽  
North American ◽  
American Studies ◽  
Morphological Differentiation ◽  
Genetic Distances ◽  
Morphological Evidence ◽  
Adult Males ◽  
Adult Females ◽  
Palearctic Region

Abstract In North America, until recently, all cases of anuran myiasis were attributed to Lucilia silvarum (Meigen) or Lucilia elongata Shannon. The latter species is exceedingly rare and its life history is unknown, but L. silvarum is common and was thought to be capable of being either parasitic or saprophytic in North America. Until recently, the anuran parasite Lucilia bufonivora Moniez was thought to be strictly Palearctic, but a study in 2014 has determined this species is established throughout southern Canada. In 2019, a study demonstrated, with molecular and morphological evidence, that two adult flies formerly identified as L. silvarum and reared from amphibian myiasis cases from Canada, are actually L. bufonivora. Although the mentioned study detected relatively high genetic distances with European L. bufonivora, the lack of evident morphological differentiation suggest that they are the same species. The current study examined 12 adult males and eleven adult females morphologically from three additional North American studies. Specimens were examined which had been identified as L. silvarum or L. elongata, and they all proved to be L. bufonivora. We now suspect L. silvarum is strictly saprophagous in North America like they are in the Palearctic Region. We also provide evidence that the pattern of myiasis differs between European and North American specimens.

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.

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