The taxonomy of the Carex rosea group (section Phaestoglochin) in Canada

1984 ◽  
Vol 62 (10) ◽  
pp. 2058-2073 ◽  
Author(s):  
J. M. Webber ◽  
P. W. Ball

The Carex rosea group, part of section Phaestoglochin, consists of four species, three of which, C. appalachica Webber & Ball, C. rosea Schkuhr ex Willd., and C. radiata (Wahlenberg) Small, occur in Canada. It is shown that some characters used to separate the species, i.e., perigynium length, colouration of the orifice of the beak, number of perigynia per spike, and length of the lowest infructescence bract, are unreliable. Other characters, such as the widths of the broadest leaves and fertile culms, width and degree of coiling of the stigmas, shape of the perigynium base, and position of the achene within the perigynium, were found to afford a reliable separation of the species. Analysis of mixed populations of C. rosea, C. radiata, and C. appalachica suggests that hybridization does not occur. The chromosome numbers of the three Canadian species were found to be as follows: C. rosea, n = 26; C. radiata, n = 29; and C. appalachica, n = 26. Distribution maps of the three species in North America are also given.

1989 ◽  
Vol 67 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Lisa A. Standley

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.


1980 ◽  
Vol 112 (S112) ◽  
pp. 1-92 ◽  
Author(s):  
D.D. Munroe ◽  
Ray F. Smith

AbstractThe systematics of Acalymma sensu stricto of North America including Mexico are revised. Acalymma sensu stricto is defined and distinguished from the other species groups of Acalymma. Sixteen species are discussed including four new species: A. blomorum, A. palomarense, A. invenustum, and A. luridifrons all from Mexico. Three new subspecies of A. blandulum (LeConte) are described: blandulum (LeConte) new status, nigriventre, and yucatanense. Acalymma coruscum costaricense Bechyné is placed as a synonym of A. innubum (Fabricius). Keys are presented to all species and subspecies. Habitus and male genitalia drawings are given for all species and distribution maps are given where appropriate.


1983 ◽  
Vol 61 (12) ◽  
pp. 3140-3163 ◽  
Author(s):  
L. Kott ◽  
D. M. Britton

Taxonomy of Isoetes L. largely rests on megaspore and microspore wall ornamentation and spore size. These characters have been reevaluated and the range of their variability is described (SEM photographs). Eight species of Isoetes are recognized for northeastern North America: I. macrospora, I. hieroglyphica, I. tuckermanii, I. riparia, I. acadiensis, I. echinospora, I. eatonii, and I. engelmannii. Each species is provided with a revised list of synonyms, description, ecological notes, representative specimens, and distribution maps. A key to species is provided.


HortScience ◽  
2018 ◽  
Vol 53 (5) ◽  
pp. 620-623
Author(s):  
Thomas G. Ranney ◽  
Connor F. Ryan ◽  
Lauren E. Deans ◽  
Nathan P. Lynch

Illicium is an ancient genus and member of the earliest diverging angiosperms known as the Amborellales, Nymphaeales, and Austrobaileyales (ANA) grade. These adaptable, broadleaf evergreen shrubs, including ≈40 species distributed throughout Asia and North America, are valued for diverse culinary, medicinal, and ornamental applications. The study of cytogenetics of Illicium can clarify various discrepancies and further elucidate chromosome numbers, ploidy, and chromosome and genome size evolution in this basal angiosperm lineage and provide basic information to guide plant breeding and improvement programs. The objectives of this study were to use flow cytometry and traditional cytology to determine chromosome numbers, ploidy levels, and relative genome sizes of cultivated Illicium. Of the 29 taxa sampled, including ≈11 species and one hybrid, 2C DNA contents ranged from 24.5 pg for Illicium lanceolatum to 27.9 pg for Illicium aff. majus. The genome sizes of Illicium species are considerably higher than other ANA grade lineages indicating that Illicium went through considerable genome expansion compared with sister lineages. The New World sect. Cymbostemon had a slightly lower mean 2C genome size of 25.1 pg compared with the Old World sect. Illicium at 25.9 pg, providing further support for recognizing these taxonomic sections. All taxa appeared to be diploid and 2n = 2x = 28, except for Illicium floridanum and Illicium mexicanum which were found to be 2n = 2x = 26, most likely resulting from dysploid reduction after divergence into North America. The base chromosome number of x = 14 for most Illicium species suggests that Illicium are ancient paleotetraploids that underwent a whole genome duplication derived from an ancestral base of x = 7. Information on cytogenetics, coupled with phylogenetic analyses, identifies some limitations, but also considerable potential for the development of plant breeding and improvement programs with this genus.


Zootaxa ◽  
2018 ◽  
Vol 4457 (3) ◽  
pp. 444
Author(s):  
THOMAS AUSTIN ◽  
DANIEL HEFFERN ◽  
ROBERT GEMMILL ◽  
BRIAN RABER ◽  
MIKE QUINN

New distributional records, new larval host records, various collecting notes, and observations are reported for the North American species of the tribe Agallissini LeConte, 1873 (Coleoptera: Cerambycidae: Cerambycinae): Agallissus lepturoides (Duponchel & Chevrolat, 1841), Osmopleura chamaeropis (Horn, 1893), and Zagymnus clerinus (LeConte, 1873). The species are illustrated and distribution maps are provided.


Author(s):  
V. P. Hayova

Abstract A description is provided for Valsa sordida. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. DISEASE: Valsa sordida is usually associated with Valsa canker of poplar twigs. Wounded trees, and trees injured by insects or attacked by other pathogens are more susceptible to infection. Development of Valsa canker is affected by environmental stress (Guyon, 1996; Tao et al., 1984). Poplar canker caused by V. sordida has been studied in different countries (CMI Distribution Maps of Plant Diseases, 1977; Worrall, 1983; Wang et al., 1981) The fungus can be often found in declining poplar stands together with another pathogen of poplar trees, Leucostoma niveum. Valsa sordida may also cause necrosis of willow twigs. HOSTS: Populus spp., Salix spp. and, more rarely, other woody angiosperms. GEOGRAPHICAL DISTRIBUTION: Africa: Morocco. Asia: Armenia, Azerbaijan, China, Republic of Georgia, India, Iran, Iraq, Israel, Japan. Kazakhstan, Korea, Russia (Tatarstan), Turkey, Turkmenia, Uzbekistan. Australasia: Australia (Victoria), New Zealand. Europe: Austria, Belgium, Bulgaria, Czech Republic, Denmark, Estonia, France, Germany, Greece, Ireland, Italy, Netherlands, Norway, Poland, Portugal, Rumania, Russia, Slovakia, Sweden, Switzerland, UK, Ukraine, former Yugoslavia. North America: Canada (Alberta, British Columbia, Nova Scotia, Ontario, Québec, Saskatchewan). USA (California, Colorado, Michigan, Minnesota). South America: Chile. TRANSMISSION: Both conidia and ascospores are air-borne, especially under humid conditions. Yellow or orange exudation of conidia from conidiomata can be often seen after rain.


1984 ◽  
Vol 62 (3) ◽  
pp. 575-580 ◽  
Author(s):  
Gerald A. Mulligan ◽  
Derek B. Munro

Tetraploid (2n = 32), pentaploid (2n = 40), and hexaploid (2n = 48) plants of Rorippa sylvestris (L.) Besser (Cruciferae) and a natural pentaploid (2n = 40) interspecific hybrid, R. sylvestris × R. palustris (L.) Besser, are recorded for North America. These counts are compared with published information on European plants. Tetraploids are most common in Europe (68 vs. 20%), whereas hexaploids are most common in North America (65 vs. 29%). Although self-incompatible R. sylvestris rarely sets seed in nature, indicating that plants within most sites are genetically the same clone, intraspecific crossing data, chromosome information, and field observations indicate that North American R. sylvestris results from the vegetative introduction of many different genotypes.


Haseltonia ◽  
2009 ◽  
Vol 15 ◽  
pp. 117-134 ◽  
Author(s):  
Marc A Baker ◽  
Jon P Rebman ◽  
Bruce D Parfitt ◽  
Donald J Pinkava ◽  
Allan D Zimmerman

1975 ◽  
Vol 53 (15) ◽  
pp. 1491-1522 ◽  
Author(s):  
Robert D. Dorn

Twelve North American species of the section Cordatae of the genus Salix (willows) were studied to clarify their taxonomy. The sections Adenophyllae (Commutatae) and Wolfianae are included here in section Cordatae. Characteristics of the epidermal cells and pollen grains were of no taxonomic value. Chromosome counts were obtained for 6 of the 12 species. One other species had been counted earlier. There are three diploid species, two tetraploids, and a hexaploid. One other species (?) has both diploid and tetraploid populations. Flavonoid chemistry of the leaves was the most important and constant characteristic. Each species has a consistent combination of compounds different from those of all other species of the section. Cytology, chemistry, morphology, and distribution were well correlated. Keys to pistillate material, synonymy, descriptions, distribution maps, and representative specimens are included. Three new species are described and one varietal transfer is made.


1977 ◽  
Vol 104 (2) ◽  
pp. 105 ◽  
Author(s):  
Donald J. Pinkava ◽  
Lyle A. McGill ◽  
Timothy Reeves

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