Morphological Variation and Chromosome Numbers of North American Populations of Koeleria cristata

1974 ◽  
Vol 101 (3) ◽  
pp. 124 ◽  
Author(s):  
Philip A. Robertson
Keyword(s):  
Morphological Variation ◽  
North American ◽  
Chromosome Numbers

CYTOTAXONOMY, PHYLOGENY, AND CANADIAN DISTRIBUTION OF CIRSIUM UNDULATUM AND CIRSIUM FLODMANII

1961 ◽  
Vol 39 (1) ◽  
pp. 21-33 ◽  
Author(s):  
C. Frankton ◽  
R. J. Moore
Keyword(s):  
North American ◽  
Chromosome Numbers ◽  
World Wide ◽  
North American Species ◽  
Base Number ◽  
Total Length ◽  
The World ◽  
Cirsium Undulatum

The morphology and specific differences of Cirsium undulatum (Nutt.) Spreng. and of C. flodmanii (Rydb.) Arthur are described and their Canadian distributions are reported in detail. The chromosome numbers are C. undulatum f. undulatum and f. album Farwell, 2n = 26; C. flodmanii f. flodmanii and f. albiflorum D. Löve, 2n = 22. The origin of four North American species of Cirsium that do not follow the world-wide base number 17 is discussed; it is postulated that reduction in number has occurred by translocations. The chromosomes of species with reduced numbers are larger than those of the unreduced species but the total length of the chromosomes of both groups is approximately the same.

Chromosome numbers and sexual compatibility in North America of Rorippa sylvestris (Cruciferae)

1984 ◽  
Vol 62 (3) ◽  
pp. 575-580 ◽  
Author(s):  
Gerald A. Mulligan ◽  
Derek B. Munro
Keyword(s):  
North America ◽  
North American ◽  
Chromosome Numbers ◽  
Interspecific Hybrid ◽  
Field Observations ◽  
Sexual Compatibility ◽  
Intraspecific Crossing

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.

CHROMOSOME NUMBERS FOR NORTH AMERICAN EUPHORBIACEAE

1975 ◽  
Vol 62 (5) ◽  
pp. 494-500 ◽  
Author(s):  
Lowell E. Urbatsch ◽  
John D. Bacon ◽  
Ronald L. Hartman ◽  
Marshall C. Johnston ◽  
Thomas J. Watson ◽  
...  
Keyword(s):  
North American ◽  
Chromosome Numbers

Taxonomic Recognition of Ammophila champlainensis and Morphological Variation in Northeastern North American Ammophila (Poaceae)

Rhodora ◽  
2008 ◽  
Vol 110 (942) ◽  
pp. 129-156 ◽  
Author(s):  
Mireille B. Delisle-Oldham ◽  
Michael J. Oldham ◽  
Paul M. Catling
Keyword(s):  
Morphological Variation ◽  
North American

Chromosome numbers of 15 North American bumble bee species (Hymenoptera, Apidae, Bombini)

1983 ◽  
Vol 25 (1) ◽  
pp. 26-29
Author(s):  
Robin E. Owen
Keyword(s):  
Chromosome Number ◽  
North American ◽  
Chromosome Numbers ◽  
Bumble Bees ◽  
Bumble Bee ◽  
Morphological Divergence ◽  
Chromosome Counts ◽  
Monophyletic Origin ◽  
The Social

Chromosome counts were obtained for 14 Bombus Latr. species (the social bumble bees) belonging to four subgenera and for one Psithyrus Lep. species (the social parasitic bumble bees). In Bombus the haploid numbers were consistent within each subgenus and there was variation between subgenera; the subgenera Bombus s.s. and Pyrobombus have n = 18, while Separatobombus and Cullumanobombus have n = 19. Thus considerable morphological divergence between subgenera is often, but not always, paralleled by divergence in chromosome number. Psithyrus ashtoni has n = 25, higher than all Bombus species yet examined. This provides support for the monophyletic origin of Psithyrus, but the high n is not expected if eusociality selects for increase in chromosome number.

The systematics of Ranunculus gmelinii and R. hyperboreus in North America

1974 ◽  
Vol 52 (7) ◽  
pp. 1713-1722 ◽  
Author(s):  
Peter J. Scott
Keyword(s):  
Phenotypic Plasticity ◽  
North America ◽  
Morphological Variation ◽  
North American ◽  
Growth Conditions ◽  
Controlled Growth ◽  
The North ◽  
Representative Material

A consideration of the taxonomy of Ranunculus gmelinii DC. and R. hyperboreus Rottb. is presented. The role of phenotypic plasticity is indicated as a factor contributing to the range of morphological variation in these species and to the confusion found in their taxonomy. The present work, by a reexamination of representative material collected throughout the North American range of the species, and the use of controlled growth conditions, has suggested new limits for the species. This has resulted in modifications of the descriptions of the species and (or) the reduction of taxa to synonymy.Ranunculus hyperboreus Rottb. var. turquetilianus Polunin has been made a synonym of R. gmelinii DC.; R. natans C.A. Mey. var. intertextus (Greene) L. Benson has been made a synonym of R. hyperboreus Rottb.

The chromosome numbers of five North American and European leech species

1987 ◽  
Vol 65 (3) ◽  
pp. 681-684 ◽  
Author(s):  
Ronald W. Davies ◽  
R. N. Singhal
Keyword(s):  
Chromosome Number ◽  
North American ◽  
Chromosome Numbers ◽  
Chromosome Evolution ◽  
Chromosome Counts ◽  
Prophase I ◽  
Metaphase I

Chromosome counts were obtained for four glossiphoniid species belonging to three genera (Glossiphonia, Theromyzon, Placobdella) and for one erpobdellid species (Dina lineata) of freshwater leeches. Theromyzon rude, which has a Palaearctic distribution, had seven bivalents at prophase I and metaphase I, while the Holarctic T. tessulatum had eight bivalents, giving diploid chromosome numbers of 14 and 16, respectively. Placobdella papillifera from Alberta had a chromosome number of 2n = 24 and Glossiphonia complanata from Alberta and England had chromosome counts of 2n = 28. At prophase I and metaphase I nine bivalents occurred in the majority of the nuclei of Dina lineata. These findings are discussed in relation to the chromosome evolution and phylogenetic schemes proposed by previous authors.

scholarly journals Taxonomic Revision of the Genus Lactifluus (Russulales, Basidiomycota) of South Korea

2021 ◽  
Author(s):  
Hyun Lee ◽  
Komsit Wissitrassameewong ◽  
Myung Soo Park ◽  
Jonathan J. Fong ◽  
Annemieke Verbeken ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Morphological Variation ◽  
North American ◽  
Species Delimitation ◽  
Taxonomic Revision ◽  
Molecular Data ◽  
Similar Species ◽  
Cryptic Diversity ◽  
Intraspecific Morphological Variation

Abstract Lactifluus (Pers.) Roussel is an ectomycorrhizal genus that was recently recognized to be distinct from the genus Lactarius. To date, 216 Lactifluus species have been reported worldwide. Misidentification of Lactifluus species is common because of intraspecific morphological variation, cryptic diversity, and the limited number of taxonomic keys available. Molecular data are indispensable for species delimitation; a multilocus phylogenetic analysis showed that most Asian Lactifluus species are not conspecific with morphologically similar species present on other continents. In particular, Korea has misused European and North American Lactifluus names. In this study, we evaluated the taxonomy of Lactifluus in Korea using both morphological and multilocus molecular (ITS, nrLSU, rpb1, and rpb2) data. We examined 199 Lactifluus specimens collected between 1980 and 2016, and a total of 24 species across the four Lactifluus subgenera were identified. All Korean species are distinct and clearly separated from European and North American species. Five taxa corresponded to previously described species from Asia and the remaining 19 taxa are confirmed as new species. Herein, we provide keys to the Korean Lactifluus species within their subgenera, molecular phylogenies, a summary of diversity, and detailed description of the new species.

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