BRYOPHYTES OF THE CYPRESS HILLS PROVINCIAL PARKS, ALBERTA AND SASKATCHEWAN

1962 ◽  
Vol 40 (4) ◽  
pp. 573-587 ◽  
Author(s):  
C. D. Bird
Keyword(s):  
Distribution Pattern ◽  
North American ◽  
Special Interest ◽  
Chromosome Counts ◽  
Provincial Parks

One hundred mosses and seven liverworts are reported from the Cypress Hills of southwestern Alberta and southeastern Saskatchewan. Included are 11 bryophytes not previously reported from Saskatchewan and 6 new to Alberta. Of special interest was the discovery of Scapania carinthiaca, known previously from two North American stations and a few in Europe and Siberia. Also interesting was the collection of Dicranum drummondii and Mnium drummondii, both of which are seldom encountered and are restricted to a central North American distribution pattern. Chromosome counts were made from material of Atrichum undulatum var. altecristatum (n = 7), Atrichum selwynii (n = 7), and Plagiothecium turfaceum (n = 11). The ecology and elements of the area are discussed. A montane element of 9.1% was found to exist in the moss flora.

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.

Taxonomic studies on the genus Atrichum in North America

1969 ◽  
Vol 47 (3) ◽  
pp. 353-368 ◽  
Author(s):  
Robert R. Ireland
Keyword(s):  
United States ◽  
North America ◽  
North American ◽  
Distinct Species ◽  
The United States ◽  
Morphological Characters ◽  
Taxonomic Study ◽  
Chromosome Counts ◽  
The Status ◽  
Taxonomic Studies

A taxonomic study was made of several North American taxa in the genus Atrichum. The primary emphasis was on the Canadian taxa and a key to the six species (A. altecristatum, A. angustatum, A. crispum, A. oerstedianum, A. selwynii, A. undulatum) and one variety (A. undulatum var. gracilisetum) of the country is presented. Atrichum oerstedianum, which has been confused with A. undulatum, is added to the moss flora of the United States and Canada. The distribution of A. crispum is clarified and a detailed study of the species revealed new morphological characters that are useful to distinguish it. A variety of A. undulatum, the var. altecristatum, is raised to the rank of a species and morphological and distributional data are given to support the status of A. selwynii as a distinct species. The first chromosome counts are reported for A. selwynii (n = 7) and A. altecristatum (n = 14). Detailed descriptions are provided for A. altecristatum, A. crispum, A. oerstedianum, and A. selwynii.

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.

A STUDY OF VARIABILITY IN CRESTED WHEATGRASS

1955 ◽  
Vol 33 (6) ◽  
pp. 534-546 ◽  
Author(s):  
R. P. Knowles
Keyword(s):  
North American ◽  
Agropyron Cristatum ◽  
Tetraploid Species ◽  
Root Tips ◽  
Chromosome Counts ◽  
Crested Wheatgrass ◽  
Fertile Hybrids ◽  
Accessory Chromosomes ◽  
Sterile Hybrids

Thirty-one strains of crested wheatgrass from European and North American sources were assigned to six morphological forms. These forms showed affinities to the species Agropyron cristatum (L.) Gaertn., A. desertorum (Fisch.) Roem. & Schult., A. sibiricum (Willd.) P.B., A. fragils (Roth.) Nevski, A. michnoi Roshev., and A. imbricatum (M.B.) Roem. & Schult. Typical plants, spikes, glumes, and seeds of the six forms were illustrated. Eight strains of A. cristatum were diploid (2n = 14) and two strains were tetraploid (2n = 28). Strains of all other forms were tetraploid. Chromosome counts of root tips indicated no aneuploids in 71 diploid plants and one aneuploid (2n = 29) in 96 tetraploid plants. Meiotic observations, however, indicated accessory chromosomes in 14 of 43 tetraploid plants. Diploid forms of A. cristatum crossed sparingly with tetraploid species to form sterile hybrids. All tetraploid species were interfertile and formed fertile hybrids. Most desirable strains agronomically were of the species A. cristatum, A. desertorum, and A. imbricatum. Most vigorous hybrids were sterile plants from crosses of A. desertorum and A. cristatum.

The Cirsium arizonicum complex of the southwestern United States

1974 ◽  
Vol 52 (3) ◽  
pp. 543-551 ◽  
Author(s):  
R. J. Moore ◽  
C. Frankton
Keyword(s):  
United States ◽  
New Species ◽  
North American ◽  
North American Species ◽  
Southwestern United States ◽  
Chromosome Counts ◽  
Natural Group ◽  
Three New Species

The morphology, cytology, distribution, and phylogeny of eight species of the southwestern United States closely related to Cirsium arizonicum are considered. These species form a natural group distinguished from other North American species of Cirsium by a short stigma (1–3 mm) and long corolla lobes (10–20 mm) which are longer than the corolla throat. Three new species described are C. chellyense, C. chuskaense, and C. navajoense. Original chromosome counts are presented for C. nidulum, 2n = 34; C. rothrockii, 2n = 30; C. arizonicum, n = 15; C. chuskaense, 2n = 34; and C. arizonicum × nidulum, 2n = 32, 34.

NOTES ON THE DISTRIBUTION AND HOST PLANTS OF SOME NORTH AMERICAN MIRIDAE (HEMIPTERA)

1927 ◽  
Vol 59 (2) ◽  
pp. 34-44 ◽  
Author(s):  
Harry H. Knight
Keyword(s):  
North American ◽  
Special Interest ◽  
Host Plants ◽  
The Past ◽  
Host Relationships

The following notes have accumulated while collecting and naming species of Miridae during the past ten years. The records are chiefly of species where the distribution is new or of special interest, or to give data on host relationships. I wish to take this occasion to acknowledge the assistance I have received from several botanists who have from time to time determined plants for me.

Schistidium relictum (Grimmiaceae, Bryophyta), a new moss species from Northwest North America and Siberia

Phytotaxa ◽  
2017 ◽  
Vol 299 (2) ◽  
pp. 234 ◽  
Author(s):  
TERRY T. MCINTOSH ◽  
HANS H. BLOM ◽  
OXANA I. KUZNETSOVA ◽  
ELENA A. IGNATOVA
Keyword(s):  
North America ◽  
Distribution Pattern ◽  
North American ◽  
Disjunct Distribution ◽  
Pleistocene Glaciations ◽  
Moss Species ◽  
Molecular Studies ◽  
Siberian Species

Schistidium relictum is described as a new northwest North American and Siberian species of moss. Important distinguishing characters include dull, nearly black plants, with stems densely and evenly foliated, weakly spreading leaves that usually lack awns, and the mostly 1-stratose distal leaf laminae with 2(–3) -stratose margins. The species has a remarkable disjunct distribution pattern with most of the sites where it has been found having been unglaciated during the Pleistocene glaciations. It is restricted to areas with occurrence of calcareous bedrock, especially limestones. It appears to be rather isolated genetically based on molecular studies of total ITS. It is sister to the large clade, ‘Apocarpum’, which consists of species which probably embody its closest known extant relatives.

Circaea × intermedia in eastern North America with particular reference to Ontario

1977 ◽  
Vol 55 (23) ◽  
pp. 2919-2935 ◽  
Author(s):  
Erich Haber
Keyword(s):  
North America ◽  
North American ◽  
Chromosome Numbers ◽  
Interspecific Hybrid ◽  
Somatic Chromosome ◽  
Parental Species ◽  
Eastern North America ◽  
Chromosome Counts ◽  
Morphological Differences ◽  
Somatic Chromosome Numbers

Circaea × intermedia Ehrh. in North America is an interspecific hybrid between C. alpina L. and C. lutetiana L. subsp. canadensis Aschers. & Magnus. In spite of the morphological differences that exist between the European and North American subspecies of C. lutetiana, hybrids from both continents are morphologically identical. Documentation of the intermediacy of the hybrid taxon is presented based on the evaluation of the means of 22 characters of specimens from an Ontario locality at which all three taxa are found.Diploid chromosome counts of 2n = 22 are reported for Ontario populations of the hybrid and parental species. The presence of irregular, somatic chromosome numbers are also reported for all three taxa.Distribution maps for all three taxa in eastern North America are included. In the case of C. lutetiana subsp. canadensis, the northern range is sharply delimited by the Precambrian–Paleozoic bedrock boundary.A table of character comparisons and a key to the three taxa summarizes the salient characteristics of the hybrid and the parental species in eastern North America.

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