Isoetes ×pseudotruncata, a new triploid hybrid from western Canada and Alaska

1996 ◽  
Vol 74 (1) ◽  
pp. 51-59 ◽  
Author(s):  
Donald M. Britton ◽  
Daniel F. Brunton
Keyword(s):  
Electron Microscopy ◽  
British Columbia ◽  
Pacific Coast ◽  
Western Canada ◽  
Triploid Hybrid ◽  
Freshwater Habitat ◽  
Spore Ornamentation ◽  
The Pacific ◽  
Northwestern North America ◽  
Scanning Electron

A new interspecific Isoetes hybrid, I. echinospora Dur. ×I. maritima Underw., is described from Vancouver Island, British Columbia and southern Alaska by means of cytology and the scanning electron microscopy of spores. Isoetes ×pseudotruncata D.M. Britton and D.F. Brunton, hyb.nov. is the name proposed for this taxon. It is triploid and produces only aborted, sterile spores and has spore ornamentation features intermediate between those of its putative parents. Several concentrations of hybrids have been identified, each growing with both parents in shallow, freshwater habitat along the Pacific Coast of northwestern North America. Keywords: Isoetes echinospora, Isoetes maritima, hybrid, British Columbia.

Isoetes × marensis, a new interspecific hybrid from western Canada

1995 ◽  
Vol 73 (9) ◽  
pp. 1345-1353 ◽  
Author(s):  
Donald M. Britton ◽  
Daniel F. Brunton
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
British Columbia ◽  
Key Words ◽  
North American ◽  
Interspecific Hybrid ◽  
Western Canada ◽  
Hybrid Plants ◽  
Surface Ornamentation ◽  
Scanning Electron

A new interspecific hybrid in Isoetes, I. maritima Underw. × I. howellii Engelm., is delineated and described from the Shuswap Highlands region of British Columbia by means of cytology and scanning electron microscopy of spores. Isoetes × marensis D.M. Britton and D.F. Brunton, hyb.nov. is the name proposed for this taxon. It is triploid (3x; 2n = 33) and is believed to produce only sterile and (or) aborted spores. Hybrid plants have polymorphic spores that demonstrate size and surface ornamentation features intermediate between those of the putative parents. Three populations were examined, each growing with both of the putative parents in silt and sand among granite cobble over clay along an emergent lakeshore. Isoetes × marensis is the first described North American hybrid involving an amphibious Isoetes. It is expected to be a rare taxon owing to the restricted sympatric area of the putative parents and their tendency to occupy different habitats. Key words: Isoetes, Isoetes howellii, Isoetes maritima, hybrid, British Columbia.

scholarly journals A reexamination of Yuknessia from the Cambrian of British Columbia and Utah

2015 ◽  
Vol 89 (1) ◽  
pp. 82-95 ◽  
Author(s):  
Steven T. LoDuca ◽  
Jean-Bernard Caron ◽  
James D. Schiffbauer ◽  
Shuhai Xiao ◽  
Anthony Kramer
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
British Columbia ◽  
National Park ◽  
Red Alga ◽  
Fine Scale ◽  
Burgess Shale ◽  
Phylogenetic Affinity ◽  
New Material ◽  
Scanning Electron

AbstractTo investigate the phylogenetic affinity of Yuknessia simplex Walcott, 1919, scanning electron microscopy was applied to the Burgess Shale (Cambrian Series 3, Stage 5) type material and to new material from the Trilobite Beds (Yoho National Park) and specimens from the Cambrian of Utah. On the basis of fine-scale details observed using this approach, including banding structure interpreted as fusellae, Yuknessia Walcott, 1919 is transferred from the algae, where it resided for nearly a century, to the extant taxon Pterobranchia (Phylum Hemichordata). Considered as such, Yuknessia specimens from the Trilobite Beds and Spence Formation (Utah) are amongst the oldest known colonial pterobranchs. Two morphs regarded herein as two different species are recognized from the Trilobite Beds based on tubarium morphology. Yuknessia simplex has slender erect tubes whereas Yuknessia stephenensis n. sp., which is also known in Utah, has more robust erect tubes. The two paratypes of Y. simplex designated by Walcott (1919) are formally removed from Yuknessia and are reinterpreted respectively as an indeterminate alga and Dalyia racemata Walcott, 1919, a putative red alga.

Summary of Coastal Geologic Evidence for past Great Earthquakes at the Cascadia Subduction Zone

1995 ◽  
Vol 11 (1) ◽  
pp. 1-18 ◽  
Author(s):  
Brian F. Atwater ◽  
Alan R. Nelson ◽  
John J. Clague ◽  
Gary A. Carver ◽  
David K. Yamaguchi ◽  
...  
Keyword(s):  
British Columbia ◽  
North America ◽  
Subduction Zone ◽  
Forest Soils ◽  
Pacific Coast ◽  
Cascadia Subduction Zone ◽  
Level Change ◽  
The Past ◽  
The Pacific ◽  
Juan De Fuca

Earthquakes in the past few thousand years have left signs of land-level change, tsunamis, and shaking along the Pacific coast at the Cascadia subduction zone. Sudden lowering of land accounts for many of the buried marsh and forest soils at estuaries between southern British Columbia and northern California. Sand layers on some of these soils imply that tsunamis were triggered by some of the events that lowered the land. Liquefaction features show that inland shaking accompanied sudden coastal subsidence at the Washington-Oregon border about 300 years ago. The combined evidence for subsidence, tsunamis, and shaking shows that earthquakes of magnitude 8 or larger have occurred on the boundary between the overriding North America plate and the downgoing Juan de Fuca and Gorda plates. Intervals between the earthquakes are poorly known because of uncertainties about the number and ages of the earthquakes. Current estimates for individual intervals at specific coastal sites range from a few centuries to about one thousand years.

Gyrodiform gastropods from the Pacific Coast Cretaceous and Paleocene

1987 ◽  
Vol 61 (1) ◽  
pp. 70-100 ◽  
Author(s):  
W. P. Popenoe ◽  
L. R. Saul ◽  
Takeo Susuki
Keyword(s):  
British Columbia ◽  
New Taxa ◽  
Late Cretaceous ◽  
West Coast ◽  
Pacific Coast ◽  
Northern California ◽  
Color Patterns ◽  
New Subgenus ◽  
The Pacific

Seven previously described and seven new taxa of gyrodiform naticoids from West Coast Late Cretaceous–Paleocene age strata are discussed. Gyrodes (Gyrodes) dowelli White of Turonian age is a typical Gyrodes; G. robustus Waring from the Paleocene has the shape of Gyrodes s.s. but lacks the crenulations. G. greeni Murphy and Rodda, G. yolensis n. sp., G. quercus n. sp., G. banites n. sp., G. canadensis Whiteaves, G. pacificus n. sp., and G. expansus Gabb comprise the new subgenus Sohlella, which thus ranges from Cenomanian through Maastrichtian. Gyrodes robsauli n. sp. resembles “Polinices” (Hypterita) helicoides (Gray), and Hypterita is reassigned to the Gyrodinae as a subgenus of Gyrodes. Gyrodes onensis n. sp. of Albian age is similar to the G. americanus group of Sohl (1960). Three texa—Natica allisoni (Murphy and Rodda) of Cenomanian age and N. conradiana Gabb and N. conradiana vacculae n. subsp. of Turonian age—which have all been previously considered to be Gyrodes are placed in Natica. Well marked relict color patterns on N. conradiana and N. conradiana vacculae suggest that these naticids from northern California and southern British Columbia were tropical forms.Diversity of taxa and size of specimens are reduced at the end of the Turonian, suggesting a change in West Coast marine conditions at that time.

First Records of the Striped Bass, Morone saxatilis, in British Columbia Waters

1972 ◽  
Vol 29 (3) ◽  
pp. 337-339 ◽  
Author(s):  
C. R. Forrester ◽  
Alex E. Peden ◽  
R. M. Wilson
Keyword(s):  
British Columbia ◽  
Striped Bass ◽  
Pacific Coast ◽  
Puget Sound ◽  
Morone Saxatilis ◽  
San Juan ◽  
Barkley Sound ◽  
The Pacific

Two specimens of the striped bass (Morone saxatilis) were taken in British Columbia waters in 1971. One was taken off Port San Juan (48°30′N, 124°30′W) and one in Barkley Sound (48°58′N, 125°03′W). Previous most northerly published record for the Pacific coast was from Puget Sound, Washington.

Additions to the Polychaete Fauna of Canada, with Comments on Some Older Records

1954 ◽  
Vol 11 (4) ◽  
pp. 454-471 ◽  
Author(s):  
E. Berkeley ◽  
C. Berkeley
Keyword(s):  
New Species ◽  
North America ◽  
Pacific Coast ◽  
Western Canada ◽  
New Genera ◽  
Eastern Canada ◽  
New Variety ◽  
The Pacific

Descriptions are given of the new genera Neopygospio (type N. laminifera, nov.) and Novobranchus (type N. pacificus, nov.); of the new species Nereis (Eunereis) wailesi, Spio butleri, Neopygospio laminifera, Novobranchus pacificus; and of the new variety pacificus of Distylia volutacornis (Montagu). All are from the Pacific coast of Canada. Synonymy is proposed of Lepidonotus caelorus Moore with L. squamatus (Linné), and of Goniada eximia Ehlers with Ophioglycera gigantea Verrill. In addition to the new species and variety, records of three species new to western Canada are presented, and notes on others. Thirteen species and a variety new to eastern Canada are recorded, one of them new to North America.

The Life History and Habits of Scolytus unispinosus Leconte (Coleoptera: Scolytidae) in the Interior of British Columbia

1962 ◽  
Vol 94 (1) ◽  
pp. 17-25 ◽  
Author(s):  
L. H. McMullen ◽  
M. D. Atkins
Keyword(s):  
British Columbia ◽  
Bark Beetles ◽  
Pacific Coast ◽  
Rocky Mountain ◽  
Economic Importance ◽  
Douglas Fir ◽  
Dendroctonus Pseudotsugae ◽  
Rocky Mountain Region ◽  
The Pacific ◽  
Standing Timber

The Douglas-fir engraver, Scolytus unispinosus Leconte, is a common bark beetle throughout the Pacific Coast and Rocky Mountain Region of North America. Although it occasionally kills young trees (Chamberlin, 1939), it is of minor economic importance, usually confining its attack to tops, limbs and logging slash. In standing timber it acts primarily as a secondary insect, attacking the tops and branches of trees killed or severely weakened by other agents. In the interior of British Columbia it is commonly found in Douglas fir, Pseudotsuga menziesii (Mirb.) Franco, and thus it is of interest as an associate of the Douglas-fir beetle, Dendroctonus pseudotsugae Hopk. Two other bark beetles Pseudohylesinus nebulosus (Leconte) and Scolytus tsugae (Swaine) with similar associations were studied earlier (Walters and McMullen, 1956; McMullen and Atkins, 1959).

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