An examination of some Hexarthra species (Rotatoria) from western Canada and Nepal

1978 ◽  
Vol 56 (3) ◽  
pp. 440-445 ◽  
Author(s):  
Henri J. Dumont ◽  
Marc Coussement ◽  
R. Stewart Anderson
Keyword(s):  
Rocky Mountains ◽  
Saline Lake ◽  
Rocky Mountain ◽  
Diagnostic Character ◽  
High Mountain ◽  
Western Canada ◽  
Lake Van ◽  
High Altitudes ◽  
New Subspecies ◽  
Low Salinity

Four species of Hexarthra are reported from ponds and lakes in western Canada. Two Rocky Mountain forms are described as new subspecies: Hexarthra bulgarica canadensis n.subsp., at high altitudes, and Hexarthra polyodonta jasperina n.subsp. The nominate subspecies of the latter is known only from saline Lake Van, Turkey. Hexarthra polyodonta jasperina occurs in low salinity lakes and differs morphologically from the nominate subspecies in having a moderately developed ventro-anterior lip. Hexarthra bulgarica bulgarica is a true high-mountain rotifer known from the Rila Mountains, Bulgaria (nominate subspecies), from the Himalayas (H. bulgarica nepalensis n.subsp.), and from the Rocky Mountains (H. bulgarica canadensis n.subsp.). The Nepalese subspecies differs from the nominate subspecies and from H. bulgarica canadensis in having a well developed ventro-anterior lip. Hexarthra bulgarica canadensis differs from the nominate subspecies in having more teeth on the unci, more spines on the ventral arm, and more filaments on all arms. The pair of spines on the dorsolateral arm is the main diagnostic character of the H. bulgarica group. Hexarthra mira (Hudson) occurred at intermediate and lower altitudes, and Hexarthra fennica (Levander) was identified from a saline lake in Saskatchewan where specimens were unusually large, but otherwise typical.

INSECTS OF WESTERN CANADA, WITH SPECIAL REFERENCE TO CERTAIN CARABIDAE (COLEOPTERA): PRESENT DISTRIBUTION PATTERNS AND THEIR ORIGINS

1980 ◽  
Vol 112 (11) ◽  
pp. 1129-1144 ◽  
Author(s):  
David H. Kavanaugh
Keyword(s):  
Rocky Mountains ◽  
Rocky Mountain ◽  
Distribution Patterns ◽  
Mountain Region ◽  
Western Canada ◽  
Cascade Mountains ◽  
Insect Fauna ◽  
History Of ◽  
Mountain Systems ◽  
Present Distribution

AbstractMunroe (1956) summarized knowledge of the distribution patterns and history of the Canadian insect fauna; and a general synthesis beyond his conclusions is not yet possible. Results of studies on Nearctic Nebria taxa illustrate present distribution patterns and provide clues to the history of the montane fauna of western Canada. Nebria species and subspecies diversity is greatest in the Coast/Cascade Mountains just south of Canada and decreases northward. Major centers of endemism are located south of Canada, in the Coast/Cascade and southern Rocky Mountain systems, with minor centers found in western Alberta and the Queen Charlotte Islands. Species and subspecies vicariance patterns link Coast/Cascade and Rocky Mountain systems across the Okanagan lowland; and subspecies vicariance patterns link (1) Coast and Cascade mountains across Puget lowland/Georgia Strait and (2) central Canadian Rocky Mountains and Rocky Mountains of western Wyoming. These and other data presented on Nebria distribution patterns and faunal similarities among different mountain ranges and systems suggest that the present montane fauna of western Canada is derived from two source areas—one in the Coast/Cascade Mountain region, one in the Rocky Mountain region, each just south of the Canadian/U.S. border—which were separate and distinct during and after Wisconsinan time. Northern (e.g. Beringian) Wisconsinan refugia apparently did not contribute significantly to the present montane fauna.

Mitbringsel aus den Ferien

Praxis ◽  
2005 ◽  
Vol 94 (47) ◽  
pp. 1869-1870
Author(s):  
Balestra ◽  
Nüesch
Keyword(s):  
Rocky Mountains ◽  
Spotted Fever ◽  
Rocky Mountain ◽  
Rickettsia Conorii ◽  
Rocky Mountain Spotted Fever ◽  
Klinische Diagnose ◽  
Rickettsia Rickettsii

Eine 37-jährige Patientin stellt sich nach der Rückkehr von einer Rundreise durch Nordamerika mit einem Status febrilis seit zehn Tagen und einem makulösem extremitätenbetontem Exanthem seit einem Tag vor. Bei suggestiver Klinik und Besuch der Rocky Mountains wird ein Rocky Mountain spotted fever diagnostiziert. Die Serologie für Rickettsia conorii, die mit Rickettsia rickettsii kreuzreagiert, war positiv und bestätigte die klinische Diagnose. Allerdings konnte der beweisende vierfache Titeranstieg, möglicherweise wegen spät abgenommener ersten Serologie, nicht nachgewiesen werden. Nach zweiwöchiger antibiotischer Therapie mit Doxycycline waren Status febrilis und Exanthem regredient.

Tectonic controls on basement exhumation in the southern Rocky Mountains (United States): The power of combined zircon (U-Th)/He and K-feldspar 40Ar/39Ar thermochronology

Geology ◽  
2021 ◽  
Author(s):  
Jason W. Ricketts ◽  
Jacoup Roiz ◽  
Karl E. Karlstrom ◽  
Matthew T. Heizler ◽  
William R. Guenthner ◽  
...  
Keyword(s):  
Rocky Mountains ◽  
Rocky Mountain ◽  
Snowball Earth ◽  
Southern Rocky Mountains ◽  
Basement Rocks ◽  
Rocky Mountain Region ◽  
Multi Stage ◽  
Inverse Models ◽  
Multiple Pulses ◽  
Differential Uplift

The Great Unconformity of the Rocky Mountain region (western North America), where Precambrian crystalline basement is nonconformably overlain by Phanerozoic strata, represents the removal of as much as 1.5 b.y. of rock record during 10-km-scale basement exhumation. We evaluate the timing of exhumation of basement rocks at five locations by combining geologic data with multiple thermochronometers. 40Ar/39Ar K-feldspar multi-diffusion domain (MDD) modeling indicates regional multi-stage basement cooling from 275 to 150 °C occurred at 1250–1100 Ma and/or 1000–700 Ma. Zircon (U-Th)/He (ZHe) dates from the Rocky Mountains range from 20 to 864 Ma, and independent forward modeling of ZHe data is also most consistent with multi-stage cooling. ZHe inverse models at five locations, combined with K-feldspar MDD and sample-specific geochronologic and/or thermochronologic constraints, document multiple pulses of basement cooling from 250 °C to surface temperatures with a major regional basement exhumation event 1300–900 Ma, limited cooling in some samples during the 770–570 Ma breakup of Rodinia and/or the 717–635 Ma snowball Earth, and ca. 300 Ma Ancestral Rocky Mountains cooling. These data argue for a tectonic control on basement exhumation leading up to formation of the Precambrian-Cambrian Great Unconformity and document the formation of composite erosional surfaces developed by faulting and differential uplift.

scholarly journals Autumn Raptor Migration in Yellowstone National Park, 2011–2015

2018 ◽  
Vol 131 (4) ◽  
pp. 303-311
Author(s):  
Lisa M. Baril ◽  
David B. Haines ◽  
Lauren E. Walker ◽  
Douglas W. Smith
Keyword(s):  
Rocky Mountains ◽  
Yellowstone National Park ◽  
National Park ◽  
Rocky Mountain ◽  
Cost Effective ◽  
Single Species ◽  
Future Research ◽  
Individual Species ◽  
Relative Role ◽  
Stopover Site

Raptors are wide-ranging, vagile avian predators whose populations can be difficult and costly to monitor on their breeding or winter range. However, monitoring raptors during their annual northbound or southbound migration is a cost-effective and efficient alternative to time-intensive, single-species breeding surveys. In 2010, we observed numerous Swainson’s Hawks (Buteo swainsoni) and Red-tailed Hawks (Buteo jamaicensis) migrating through the Hayden Valley in central Yellowstone National Park, prompting an investigation into raptor migration patterns in the park. Our objectives were to monitor annual autumn raptor migration in Hayden Valley from 2011 to 2015 and to determine the relative role of this undocumented migration site by comparing our observations to simultaneously collected migration data from three other sites in the Rocky Mountain Flyway. From 2011 to 2015, we observed 6441 raptors of 17 species across 170 d and 907 h of observation. Red-tailed Hawks, Swainson’s Hawks, and Golden Eagles (Aquila chrysaetos) accounted for 51% of the total individuals observed over five years. Overall counts from Hayden Valley were comparable to counts from the three migration sites in the Rocky Mountains, although abundance of individual species varied by site. Data from this study suggest that Hayden Valley may serve as a stopover site for migrating raptors and presents an opportunity for future research. By improving our understanding of where raptors migrate and the characteristics of stopover areas in the Rocky Mountains, land managers may develop effective strategies for protecting raptor populations and habitat from threats including development and climate change.

THE ROCKY MOUNTAIN TRENCH: A PROBLEM

1964 ◽  
Vol 1 (3) ◽  
pp. 184-205 ◽  
Author(s):  
C. H. Crickmay
Keyword(s):  
Rocky Mountains ◽  
Rocky Mountain ◽  
Canadian Rocky Mountains ◽  
The West ◽  
West Side ◽  
Combined Action ◽  
Headward Erosion

The Rocky Mountain Trench is defined as the 1 000-mile valley which marks the west side of the Canadian Rocky Mountains. The background of the Trench as a problem is examined, and descriptions, geographical and geological, are given. Previous work on Trench origin is reviewed and note is taken of the seeming inapplicability of accepted erosion theories to the making of the erosion-made Trench. An hypothesis is offered in which the combined action of drainage hemmed in by bordering uplifts, guided headward erosion, lateral corrasion, and streams repeatedly reversed by continuing diastrophism is suggested as the excavator of the Trench, a valley characterized by the puzzling peculiarity of continuous depth without a consistent gradient.

MEASUREMENT OF THE THICKNESS OF THE EARTH’S CRUST IN THE ALBERTAN PLAINS OF WESTERN CANADA

Geophysics ◽  
1959 ◽  
Vol 24 (2) ◽  
pp. 262-284 ◽  
Author(s):  
T. C. Richards ◽  
D. J. Walker
Keyword(s):  
Rocky Mountains ◽  
Intermediate Layer ◽  
Earth’S Crust ◽  
Western Canada ◽  
American Continent ◽  
Minimum Depth ◽  
Earth's Crust ◽  
Mohorovičić Discontinuity

Following seismic observations in the Albertan Plains from the Ripple Rock explosion, a refraction line some 81 miles long and parallel to the frontal thrust of the Rocky Mountains and about 60 miles to the east thereof was observed by two‐way shooting. Fifteen seismic parties, spaced at roughly uniform intervals along the line and using the method of close geophone correlation, were employed, the object being to map as many refractors or reflectors as possible as far as the Mohorovicic discontinuity. The results indicate that this discontinuity occurs at a minimum depth of 43 km where the velocity is about 8.2 km/sec, while an intermediate layer with a minimum depth of 29 km and velocity 7.2 km/sec has been registered. Other intermediate refractors were observed. These results are compared with those obtaining in other parts of the American continent and elsewhere. The operational, instrumental, and theoretical aspects of the work are discussed.

New synonyms and a new subspecies of Macrogomphus Selys, 1858 (Odonata: Gomphidae) from continental south-east Asia

Zootaxa ◽  
2019 ◽  
Vol 4615 (1) ◽  
pp. 57
Author(s):  
OLEG E. KOSTERIN
Keyword(s):  
East Asia ◽  
Great Lake ◽  
Diagnostic Character ◽  
South East Asia ◽  
New Subspecies ◽  
New Synonyms ◽  
Siem Reap ◽  
Tonle Sap ◽  
Lake Tonle Sap ◽  
The Relationship

The taxa of the genus Macrogomphus Selys, 1858 occurring in continental south-east Asia are reconsidered. Macrogomphus rivularis Förster, 1914 (described from Vietnam), M. borikhanensis Fraser, 1933 (described from Laos), and M. guilinensis Chao, 1983 (described from China), are synonymised with M. albardae Selys, 1878. The relationship and conspecificity of the latter with M. parallelogramma Burmeister, 1839 are doubtful, perhaps they are bona species. Males of M. albardae (and seemingly of parallelogramma as well) are approximately trimorphic for the pale pattern of the abdominal S3–S6, being of either a ‘dashed morph’ (with small isolated anteriolateral spots and conspicuous middorsal streaks), or a ‘ringed morph (with broad anterior rings and less conspicuous middorsal streaks), or an ‘intermediate morph’. Validity of the species M. matsukii Asahina, 1986 is doubted; its holotype could be an aberrant male of M. albardae. The main diagnostic character of M. albardae, M. phalantus Lieftinck, 1935 and probably M. parallelogramma, is clarified to be the structure of the cercus inner branch. M. phalantus jayavarman subsp. nov. is described from temporarily inundated forest at the northern bank of the great Lake Tonlé Sap of Cambodia (Siem Reap Province, 1.5 km SSW of Kampong Pluk village, 13.1956° N, 103.9725° E, 3 m a.s.l.), which is ca 1,300 km north and overseas from the presumed range of M. phalantus phalantus. 

scholarly journals Provenance of Pennsylvanian–Permian sedimentary rocks associated with the Ancestral Rocky Mountains orogeny in southwestern Laurentia: Implications for continental-scale Laurentian sediment transport systems

Lithosphere ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 88-121 ◽  
Author(s):  
Ryan J. Leary ◽  
Paul Umhoefer ◽  
M. Elliot Smith ◽  
Tyson M. Smith ◽  
Joel E. Saylor ◽  
...  
Keyword(s):  
Sediment Transport ◽  
Rocky Mountains ◽  
Detrital Zircon ◽  
Rocky Mountain ◽  
Sedimentary Basins ◽  
The Arctic ◽  
Transport Systems ◽  
Published Data ◽  
Transport Pathways ◽  
Continental Scale

Abstract The Ancestral Rocky Mountains system consists of a series of basement-cored uplifts and associated sedimentary basins that formed in southwestern Laurentia during Early Pennsylvanian–middle Permian time. This system was originally recognized by aprons of coarse, arkosic sandstone and conglomerate within the Paradox, Eagle, and Denver Basins, which surround the Front Range and Uncompahgre basement uplifts. However, substantial portions of Ancestral Rocky Mountain–adjacent basins are filled with carbonate or fine-grained quartzose material that is distinct from proximal arkosic rocks, and detrital zircon data from basins adjacent to the Ancestral Rocky Mountains have been interpreted to indicate that a substantial proportion of their clastic sediment was sourced from the Appalachian and/or Arctic orogenic belts and transported over long distances across Laurentia into Ancestral Rocky Mountain basins. In this study, we present new U-Pb detrital zircon data from 72 samples from strata within the Denver Basin, Eagle Basin, Paradox Basin, northern Arizona shelf, Pedregosa Basin, and Keeler–Lone Pine Basin spanning ∼50 m.y. and compare these to published data from 241 samples from across Laurentia. Traditional visual comparison and inverse modeling methods map sediment transport pathways within the Ancestral Rocky Mountains system and indicate that proximal basins were filled with detritus eroded from nearby basement uplifts, whereas distal portions of these basins were filled with a mix of local sediment and sediment derived from marginal Laurentian sources including the Arctic Ellesmerian orogen and possibly the northern Appalachian orogen. This sediment was transported to southwestern Laurentia via a ca. 2,000-km-long longshore and aeolian system analogous to the modern Namibian coast. Deformation of the Ancestral Rocky Mountains slowed in Permian time, reducing basinal accommodation and allowing marginal clastic sources to overwhelm the system.

Study of Long Combination Vehicles on Two-Lane Highways

1998 ◽  
Vol 1613 (1) ◽  
pp. 43-49 ◽  
Author(s):  
Raymond A. Barton ◽  
John Morrall
Keyword(s):  
High Speed ◽  
Rocky Mountain ◽  
Highway Safety ◽  
Level Of Service ◽  
Western Canada ◽  
Maximum Volume ◽  
Vehicle Type ◽  
Heavy Trucks ◽  
Traffic Volumes ◽  
Council Of Ministers

In 1988, the Council of Ministers of Transportation and Highway Safety in Canada endorsed a memorandum of understanding designed to improve uniformity between provinces and territories. The regulations covering weights and dimensions for tractor-semitrailers and double combination trucks specified a maximum length of 23 m. However, in western Canada, which includes the provinces of British Columbia, Alberta, Saskatchewan, and Manitoba, a maximum vehicle length of 25 m was adopted. Vehicles longer than 25 m are generally referred to as long combination vehicles (LCVs) and include the following vehicles: triple trailer combinations, 35 m in length; Rocky Mountain doubles, 30 m in length; log haul trucks, which can be up to 30.5 m in length; and turnpike doubles, 38 m in length. A study was conducted to develop recommendations relating to the use of LCVs on two-lane highways in Alberta. The basic approach was to examine the incremental impact of LCV-type vehicles on two-lane highway operations compared with a baseline vehicle type, namely, 25-m standard double heavy trucks. Although the study of LCVs examined a range of issues that included low- and high-speed offtracking, and aerodynamic buffeting, only the findings related to traffic volume criteria are presented. The main recommendation with respect to passing opportunities and level of service was the development of maximum traffic volumes for two-lane highways with and without passing lanes and with a given percentage of passing zones. The main criteria are to ensure that a net passing opportunity of at least 30 percent is provided to drivers impeded by LCVs. This is roughly comparable to providing to Level of Service C. For example, the maximum volume below which Rocky Mountain doubles may operate on a two-lane highway is 425 veh/h for a section with 100 percent passing zones. If 2-km passing lanes are provided every 10 km, Rocky Mountain doubles could operate at traffic volumes up to 734 veh/h and still ensure a net passing opportunity of 30 percent.

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