Geographic structure of sibling species and cytotypes of the Simulium arcticum complex (Diptera: Simuliidae) in rivers of central Idaho and southeastern Washington, United States of America

2018 ◽  
Vol 150 (3) ◽  
pp. 366-377 ◽  
Author(s):  
Gerald F. Shields ◽  
John P. Shields

AbstractWe made 37 collections and analysed the polytene chromosomes of salivary glands of 726 larvae of the Simulium arcticum Malloch (Diptera: Simuliidae) complex from 10 locations in an unstudied region from central Idaho and southeastern Washington, United States of America. We compared our results to previous population cytotaxonomic research on larvae of this complex from western Montana, northern Idaho, and eastern Washington, United States of America. We identified four sibling species, S. brevicercum Knowlton and Rowe, S. saxosum Adler, S. arcticum sensu stricto, S. apricarium Adler, Currie, and Wood; and three cytotypes, S. arcticum IIL-9, IIL-17, and IIL-79, previously described by us. We discovered a new cytotype, S. arcticum IIL-80, at three locations in the western region of our sample area. We also found combinational (ancestral) types between S. saxosum and S. arcticum sensu stricto and between S. saxosum and S. arcticum IIL-79, suggesting that ancestral populations of the complex still exist. Geographic structuring of these sibling species and cytotypes are documented given that S. saxosum occurred in western regions, S. arcticum IIL-79 in northeastern regions, and S. apricarium in southeastern regions of our study area.

2000 ◽  
Vol 78 (11) ◽  
pp. 1469-1481 ◽  
Author(s):  
Stephen J Novak ◽  
Richard N Mack

Bryonia alba L. (Cucurbitaceae) is a herbaceous Eurasian vine that predominantly reproduces clonally (asexually) through apomixis. We assessed the magnitude and distribution of clonal diversity within and among 23 recently established populations of B. alba in its new range in the western United States, based on the distribution of multilocus isozyme genotypes. Fifty-two unique clones were detected: 30 in the nine populations from eastern Washington and northern Idaho, and the remaining 22 in 14 populations from western Montana, northern Utah, and southern Idaho. On average, each population of B. alba was composed of 6.4 clones, and the proportion of distinguishable clones was 0.275. Multilocus diversity (D) was 0.632 and multilocus evenness (E) was 0.556. Twenty-six of 52 clones (50%) were restricted to a single population, and, on average, each clone occurred in 2.83 populations. Compared with other clonally reproducing plant species, this vine possesses moderate to high levels of clonal diversity in its new range in the western United States. This diversity appears to be a consequence of the events associated with its introduction (including multiple introductions), founder effects, and the proportion of sexual to apomictic reproduction within populations.Key words: invasive vine, apomixis, multilocus genotypes, clonal diversity and evenness, Bryonia alba, Cucurbitaceae.


1978 ◽  
Vol 15 (10) ◽  
pp. 1554-1567 ◽  
Author(s):  
J. A. Westgate ◽  
M. E. Evans

Glacier Peak Volcano erupted many times during the period from ~11 000 to ~13 000 years ago and produced at least Three widespread tephra layers that serve as valuable stratigraphic markers in northwestern United States and the adjacent plains of southwestern Canada. Each of these units can be recognized by their stratigraphic, petrographic, and chemical attributes.Tephra was shed over eastern Washington, northern Idaho, western Montana, and southernmost Alberta during each of the eruptions responsible for the older two units; the other layer was deposited during the youngest and most violent event that directed tephra to the southeast as far as Yellowstone National Park, ~950 km from the volcano.Chemical data on glass, hornblende, hypersthene, feldspar, magnetite, and ilmenite show a systematic and unidirectional trend in tephra composition with age; earlier eruptions produced slightly more acidic tephra. This age–composition relationship is confirmed by palaeomagnetic data obtained from 116 specimens collected from two 5 m thick sections. It should therefore be possible to determine the relative age of Glacier Peak tephra samples by their composition alone.The chronology of the Glacier Peak eruptive sequence is still poorly understood. This is especially true of the oldest unit which has so far only been found in southeastern Alberta. Proximal occurrences should be sought in the bogs of eastern Washington where prospects of preservation and age definition are optimised.


2014 ◽  
Vol 146 (4) ◽  
pp. 415-428 ◽  
Author(s):  
Eugene R. Miliczky ◽  
David R. Horton ◽  
Eric LaGasa

AbstractThe eastern foothills of the Cascade Range in Washington State, United States of America are west of the State's major fruit-producing region. Alders (Alnus Hill (Betulaceae)), an important floristic component of riparian communities in the Cascade Range foothills, were surveyed for leafrolling caterpillars (Lepidoptera: Tortricidae) that might serve as alternate hosts for parasitoids of orchard pest leafrollers, particularly the nonnative wasp Colpoclypeus florus (Walker) (Hymenoptera: Eulophidae). Tortricid leafrollers were abundant on alder, but reared parasitoids did not include C. florus. Survey results also revealed that rolled leaves were secondarily colonised by a wide variety of predatory and phytophagous arthropods. Rolled leaves were almost 10-fold more likely to be occupied by predatory arthropods than adjacent, roll-free leaves. Phytophagous thrips and mites showed a similar preference for rolled leaves. The most abundant predaceous arthropods in the leafrolls were Anthocoris antevolens White (Hemiptera: Anthocoridae), found in 4.4% of leafrolls, and the spider Clubiona pacifica Banks (Araneae: Clubionidae), found in 8.3% of leafrolls. Both species, and several other predatory insect and spider species found in the rolled leaves, also occur in eastern Washington orchards where they contribute to biological control. Because of its frequent colonisation by beneficial arthropods, alder may prove useful in conservation biological control programs.


1996 ◽  
Vol 1 (1) ◽  
pp. 3-24 ◽  
Author(s):  
Alan Rodger

This article is the revised text of the first W A Wilson Memorial Lecture, given in the Playfair Library, Old College, in the University of Edinburgh, on 17 May 1995. It considers various visions of Scots law as a whole, arguing that it is now a system based as much upon case law and precedent as upon principle, and that its departure from the Civilian tradition in the nineteenth century was part of a general European trend. An additional factor shaping the attitudes of Scots lawyers from the later nineteenth century on was a tendency to see themselves as part of a larger Englishspeaking family of lawyers within the British Empire and the United States of America.


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