REVIEW OF THE MYRMECOPHILOUS PTOMAPHAGUS, SUBGENUS ECHINOCOLEUS (NEW STATUS), OF NORTH AMERICA (COLEOPTERA: LEIODIDAE: CHOLEVINAE: PTOMAPHAGINI)

1997 ◽  
Vol 129 (1) ◽  
pp. 93-104 ◽  
Author(s):  
Stewart B. Peck ◽  
Pedro Gnaspini
Keyword(s):  
United States ◽  
Phylogenetic Analysis ◽  
North America ◽  
Body Length ◽  
Southeastern United States ◽  
Western United States ◽  
Harvester Ants

AbstractWe here give Echinocoleus new ranking as a subgenus of Ptomaphagus. Ptomaphagus (Echinocoleus) acutus sp.nov. is described from the southeastern United States (Alabama, Georgia, Florida). It is the most plesiotypic member of a group in which all other species live in the western United States and (probably) adjacent Mexico. All are myrmecophilous with Pogonomyrmex and Aphaenogaster (= Novomessor) harvester ants. A phylogenetic analysis is given for the subgenus. The main synapomorphies of Echinocoleus, which are mostly interrelated with myrmecophily, are reduction of body length and broadening of elytra, reduction of antennal length, verticalization of mesocoxal insertion, reduction of mesosternal carina, body with a golden pubescense, and a pointed projection at the end of the spermatheca.

Neritoptyx hogansoninew species (Gastropoda, Mollusca) from the Upper Cretaceous Fox Hills Formation on the Dakota Isthmus, western United States

2018 ◽  
Vol 93 (2) ◽  
pp. 278-290
Author(s):  
J. Mark Erickson
Keyword(s):  
Heat Transfer ◽  
United States ◽  
New Species ◽  
North America ◽  
Upper Cretaceous ◽  
Gulf Coast ◽  
Western United States ◽  
Western Interior Seaway ◽  
Decapod Crustaceans ◽  
Upper Maastrichtian

AbstractIn midcontinent North America, the Fox Hills Formation (Upper Cretaceous, upper Maastrichtian) preserves the last marine faunas in the central Western Interior Seaway (WIS).Neritoptyx hogansoninew species, a small littoral snail, exhibited allometric change from smooth to corded ornament and rounded to shouldered shape during growth. Specimens preserve a zig-zag pigment pattern that changes to an axial pattern during growth.Neritoptyx hogansoninew species was preyed on by decapod crustaceans, and spent shells were occupied by pagurid crabs. Dead mollusk shells, particularly those ofCrassostrea subtrigonalis(Evans and Shumard, 1857), provided a hard substrate to which they adhered on the Fox Hills tidal flats. This new neritimorph gastropod establishes a paleogeographic and chronostratigraphic proxy for intertidal conditions on the Dakota Isthmus during the late Maastrichtian. Presence of a neritid extends the marine tropical/temperate boundary in the WIS northward to ~44° late Maastrichtian paleolatitude. Late Maastrichtian closure of the isthmus subsequently altered marine heat transfer by interrupting northward flow of tropical currents from the Gulf Coast by as much as 1 to 1.5 million years before the Cretaceous ended.UUID:http://zoobank.org/3ba56c07-fcca-4925-a2f0-df663fc3a06b

scholarly journals Progression of Sugarberry (Celtis laevigata) Dieback and Mortality in the Southeastern United States

2021 ◽  
Author(s):  
Emilee M Poole ◽  
Michael D Ulyshen ◽  
Scott Horn ◽  
Patrick Anderson ◽  
Chip Bates ◽  
...  
Keyword(s):  
United States ◽  
North America ◽  
Invasive Plants ◽  
Southeastern United States ◽  
Public Spaces ◽  
Canopy Gaps ◽  
Leaf Fall ◽  
Affected Area ◽  
Celtis Laevigata ◽  
Branch Dieback

Abstract The southeastern United States has been experiencing unexplained sugarberry (Celtis laevigata) mortality for over a decade, representing one of the most severe and widespread Celtis mortality episodes ever reported from North America. Here we describe external symptoms, progression of mortality, and the known geographic extent of the problem. More than half of all trees monitored at one site within the affected area died over five years of observation. Although many trees died within a year of first exhibiting symptoms (e.g., small yellow leaves, branch dieback, premature leaf fall), many others continued living for years after becoming symptomatic. A preliminary insecticide trial found no improvements in survivorship among trees treated with insecticides, emamectin benzoate and imidacloprid, relative to control trees. Our findings suggest the problem will likely continue and become more widespread in the coming years. Study Implications Sugarberry mortality in urban and forested environments is an ongoing problem that has the potential to spread throughout the southeastern United States and perhaps more widely, depending on the susceptibility of other native Celtis species. Many trees die within a year of first showing external symptoms, whereas others can live for many years after appearing symptomatic. Declining trees in rights-of-way and public spaces are presenting costly hazards to cities, and canopy gaps in natural areas are likely to facilitate the establishment and spread of invasive plants. Studies aimed at determining the cause of this problem are urgently needed.

Do centers of origin have a center?

Paleobiology ◽  
1981 ◽  
Vol 7 (3) ◽  
pp. 305-307 ◽  
Author(s):  
John C. Briggs
Keyword(s):  
United States ◽  
North America ◽  
Southeastern United States ◽  
Important Criterion ◽  
Centers Of Origin ◽  
Single Region ◽  
Evolutionary Radiation ◽  
A Current ◽  
Considerable Intensity

A current question being debated with considerable intensity is whether or not certain geographic areas act as centers of evolutionary radiation and supply species to other areas that are less active or less effective in an evolutionary sense. Darwin (1859) was the first to write about centers of origin which he called “single centers of creation.” He argued that each species was first produced within a single region and that it subsequently migrated from that area as far as its powers of migration and subsistence under past and present conditions permitted. Adams (1902), in discussing the influence of the southeastern United States as a center of distribution for the flora and fauna of North America, provided a series of criteria for the determination of “centers of dispersal.” His first, and evidently most important criterion was the location of “the greatest differentiation of a type.”

scholarly journals The Interannual Variability of the Haines Index over North America

2013 ◽  
Vol 52 (11) ◽  
pp. 2396-2409 ◽  
Author(s):  
Lejiang Yu ◽  
Shiyuan Zhong ◽  
Xindi Bian ◽  
Warren E. Heilman ◽  
Joseph J. Charney
Keyword(s):  
United States ◽  
Pacific Ocean ◽  
North America ◽  
Interannual Variability ◽  
Large Scale ◽  
Southern Oscillation ◽  
Southeastern United States ◽  
Lower Atmosphere ◽  
The Arctic ◽  
Fire Weather Index

AbstractThe Haines index (HI) is a fire-weather index that is widely used as an indicator of the potential for dry, low-static-stability air in the lower atmosphere to contribute to erratic fire behavior or large fire growth. This study examines the interannual variability of HI over North America and its relationship to indicators of large-scale circulation anomalies. The results show that the first three HI empirical orthogonal function modes are related respectively to El Niño–Southern Oscillation (ENSO), the Arctic Oscillation (AO), and the interdecadal sea surface temperature variation over the tropical Pacific Ocean. During the negative ENSO phase, an anomalous ridge (trough) is evident over the western (eastern) United States, with warm/dry weather and more days with high HI values in the western and southeastern United States. During the negative phase of the AO, an anomalous trough is found over the western United States, with wet/cool weather and fewer days with high HI, while an anomalous ridge occurs over the southern United States–northern Mexico, with an increase in the number of days with high HI. After the early 1990s, the subtropical high over the eastern Pacific Ocean and the Bermuda high were strengthened by a wave train that was excited over the tropical western Pacific Ocean and resulted in warm/dry conditions over the southwestern United States and western Mexico and wet weather in the southeastern United States. The above conditions are reversed during the positive phase of ENSO and AO and before the early 1990s.

scholarly journals The Sarracenia Pitcher Plants and Bog Gardening

2008 ◽  
pp. 79-99
Author(s):  
T Lawrence Mellichamp
Keyword(s):  
United States ◽  
North America ◽  
Extra Dimension ◽  
Southeastern United States ◽  
Short Note ◽  
Botanical Garden ◽  
Carnivorous Plants ◽  
Pitcher Plants ◽  
The Public ◽  
The World

The Sarracenia pitcher plants are among the world’s most beautiful and intriguing plants, and being carnivorous adds an extra dimension of fascination. They are endemic to North America – 10 species are found only in the southeastern United States and one species is widely distributed, from the northeastern US and across Canada. They are easy to cultivate if you understand their basic needs and are grown the world over. Every botanical garden should have them because they are so popular with the public. They go hand-in-hand with other unusual carnivorous plants to make a display that is captivating (puns intended!) to both children and adults. This paper covers types of pitcher plants, their habitats, brief descriptions of the species, a key to identification, cultivation and a short note on conservation.

Short-period P-wave attenuation along various paths in North America as determined from P-wave spectra of the SALMON nuclear explosion

1976 ◽  
Vol 66 (5) ◽  
pp. 1609-1622 ◽  
Author(s):  
Zoltan A. Der ◽  
Thomas W. McElfresh
Keyword(s):  
United States ◽  
North America ◽  
Wave Attenuation ◽  
Nuclear Explosion ◽  
P Wave ◽  
Western United States ◽  
Source Spectrum ◽  
Wave Spectra ◽  
Short Period ◽  
Q Values

abstract Average Q values were determined for ray paths to various LRSM stations from the SALMON nuclear explosion by taking ratios of observed P-wave spectra to the estimated source spectrum. Most Q values for P-wave paths throughout eastern North America are in the range 1600 to 2000 while those crossing over into the western United States are typically around 400 to 500. These differences in Q for intermediate distances can sufficiently explain the differences in the teleseismic event magnitudes observed, 0.3 to 0.4 magnitude units, in the western versus the eastern United States, if one assumes that the low Q layer under the western United States is located at depths less than 200 km.

A comparison of earthquake damage areas as a function of magnitude across the United States

1993 ◽  
Vol 83 (4) ◽  
pp. 1064-1080 ◽  
Author(s):  
G. A. Bollinger ◽  
M. C. Chapman ◽  
M. S. Sibol
Keyword(s):  
United States ◽  
North America ◽  
Ground Motion ◽  
Epicentral Distance ◽  
The United States ◽  
Western United States ◽  
Eastern North America ◽  
Similar Response ◽  
Eastern United States ◽  
The West

Abstract This study investigates the relationship between earthquake magnitude and the size of damage areas in the eastern and western United States. To quantify damage area as a function of moment magnitude (M), 149 MMI VI and VII areas for 109 earthquakes (88 in the western United States, 21 in the eastern United States and Canada) were measured. Regression of isoseismal areas versus M indicated that areas in the East were larger than those in the West, at both intensity levels, by an average 5 × in the M 4.5 to 7.5 range. In terms of radii for circles of equivalent area, these results indicate that damaging ground motion from shocks of the same magnitude extend 2 × the epicentral distance in eastern North America compared to the West. To determine source and site parameters consistent with the above results, response spectral levels for eastern North America were stochastically simulated and compared with response spectral ordinates derived from recorded strong ground motion data in the western United States. Stress-drop values of 200 bars, combined with a surficial 2-km-thick low velocity “sedimentary” layer over rock basement, produced results that are compatible with the intensity observations, i.e., similar response spectral levels in the east at approximately twice their epicentral distance in the western U.S. distance. These results suggest that ground motion modeling in eastern North America may need to incorporate source and site parameters different from those presently in general use. The results are also of importance to eastern U.S. hazard assessments as they require allowance for the larger damage areas in preparedness and mitigation programs.

The Biology of Downy Brome (Bromus tectorum)

Weed Science ◽  
1984 ◽  
Vol 32 (S1) ◽  
pp. 7-12 ◽  
Author(s):  
Donald C. Thill ◽  
K. George Beck ◽  
Robert H. Callihan
Keyword(s):  
United States ◽  
British Columbia ◽  
Triticum Aestivum ◽  
Bromus Tectorum ◽  
Southeastern United States ◽  
The United States ◽  
Early Spring ◽  
Western United States ◽  
Downy Brome ◽  
Perennial Grassland

Downy brome (Bromus tectorumL. # BROTE), also known as cheatgrass, downy chess, broncograss, Mormon oats, and junegrass, was introduced into the United States from Europe, apparently during the middle of the nineteenth century (11, 21). According to Mack (23), downy brome entered British Columbia, Washington, and Utah around 1890; and by 1928 it had reached its present range, occupying much of the perennial grassland in Washington, Idaho, Oregon, Nevada, Utah, and British Columbia. Today, downy brome is a widespread weed throughout most of Canada, Mexico, and the United States, except for the southeastern United States (5, 17). Some consider downy brome to be an important forage because it provides most of the early spring grazing for livestock in western United States rangeland (21). However, it is also considered a troublesome weed in rangeland (31), winter wheat (Triticum aestivumL.) (27), several other crops (29), and noncropland (32).

scholarly journals Molt Strategies and Age Differences in Migration Timing Among Autumn Landbird Migrants in Southwestern Idaho

The Auk ◽  
2005 ◽  
Vol 122 (4) ◽  
pp. 1070-1085 ◽  
Author(s):  
Jay D. Carlisle ◽  
Gregory S. Kaltenecker ◽  
David L. Swanson
Keyword(s):  
United States ◽  
North America ◽  
Age Differences ◽  
Western United States ◽  
Autumn Migration ◽  
Individual Species ◽  
Age Classes ◽  
Migration Timing ◽  
Breeding Grounds ◽  
Age And Sex

Abstract Intraspecific patterns of autumn migration timing are not well known, particularly in the western United States. Here, we (1) describe autumn migration timing and age ratios of landbird migrants in southwestern Idaho, (2) examine differences in timing among age and sex classes, and (3) demonstrate how prebasic molt strategies affect migration timing differences between age classes. As a group, Neotropical migrants were most common from late July through early September, whereas temperate migrants were most common from mid-September into early October. Proportion of hatch-year birds was 74.5% for all migrants combined and ranged from 33.3% to 100% for individual species. Timing differences between sex classes were detected in only a few species and no general patterns emerged. In 22 of 31 Neotropical and temperate migrants examined, there were significant differences in timing between adults and hatch-year birds. In species in which adults begin fall migration before replacing flight feathers, adults migrated earlier than hatch-year birds. Conversely, in species in which adults molt flight feathers on or near the breeding grounds before departing on fall migration, hatch-year birds migrated earlier than adults in all but one case. Therefore, it appears that molt strategy is a powerful determinant of intraspecific migration timing differences and, to our knowledge, this is the first study to document this pattern among migrant passerines of North America. Estrategias de Muda y Diferencias en el Momento de Migración Otoñal en Migrantes Terrestres en el Suroeste de Idaho

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