Taxonomic Characters of the Eastern North America Chars (Salvelinus and Cristivomer)

1954 ◽  
Vol 11 (6) ◽  
pp. 904-932 ◽  
Author(s):  
Vadim D. Vladykov
Keyword(s):  
North America ◽  
The Other ◽  
Eastern North America ◽  
Body Proportions ◽  
Meristic Characters ◽  
Pyloric Caeca ◽  
Other Hand ◽  
Taxonomic Relation ◽  
Distinct Genus ◽  
Fin Rays

For the present study about 300 specimens have been examined. These specimens belong to the six species of chars: C. namaycush, S. fontinalis, S. aureolus, S. oquassa, S. marstoni, and S. alpinus. Among meristic characters, the number of pyloric caeca was found to be very important. Body proportions and meristic characters, such as fin rays and vertebrae, are inadequate to properly describe a species. On the other hand, the skull bones, different teeth, and skeleton of the tail are sufficient in themselves to define a species. The pearl organs were found only in C. namaycush of both sexes. The taxonomic relation between species is as follows: C. namaycush belongs to a distinct genus; S. fontinalis represents a subgenus Baione; while the remaining chars are grouped in a subgenus Salvelinus.

On the mN, M Relation for Eastern North American Earthquakes

1987 ◽  
Vol 58 (4) ◽  
pp. 119-124 ◽  
Author(s):  
Gail M. Atkinson ◽  
David M. Boore
Keyword(s):  
North America ◽  
Stochastic Model ◽  
Ground Motion ◽  
Seismic Moment ◽  
The Other ◽  
Moment Magnitude ◽  
Scaling Relations ◽  
Eastern North America ◽  
Data Set ◽  
Meaningful Data

Abstract A stochastic model of ground motion has been used as a basis for comparison of data and theoretically-predicted relations between mN (commonly denoted by mbLg) and moment magnitude for eastern North America (ENA) earthquakes. mN magnitudes are recomputed for several historical ENA earthquakes, to ensure consistency of definition and provide a meaningful data set. We show that by itself the magnitude relation cannot be used as a discriminant between two specific spectral scaling relations, one with constant stress and the other with stress increasing with seismic moment, that have been proposed for ENA earthquakes.

scholarly journals Contribution to identify the causal gents of Dutch elm disease in the Czech Republic

2008 ◽  
Vol 43 (No. 4) ◽  
pp. 142-145 ◽  
Author(s):  
M. Dvořák ◽  
M. Tomšovský ◽  
L. Jankovský ◽  
D. Novotný
Keyword(s):  
Czech Republic ◽  
North America ◽  
Molecular Biology ◽  
The Other ◽  
Dutch Elm Disease ◽  
The Czech Republic ◽  
Ophiostoma Ulmi ◽  
Other Hand ◽  
Subspecies Level ◽  
First Time

This study provides new data on Dutch elm disease in the Czech Republic. <I>Ophiostoma novo-ulmi</I> is reported for the first time in the area of the Czech Republic, as well as both subspecies ssp. <I>novo-ulmi</I> (indigenous in the area of the Ukraine and Moldavia), and ssp. <I>Americana</I> indigenous in North America. The majority of the recorded strains belonged to <I>O. n.-u.</I> ssp. <I>novo-ulmi</I>, while <I>O. n.-u.</I> ssp. <I>Americana</I> and hybrids of these two subspecies were found less frequently. On the other hand, <I>Ophiostoma ulmi</I> was not found at all in the investigated samples. Identification on the subspecies level was performed by methods of molecular biology, i.e. PCR and RFLP of gene regions<I> cu</I> and <I>col1</I>.

North American Devonian Carydiidae (Bivalvia): systematics, phylogeny, and implications in early diversification of the class

1986 ◽  
Vol 60 (2) ◽  
pp. 302-326 ◽  
Author(s):  
J. Bowman Bailey
Keyword(s):  
North America ◽  
Diagnostic Criteria ◽  
North American ◽  
The Other ◽  
Eastern North America ◽  
Higher Taxa ◽  
Early Diversification ◽  
European Family

Although past authors have regarded the Carydiidae as a European family, six species of Carydium are reported here from the Devonian of eastern North America. Two of these belong to a single morphocline common in the Hamilton shales; another (Carydium clarkei) is new. Due to lack of well preserved hinges most of these species were earlier placed in Nucula because serrations or striations on dental elements were mistaken for a taxodont dentition.New data require modification of carydiid phylogenies of earlier authors. 1) Two independent pre-Devonian derivations from Lyrodesma are inferred. 2) Noradonta shergoldi, a carydiid-like lyrodesmatid from the Ordovician of Australia, is recognized as an important phyletic link between the Carydiidae and the Lyrodesmatidae. 3) The previous view of three distinct lineages within Carydium is not supported. Anamorphic data suggest as few as two main lineages and show two of the hinge types to be homeomorphic grades appearing separately or within one or the other of the main lineages.Though too young to be directly involved in the early diversification of the Bivalvia, the actinodont, subheterodont, and pseudotaxodont hinge morphologies of Carydium supply models for the origin of heterodont and taxodont hinges. Anamorphic and other evidence suggests that both are iterative types, and fundamental differences between them may be few. Hence, their preeminence as diagnostic criteria among higher taxa is diminished.

Reduced Mobility or the Bow and Arrow? Another Look at “Expedient” Technologies and Sedentism

2010 ◽  
Vol 75 (2) ◽  
pp. 259-286 ◽  
Author(s):  
Jim A. Railey
Keyword(s):  
New Mexico ◽  
North America ◽  
Agricultural Intensification ◽  
Causal Link ◽  
The Other ◽  
Other Hand ◽  
Bow And Arrow ◽  
Reduced Mobility ◽  
Subsistence Practices

Parry and Kelly (1987) argued for a causal link between expedient technologies and sedentism, and their explanation has widely influenced lithic analysts. There are some problems with their explanation, however, including disconnects in the reported timing of the shifts to expedient technologies, agricultural intensification, and sedentism. On the other hand, across much of North America the transition to an expedient technology appears to correlate more closely to the arrival of the bow and arrow. This is supported by data from a large excavation project in southern New Mexico, which shows that indicators of the shift to an expedient technology cannot be attributed to reduced mobility or any observable changes in subsistence practices, but do appear to correlate temporally with the appearance of arrow points.

The sawflies of the Pontania crassispina-group with a key for the genera of the subtribe Euurina (Hymenoptera: Tenthredinidae, Nematinae)

1999 ◽  
Vol 30 (3) ◽  
pp. 281-298 ◽  
Author(s):  
Veli Vikberg ◽  
Alexey G. Zinovjev
Keyword(s):  
New Species ◽  
North America ◽  
Eastern North America ◽  
Distinct Genus ◽  
Group A ◽  
Species Groups ◽  
A New Species

AbstractEupontania Zinovjev, 1985, originally described as a subgenus of Pontania, is treated as a distinct genus of the subtribe Euurina Vikberg, which consists of the genera Euura Newman, Eupontania Zinovjev (stat. n.), Pontania A. Costa and Phyllocolpa Benson. Separate keys are given to distinguish these genera and the species-groups of Pontania and Phyllocolpa, and for 11 species of the Pontania crassispinu-group. A new species, Pontania rotundidentata sp. n. is described from eastern North America. The lectotypes are designated for P. crassispina (Thomson) and P. joergenseni Enslin. Pontania devincta MacGillivray (syn. n.) is treated as a synonym of P. populi Marlatt.

NOTES ON SOME FLORIDA COLEOPTERA WITH DESCRIPTIONS OF NEW SPECIES

1928 ◽  
Vol 60 (3) ◽  
pp. 60-73 ◽  
Author(s):  
W. S. Blatchley
Keyword(s):  
New Species ◽  
North America ◽  
West Coast ◽  
The Other ◽  
Eastern North America ◽  
The West ◽  
Southern Florida

My last general paper on Florida Coleoptera was prepared in the autumn of 1924, and appeared in the Canadian Entomologist for July, 1925. Since that was written my time has been largely devoted to the final preparation and publication of the “Heteroptera of Eastern North America.” During the three years which have elapsed I have spent the winters at Dunedin on the west coast of Florida, but have made three additional collecting trips, of three or four weeks each, to Royal Palm Park. One of these was in December, the other two in March and April. This park comprises an area of 4,000 acres lying in extreme southern Florida, about 40 miles northeast of Cape Sable.

scholarly journals New records of theropods from the latest Cretaceous of New Jersey and the Maastrichtian Appalachian fauna

2019 ◽  
Vol 6 (11) ◽  
pp. 191206 ◽  
Author(s):  
Chase Doran Brownstein
Keyword(s):  
New Jersey ◽  
North America ◽  
Fossil Record ◽  
New Records ◽  
The Other ◽  
Eastern North America ◽  
Western North America ◽  
Northeastern North America ◽  
Terrestrial Vertebrate ◽  
Postcranial Remains

The faunal changes that occurred in the few million years before the Cretaceous–Palaeogene extinction are of much interest to vertebrate palaeontologists. Western North America preserves arguably the best fossil record from this time, whereas terrestrial vertebrate fossils from the eastern portion of the continent are usually limited to isolated, eroded postcranial remains. Examination of fragmentary specimens from the American east, which was isolated for the majority of the Cretaceous as the landmass Appalachia, is nonetheless important for better understanding dinosaur diversity at the end of the Mesozoic. Here, I report on two theropod teeth from the Mount Laurel Formation, a lower-middle Maastrichtian unit from northeastern North America. One of these preserves in detail the structure of the outer enamel and resembles the dentition of the tyrannosauroid Dryptosaurus aquilunguis among latest Cretaceous forms in being heavily mediolaterally compressed and showing many moderately developed enamel crenulations. Along with previously reported tyrannosauroid material from the Mt Laurel and overlying Cretaceous units, this fossil supports the presence of non-tyrannosaurid tyrannosauroids in the Campanian–Maastrichtian of eastern North America and provides evidence for the hypothesis that the area was still home to relictual vertebrates through the end of the Mesozoic. The other tooth is assignable to a dromaeosaurid and represents both the youngest occurrence of a non-avian maniraptoran in eastern North America and the first from the Maastrichtian reported east of the Mississippi. This tooth, which belonged to a 3–4 m dromaeosaurid based on size comparisons with the teeth of taxa for which skeletons are known, increases the diversity of the Maastrichtian dinosaur fauna of Appalachia. Along with previously reported dromaeosaurid teeth, the Mt Laurel specimen supports the presence of mid-sized to large dromaeosaurids in eastern North America throughout the Cretaceous.

Impatiens parviflora (small balsam).

2021 ◽  
Author(s):  
Rob Tanner
Keyword(s):  
North America ◽  
Environmental Impacts ◽  
Central Europe ◽  
Forest Vegetation ◽  
The Other ◽  
European Countries ◽  
Other Hand ◽  
Impatiens Parviflora ◽  
Undisturbed Forest ◽  
Successful Invader

Abstract I. parviflora is an exceptionally successful invader of many European countries. Its spread has been rapid, it is abundant in many parts of its exotic range and is one of few plants to successfully invade undisturbed forest vegetation. It is consequently regarded as undesirable by some, though there is little evidence of negative economic, social or environmental impacts. Further spread in central Europe is not likely as the species is already very abundant. In North America, on the other hand, it is still very localized. Even without clear evidence for impacts, a further spread there should not be encouraged by deliberate or careless transport of the species.

Inter-relationships of the Parasites of the Frit-fly, Oscinella frit (L.), in eastern North America

1953 ◽  
Vol 44 (2) ◽  
pp. 387-393 ◽  
Author(s):  
F. J. Simmonds
Keyword(s):  
Drosophila Melanogaster ◽  
North America ◽  
The Other ◽  
Eastern North America ◽  
Parasite Complex ◽  
Larval Parasites

Studies are reported on the extent and importance of competition amongst larval and pupal parasites of Oscinella frit.In Ontario, 30–40 per cent. of frit larvae are parasitised by Hexacola in July–August and superparasitism is thus likely. Subsequent attack by Polyscelis may occur, but probably unsuccessfully.Competition between the larval parasites and the pupal ecto-parasites Callitula and Spalangia is generally slight, because the former species is not abundant and the latter tends to select only healthy hosts.Experiments are described to test the inter-relations of the three pupal parasites by exposing puparia of Drosophila melanogaster to two species simultaneously and in sequence.When Callitula and Spalangia are allowed to oviposit simultaneously, the former is more successful when hosts are relatively few, but otherwise the two species are equally successful. When Callitula parasitises puparia recently exposed to Spalangia, equal numbers of the two parasites emerge, but in the reverse experiment Callitula is superior. Callitula is able to parasitise successfully a proportion of puparia already containing Spalangia whatever the age of the latter; mature Spalangia thus attacked are mostly killed.Similar comparisons of Callitula and Spalangia with the endoparasitic Loxotropa show that Loxotropa is inferior to both the others, but that all three show marked avoidance of multiple parasitism.In general, there is little interference between the various species in the parasite complex associated with the frit-fly.The parasite complex associated with the frit-fly appears to be one that is very well balanced, there being little interference between the various species involved. Moreover, when, for any reason, one species does not attain its accustomed degree of parasitism, this is offset by an increase in the numbers of one or more of the other species.

The regions of infestation of wool by Noogoora burr (Xanthium strumarium), their climates and the biological control of the weed

1974 ◽  
Vol 25 (5) ◽  
pp. 775 ◽  
Author(s):  
AJ Wapshere
Keyword(s):  
Biological Control ◽  
North America ◽  
Indian Subcontinent ◽  
Economic Importance ◽  
The Other ◽  
Xanthium Strumarium ◽  
New Delhi ◽  
Biological Control Agents ◽  
Other Hand ◽  
Pyralid Moth

The distribution in Australia of a vegetable fault in wool caused by Noogoora burr, Xanthium stumarium, is outlined. The climates of the region in Australia where the burr produces maximum contamination of wool and where it is of the greatest economic importance are compared with the climates of North America (Texas) and the Indian subcontinent (New Delhi) from where the cerambycids, Mecas saturnina and Nupserha vexator, have been introduced respectively as biological control agents for the weed. The comparisons suggest that neither agent is climatically pre-adapted to the region in Australia where Noogoora burr has the greatest economic importance. On the other hand, a pyralid moth, Oeobia vevbascalis, from Pakistan is well adapted to the climates of the regions affected.

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