Taxonomy and biostratigraphic significance of Icriodus orri Klapper and Barrick and related Middle Devonian conodont species

2016 ◽  
Vol 90 (6) ◽  
pp. 1181-1196
Author(s):  
Katarzyna Narkiewicz ◽  
Pierre Bultynck
Keyword(s):  
North American ◽  
Posterior Part ◽  
Sensu Stricto ◽  
European Part ◽  
The Other ◽  
Michigan Basin ◽  
The North ◽  
Sharp Edges ◽  
North American Craton ◽  
Distinct Morphology

AbstractThe present study of the Eifelian icriodid conodonts is based on collections from Belarus and the Michigan Basin (USA). It is here proposed that forms originally included in Icriodus orri Klapper and Barrick, 1983 can be attributed to I. retrodepressus Bultynck, 1970, Icriodus orri sensu stricto, and Icriodus michiganus new species, each displaying a distinct morphology, stratigraphical range, and geographic distribution. Icriodus retrodepressus, characterized by a triangular spindle, deep depression in its posterior part, and a well-pronounced spur and antispur, appeared in the lower partitus Zone of the lowermost Eifelian and disappeared in the upper Eifelian kockelianus Zone. Icriodus michiganus n. sp., distinguished by a lachrymiform spindle with a shallow posterior depression, ranges from the lower costatus Zone to the upper kockelianus Zone. Icriodus orri differs from the other two species by the occurrence of transverse denticle rows with lateral denticles displaying sharp edges. It ranges from the upper kockelianus Zone to the ensensis Zone of the uppermost Eifelian. Icriodus retrodepressus first occurred in the European part of the Euramerican continent and later migrated into the North American area. Icriodus michiganus n. sp. has been found in the interior part of the North American Craton and near the eastern Euramerican margin. Icriodus orri occurs in the North American interior, in British Columbia (Canada), and in the eastern part of Euramerica (Belarus). The introduction of I. retrodepressus can be related to the transgressive Choteč Event, whereas that of I. orri to a transgressive stage of the Ie eustatic cycle.

THE GENUS ALEURODISCUS (SENSU STRICTO) IN NORTH AMERICA

1964 ◽  
Vol 42 (2) ◽  
pp. 213-282 ◽  
Author(s):  
Paul Arenz Lemke
Keyword(s):  
North American ◽  
New Genus ◽  
Sensu Stricto ◽  
The Other ◽  
New Genera ◽  
Neotropical Species ◽  
The North ◽  
Natural Assemblage ◽  
Host Relationships ◽  
First Time

The basidiomycete genus Aleurodiscus Rabenh. ex J. Schroet. has been variously interpreted by several authors. In its broadest sense the genus comprises the cyphelloid and corticioid homobasidiomycetes with large basidiospores. Aleurodiscus (sensu lato), thus defined, presently consists of nearly 110 named species, which appear to be referable to about 75 accepted taxa.The present work is a taxonomic re-evaluation of the genus Aleurodiscus. Some attempt to establish specific limits for the North American Aleurodisci follows and the taxonomic position of Aleurodiscus (sensu stricto) is considered. Although particular emphasis has been devoted to the North American species, practically all of the previously described species of Aleurodiscus have been reviewed by the author. When most of the named species of Aleurodiscus are compared, they appear to form a natural assemblage on the basis of their spore amyloidity and marked affinity in microstructure. These species have been retained within the genus Aleurodiscus (sensu stricto) (TYPE SPECIES: A. amorphus (Pers. per Purt.: Fr.) J. Schroet.). Certain species formerly placed in Aleurodiscus belong elsewhere. These species remain either to be reallocated into other recognized genera or to be relegated into new genera. The taxonomy of these non-amyloid-spored species will be discussed in a subsequent paper.Only the amyloid-spored species of Aleurodiscus are accounted for in the present paper. The North American and neotropical species are described, discussed, and wherever necessary illustrated. Considerable emphasis has been placed on nomenclature and synonymy. Distribution and host relationships are mentioned and those specimens examined are cited. Five previously described species are recorded for the North American mycoflora for the first time. These include Aleurodiscus aurantius (Pers. per Fr.) J. Schroet., A. disciformis (DC. per Fr.) Pat., A. fennicus Laurila, A. lapponicus Litsch., and A. tsugae Yasuda. Five species are described as new to science: Aleurodiscus abietis Jacks, et Lemke, sp. nov.; A. laurentianus Jacks, et Lemke, sp. nov. A. macrocystidiatus Lemke, sp. nov. A. piceinus Lyon et Lemke, sp. nov.; and A. spiniger Rogers et Lemke, sp. nov. The combination Aleurodiscus lividocoeruleus (Karst.) Lemke, comb. nov. is provided. A new genus, Aleurocystidiellum Lemke, gen. nov. (MONOTYPE: A. subcruentatum (Berk. et Curt.) Lemke, gen. & comb. nov.), is proposed to accommodate an amyloid-spored species not considered to be cogeneric with the other amyloid-spored Aleurodisci. Aleurodiscus stereoides Yasuda is recognized as a facultative synonym of Aleurocystidiellum subcruentatum (Berk. et Curt.) Lemke.The amyloid-spored species of Aleurodiscus (sensu stricto) have been compared with certain of the other amyloid-spored hymenomycetes, and a key to the amyloid-spored Aleurodisci and allied genera is provided under the heading Stereaceae. A discussion of microstructure and terminology for the genus is given to facilitate the use of the key.

A re-examination of the type area of the Devono-Mississippian Cariboo Orogeny, central British Columbia

1981 ◽  
Vol 18 (12) ◽  
pp. 1767-1775 ◽  
Author(s):  
L. C. Struik
Keyword(s):  
British Columbia ◽  
North American ◽  
Volcanic Rocks ◽  
The Other ◽  
Type Locality ◽  
The Third ◽  
The North ◽  
Early Mesozoic ◽  
Type Area ◽  
North American Craton

Three tectonostratigraphic successions are established from remapping of the area near Barkerville and Cariboo River. The first, of Late Proterozoic to Cambrian sediments, was deposited on the shallow to moderately deep platformal shelf west of and derived from the exposed North American craton. The second is an unconformably overlying Ordovician to Permian sequence of sedimentary and volcanic rocks representing a basinal environment with periodic highs. These packages of sediments were deposited on the North American craton and its western transitional extensions. The third succession, composed of oceanic chert and basalt of the Permo-Pennsylvanian Antler Formation, was thrust eastward over the other two during the early Mesozoic. The three successions were folded, faulted, and metamorphosed during the mid-Mesozoic Columbian Orogeny. The Devono-Mississippian Cariboo Orogeny, which was thought to have affected all of the first sequence and part of the second, could not be documented in its type locality. The geology of the Barkerville – Cariboo River area has many similarities with that of Selwyn Basin and Cassiar platform of northern British Columbia and Yukon.

scholarly journals Eurasian and North American phylogeny of Turolian hipparionine horses (Perissodactyla, Mammalia) in China

1992 ◽  
Vol 6 ◽  
pp. 305-305
Author(s):  
Mahito Watabe
Keyword(s):  
North America ◽  
North American ◽  
Northern China ◽  
Sensu Stricto ◽  
The Other ◽  
Dental Morphology ◽  
Facial Morphology ◽  
Open Land ◽  
Specialized Form ◽  
Eastern Half

The late Miocene Chinese hipparions are morphologically diversified showing similarity to both western Old World's and North American forms. Two Chinese taxa that are phylogenetically related to western Old World's forms are Hipparion fossatum (= H. forstende) from Baode (Shanxi) and H. hippidiodus from Qingyang (Gansu) and Baode. The former is related to H. mediterraneum and the latter to H. urmiense - platygenys from the Turolian localities in the western Old World. H. fossatum and H. hippidiodus are associated with the “dorcadoides” (open-land) and “mixed” faunas in northern China. Hipparion fossatum that is characterized by POF located close to the orbit co-occurs with large and morphologically specialized form, H. dermatorhinum in Baode (Loc.30). H. hippidiodus with reduced POF is discovered with smaller H. coelophyes in Loc. 43, 44 (Baode) and Loc. 115 (Gansu).The hipparions associated with the “gaudryi” (forest) fauna are characterized by well defined and small POF located far from the orbit. Those forms are: H. platyodus from Loc. 70; H. ptychodus from Loc. 73; H. tylodus from Hsi-Liang in Yushe - Wuxiang basins; and H. sefvei from Loc. 12 at Xin-an in Henan province. H. coelophyes from Baode (Loc.43 & 44) and Qingyang (Loc. 115) also show similar facial morphology to the these forms, although it has small size and shallow POF. Those forms are similar in facial and dental morphology to Hipparion sensu stricto and some species of Cormohipparion in North America.The assemblages of Chinese hipparions are composed of two groups whose members are phylogenetically similar to the forms from both western part of Eurasia and North America. The “gaudryi” fauna is considered younger than the other two on the basis of faunal analyses. The similarity in hipparionine taxonomy between northern China and North America in the latest Miocene is an evidences for possible faunal interchange(s) occurred during that period, as suggested by taxonomic analyses on carnivores and proboscideans in eastern half of Eurasia and North America.

Paleomagnetism of the Clam Bank Formation and paleolatitude estimates for western Newfoundland

1993 ◽  
Vol 30 (4) ◽  
pp. 776-786
Author(s):  
G. Murthy ◽  
R. Pätzold
Keyword(s):  
North American ◽  
Early Paleozoic ◽  
The North ◽  
Northerly Direction ◽  
Deformation Event ◽  
Recent Origin ◽  
Component C ◽  
Acadian Orogeny ◽  
North American Craton ◽  
Devonian Age

The Pridolian Clam Bank Formation around Lourdes Cove on the Port au Port Peninsula, western Newfoundland, underwent deformation during the Acadian orogeny. As a result, some of the beds were overturned, but the stratification planes can be accurately determined everywhere. Paleomagnetic studies of the Clam Bank Formation have yielded three well-defined components of magnetization, all acquired subsequent to the deformation event: component A with D = 337.3°, I = −28.3°, (N = 16 sites, k = 25.3, α95 = 7.5°), with a corresponding paleopole at 23.2°N, 145.0°E (dp, dm = 4.5°, 8.2°); component B with D = 172.9°, I = 5.7° (N = 35 specimens, k = 10.2, α95 = 6.4°), with a corresponding paleopole at 38.2°N, 130.1°E (dp, dm = 3.2°, 6.4°); component C with D = 350.4°, I = 69.8° (N = 33 specimens, k = 8.9, α95 = 8.9°). A pre-Mesozoic origin of the A and B components is indicated by the presence of normal and reversed components in specific sites; by the lack of correspondence between the A and B paleopoles and the Mesozoic and later pole positions from the Appalachians and the North American craton; and by agreement with Paleozoic poles from the region. The A component was probably acquired immediately after deformation during the Acadian orogeny. The B component is probably a chemical remanence that was acquired during Permo-Carboniferous (Kiaman) time. The C component is of recent origin, probably acquired in the present Earth's field. Paleomagnetic data from western Newfoundland are used in a localized setting to construct a paleopole sequence and to estimate paleolatitudes for western Newfoundland during the Paleozoic. Keeping in mind the paucity of data for Siluro-Devonian age from this region, western Newfoundland seems to have been at its southernmost position at the end of the Ordovician and to have occupied equatorial latitudes during the Permo-Carboniferous. The paleolatitude trend suggests that this block, which is part of the North American craton, moved in a southerly direction during the early Paleozoic and in a northerly direction during the middle and late Paleozoic.

scholarly journals Typology and nuance: relativization

2020 ◽  
pp. 104-130
Author(s):  
Marianne Mithun
Keyword(s):  
North American ◽  
Large Scale ◽  
Relative Clauses ◽  
Spontaneous Speech ◽  
The Other ◽  
Stages Of Development ◽  
Linguistic Typology ◽  
The North

Much of linguistic typology is inherently categorical. In large-scale typological surveys, grammatical constructions, distinctions, and even variables are typically classified as present, absent, or embodying one of a set of specified options. This work is valuable for a multitude of purposes, and in many cases such categorization is sufficient. In others, we can advance our understanding further if we take a more nuanced approach, considering the extent to which a particular construction, distinction, or variable is installed in the grammar. An important tool for this approach is the examination of unscripted speech in context, complete with prosody. This point is illustrated here with Mohawk, an Iroquoian language indigenous to the North American Northeast. As will be seen, the two types of construction which might be identified as relative clauses are emergent, one less integrated into the grammar than the other. Examination of spontaneous speech indicates that the earliest stages of development are prosodic, as speakers shape their messages according to their communicative purposes at each moment.

Paleomagnetism of the Lawrenceton Formation volcanic rocks, Silurian Botwood Group, Change Islands, Newfoundland

1989 ◽  
Vol 26 (2) ◽  
pp. 296-304 ◽  
Author(s):  
Julie E. Gales ◽  
Ben A. van der Pluijm ◽  
Rob Van der Voo
Keyword(s):  
North American ◽  
Volcanic Rocks ◽  
Mobile Belt ◽  
Structural Mapping ◽  
Polar Wander ◽  
The North ◽  
Apparent Polar Wander Path ◽  
Paleomagnetic Study ◽  
North American Craton

Paleomagnetic sampling of the Lawrenceton Formation of the Silurian Botwood Group in northeastern Newfoundland was combined with detailed structural mapping of the area in order to determine the deformation history and make adequate structural corrections to the paleomagnetic data.Structural analysis indicates that the Lawrenceton Formation experienced at least two folding events: (i) a regional northeast–southwest-trending, Siluro-Devonian folding episode that produced a well-developed axial-plane cleavage; and (ii) an episode of local north-trending folding. Bedding – regional cleavage relationships indicate that the latter event is older than the regional folding.Thermal demagnetization of the Lawrenceton Formation yielded univectorial southerly and shallow directions (in situ). A fold test on an early mesoscale fold indicates that the magnetization of the Botwood postdates this folding event. However, our results, combined with an earlier paleomagnetic study of nearby Lawrenceton Formation rocks, demonstrate that the magnetization predates the regional folding. Therefore, we conclude that the magnetization occurred subsequent to the local folding but prior to the period of regional folding.While a tectonic origin for local folding cannot be entirely excluded, the subaerial nature of these volcanics, the isolated occurrence of these folds, and the absence of similar north-trending folds in other areas of eastern Notre Dame Bay suggest a syndepositional origin. Consequently, the magnetization may be nearly primary. Our study yields a characteristic direction of D = 175°, I = +43°, with a paleopole (16°N, 131 °E) that plots near the mid-Silurian track of the North American apparent polar wander path. This result is consistent with an early origin for the magnetization and supports the notion that the Central Mobile Belt of Newfoundland was adjacent to the North American craton, in its present-day position, since the Silurian.

Beyond the Cold War Chessboard

Worldview ◽  
1974 ◽  
Vol 17 (6) ◽  
pp. 21-22
Author(s):  
John W. Holmes
Keyword(s):  
United States ◽  
Cold War ◽  
North Atlantic ◽  
North American ◽  
The Other ◽  
The North ◽  
Common Interests ◽  
The North Atlantic ◽  
The Cold War

The problem in judging M. Servan-Schreiber's message is that he reaches some sound conclusions on the basis of dubious premises, from which he derives recommendations which could be disastrous.There may be some satisfaction in seeing a Frenchman concerned with le défi, russe instead of le défi américain, but his interpretation of one is as crude as was his interpretation of the other. The shock of revelation that there are common interests of the Atlantic countries in economic as well as strategic matters is understandably more startling to a Frenchman than to others. It was all set out in 1949 in Article 2 of the North Atlantic Treaty and was restated eloquently in 1973 by Mr. Kissinger. But last spring European leaders were included to see the latter as a self-interested plea from a weak United States to a prosperous Europe. The North American countries were reminded that their role in Europe was simply to defend it on request.

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