West coast North America record of the Paleogene marine stromboid gastropodRimellaand paleobiogeography of the genus

2013 ◽  
Vol 87 (5) ◽  
pp. 826-841 ◽  
Author(s):  
Richard L. Squires
Keyword(s):  
North America ◽  
West Coast ◽  
Western Europe ◽  
Middle Eocene ◽  
Late Eocene ◽  
New Combination ◽  
The West ◽  
Early Oligocene ◽  
Early Paleocene ◽  
First Time

The west coast of North America record of the shallow-marine stromboid gastropod genusRimellaAgassiz, 1841 is restudied for the first time in 90 years. This genus comprises a small group of Paleogene gastropods characterized by having an ornamented fusiform shell, a posterior canal ascending the spire, and simple (non-flared) outer lip.Rimella, whose familial ranking has been inconsistent, is placed here in family Rostellariidae Gabb, 1868, subfamily Rimellinae Stewart, 1927.EctinochilusCossmann, 1889;MacilentosClark and Palmer, 1923;VaderosClark and Palmer, 1923; andCowlitziaClark and Palmer, 1923 are recognized here as junior synonyms ofRimella. Four species are recognized from the west coast of North America: early to middle EoceneRimella macilentaWhite, 1889; early EoceneRimella oregonensisTurner, 1938; middle to late EoceneRimella supraplicata(Gabb, 1864) new combination, of whichRostellaria canaliferGabb, 1864,Cowlitizia washingtonensisClark and Palmer, 1923, andCowlitzia problematicaHanna, 1927 are recognized here as junior synonyms; and late EoceneRimella elongataWeaver, 1912.Rimellawas a warm-water gastropod whose earliest known record is of early Paleocene (Danian) age in Pakistan. Other than the west coast of North America,Rimellais found in Eocene strata in western Europe, Turkey, Egypt, Pakistan, southeastern United States, Panama, Peru, and, to a lesser degree, in Trinidad, Columbia, Java, and New Zealand. Global cooling near the end of the Eocene greatly diminished the genus. Its youngest known occurrences are of early Oligocene age in Germany, Italy, England, and Peru.

scholarly journals Tarsal morphology of ischyromyid rodents from the middle Eocene of China gives an insight into the group’s diversity in Central Asia

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Łucja Fostowicz-Frelik ◽  
Sergi López-Torres ◽  
Qian Li
Keyword(s):  
North America ◽  
Western Europe ◽  
Middle Eocene ◽  
Northern China ◽  
Taxonomic Diversity ◽  
Late Eocene ◽  
Modern Aspect ◽  
Tarsal Bones ◽  
Mammal Assemblages ◽  
First Time

AbstractIschyromyids are a group of large rodents with the earliest fossil record known from the late Paleocene (Clarkforkian) of North America; they are considered the earliest fossil representatives of Rodentia of modern aspect. Ischyromyids dominated early Paleogene small-mammal assemblages of North America and in the latest Paleocene migrated to western Europe and to Asia; in the latter they survived only to the beginning of the late Eocene, but were never abundant. Here we describe for the first time the calcanei of ischyromyids from the early middle Eocene of the Erlian Basin in Nei Mongol, northern China. These calcanei document the existence of three species. The morphology of the studied tarsal bones overall suggests ambulatory locomotion for these animals (‘slow cursors’), similar to that of the coypu and porcupines, but one form shows more marked cursorial capabilities. These differences show that Chinese ischyromyids, although rare, had attained greater taxonomic diversity by the middle Eocene in Nei Mongol than estimated from dental remains. We also address the question of the morphological and ecological divergence of these ischyromyids in relation to their North American counterparts, as well as the issue of a direct dispersal route from North America to Asia in the early Eocene.

scholarly journals Occigamasus, a new genus of pergamasine mites, with description of two new species from the west coast of North America (Parasitiformes: Gamasina: Parasitidae)

Acarologia ◽  
2019 ◽  
Vol 59 (4) ◽  
pp. 551-570
Author(s):  
Ilinca Juvara-Balş
Keyword(s):  
New Species ◽  
North America ◽  
West Coast ◽  
New Genus ◽  
Vancouver Island ◽  
New Combination ◽  
The West ◽  
Two New Species

Occigamasus n. gen., O. lindquisti n. sp. and O. makarovae n. sp. from Vancouver Island (Canada) and Oregon (U.S.A.) are described. Five other new species and their sites are noted but not enough specimens were available for adequate descriptions. Cycetogamasus californicus (Banks) sensu Hennessey and Farrier, 1988 is transferred to Occigamasus as a new combination.

scholarly journals Differing histories of Eocene angiosperm diversity in eastern North America and western Europe: dependence on paleogeography

1992 ◽  
Vol 6 ◽  
pp. 105-105
Author(s):  
Norman O. Frederiksen
Keyword(s):  
North America ◽  
Western Europe ◽  
Environmental Heterogeneity ◽  
Gulf Coast ◽  
Middle Eocene ◽  
Late Eocene ◽  
Middle Part ◽  
Eastern North America ◽  
Climatic Fluctuations ◽  
Angiosperm Pollen

Studies of Eocene angiosperm pollen floras in eastern North America (my work, especially in the eastern Gulf Coast) and western Europe (Boulter, Krutzsch) have shown significant differences in floral diversities between the two regions: in western Europe, maximum diversity was in the early Eocene and it decreased thereafter, in eastern North America, maximum diversity was in the middle part of the middle Eocene. The hypothesis presented here is that paleogeography was an important control on the diversity histories in the two regions: eastern North America was part of a large terrestrial landmass, whereas the terrestrial depositional basins of western Europe were on islands or peninsulas surrounded by the sea. Migrations between eastern and western North America were relatively easy, but migrations within what is now western Europe involved island-hopping, which explains distinct diachroneity of some angiosperm first appearances among different basins there. Western European basins were in contact with a large land mass during late Paleocene time but became isolated and smaller during the middle to late Eocene marine transgression. These changes resulted in decreased genetic exchange and increased probabilities of extinction due to (1) greater competition among species because of a reduced number of niches and (2) presence of small, isolated species populations, leading to local variations in extinctions, which probably explain the observed diachronism of taxon last appearances in different areas of Europe. Terrestrial climatic cooling in western Europe may be linked to decreasing contact between the NW European Tertiary Basin and the warm Tethys Seaway during the middle and late Eocene. In short, some combination of low environmental heterogeneity, geographic isolation, and long-term climatic deterioration probably caused the decrease in angiosperm diversity during the middle and late Eocene in western Europe.Several factors encouraged increasing or stable diversity in eastern North America but were far less effective in western Europe: (1) Eastern North America underwent greater climatic fluctuations during the Eocene (thus, immigration of taxa with different climatic preferences took place at different times), whereas the islands and peninsulas of western Europe had more uniform, maritime climates. (2) Evolution and immigration of r-selected taxa in eastern North America were favored by distinct dry seasons at certain times during the Eocene and by repeated marine transgressions and regressions that created opportunities for evolution and immigration of r-selected plants on and to freshly exposed coastal plain. In contrast, the predominantly maritime climates of western Europe in the early and middle Eocene favored K-selected plants, which had fewer possibilities for evolution and which had greater difficulty in migrating because island-hopping taxa are mainly r-selected. (3) “Arcto-Tertiary” taxa adapted to cooler climates lived and evolved in the uplands of the Appalachian Mountains, whereas western Europe was relatively flat in the Eocene –another example of its relative lack of environmental heterogeneity.

The genus Porpidia in northern and western Europe, with special emphasis on collections from the British Isles

2005 ◽  
Vol 37 (1) ◽  
pp. 1-35 ◽  
Author(s):  
Alan M. FRYDAY
Keyword(s):  
New Species ◽  
North America ◽  
Secondary Metabolite ◽  
Western Europe ◽  
Distinct Species ◽  
New Combination ◽  
Secondary Metabolite Production ◽  
British Isles ◽  
Metabolite Production ◽  
First Time

Four new species and one new forma are described in the genus Porpidia. Porpidia flavocruenta Fryday & Buschbom, a member of the P. macrocarpa group that has previously been overlooked for ‘P. flavocoerulescens’, is reported from Austria, the British Isles, Scandinavia, Iceland, and North America (Alaska); P. islandica Fryday, Knoph & Hertel is reported from Iceland and Scotland; and P. pachythallina Fryday and P. striata Fryday from the British Isles only. The sorediate morph of P. superba is described as P. superba f. sorediata Fryday, known from the British Isles, Sweden, Svalbard, and North America (Maine). Variation in P. macrocarpa is discussed and the new combination P. macrocarpa f. nigrocruenta (Anzi) Fryday made. Secondary metabolite production is discussed and the variation in the production of chemosyndromes considered to be more variable than previously reported. The position of several other taxa is discussed and P. herteliana and P. musiva are reduced to synonymy with P. cinereoatra, P. calcarea to synonymy with P. superba, and P. diversa to synonymy with P. contraponenda. However, P. grisea and P. lowiana are provisionally maintained as distinct species from P. tuberculosa and P. cinereoatra respectively, although P. grisea has not been correctly recorded from the British Isles. The typification of Spiloma tuberculosa Sm., the basionym of Porpidia tuberculosa, is discussed and a lectotype proposed; the new combination Porpidia rugosa (Taylor) Coppins & Fryday is made and shown to be the correct name for P. glaucophaea; and Porpidia flavicunda (Ach.) Gowan is used for the esorediate taxon usually known as Porpidia flavocoerulescens because this epithet is to be proposed for rejection as it is considered to be of confused usage. Porpidia hydrophila is shown to be a member of the P. albocaerulescens group. Porpidia lowiana, P. nadvornikiana, and P. thomsonii are recorded for the first time from the British Isles, and P. macrocarpa f. nigrocruenta confirmed as a British taxon. Notes and a key are provided for all the species of the genus that have been reported from the area.

New Eocene marine bivalves from Baja California Sur, Mexico

1990 ◽  
Vol 64 (3) ◽  
pp. 382-391 ◽  
Author(s):  
Richard L. Squires ◽  
Robert Demetrion
Keyword(s):  
North America ◽  
West Coast ◽  
Type Species ◽  
Baja California ◽  
Middle Eocene ◽  
Central Area ◽  
Baja California Sur ◽  
Left Valve ◽  
The West ◽  
Lower Eocene

A new genus, a new subgenus, and five new species of pterioid bivalves are described from shallow-marine faunas in the middle lower to middle Eocene Bateque Formation in the vicinity of Laguna San Ignacio to about 105 km southward, Pacific coast of Baja California Sur, Mexico. Batequeus n. gen. is a medium-sized pectinid with equally convex valves, a short byssal notch, anterior auricles smaller than the posterior ones, the left valve with numerous very closely spaced radial riblets that show the imbricated growth lines very well, the right valve with about 30 low, flat-topped radial ribs that can be grooved, and intercalary ribs on both valves. It is only known from its type species, Batequeus mezquitalensis n. sp., which is from the middle Eocene part of the Bateque Formation. Spondylus batequensis n. sp., a very spinose species, is from the middle lower Eocene part of the Bateque Formation and is only the second reported Spondylus from the lower Eocene of the west coast of North America. Pycnodonte (Phygraea) pacifica n. sp., a species characterized by a radial sulcus that originates in the umbo area, occurs in both the middle lower and middle Eocene parts of the Bateque Formation. Phygraea has not been reported previously from the west coast of North America. Pycnodonte (Pegma) n. subgen. has a plicate left valve with a large attachment area (that can cover the entire valve) and a right valve that usually has an inflated smooth central area surrounded by plicate margins. It is only known from its type species, Pycnodonte (Pegma) bajaensis n. sp., which occurs in both the middle lower and middle Eocene parts of the Bateque Formation. Cubitostrea mezquitalensis n. sp., a strongly ornamented species, is from the middle Eocene part of the Bateque Formation and is the first occurrence of this genus from the west coast of North America.

Chains to the West: Markov's Theory of Connected Events and Its Transmission to Western Europe

2006 ◽  
Vol 19 (4) ◽  
pp. 561-589 ◽  
Author(s):  
David Link
Keyword(s):  
Twentieth Century ◽  
North America ◽  
English Translation ◽  
Western Europe ◽  
Russian Mathematician ◽  
The West ◽  
Experimental Application ◽  
First Time ◽  
Empirical Material

ArgumentAt the beginning of the twentieth century, the Russian mathematician Andrey A. Markov extended the laws of the calculus of probability to trials that were dependent on each other, purely theoretically. In two articles from 1913, which are presented here in English translation, he applied his theory for the first time to empirical material, namely text. After a presentation of Markov's methods, results, and possible inspirations, the introduction investigates the dissemination of his ideas to Western Europe and North America in detail. The experimental application of his method to various types of text finally determines its scope.

Investigations of the marine algae of Nova Scotia. XI. Additional species new or rare to Nova Scotia

1973 ◽  
Vol 51 (10) ◽  
pp. 1741-1746 ◽  
Author(s):  
T. Edelstein ◽  
C. Bird ◽  
J. McLachlan
Keyword(s):  
Nova Scotia ◽  
North America ◽  
West Coast ◽  
Marine Algae ◽  
Atlantic Coast ◽  
The West ◽  
Additional Species ◽  
First Time

Twenty-one additional species new or rare to Nova Scotia are reported. Of these, 12 belong to the Rhodophyceae, 6 to the Phaeophyceae, 1 to the Chlorophyceae, and 2 to the Xanthophyceae. Acrochaetium porphyrae and Scytosiphon dotyi, two species previously known only from the west coast of North America, are recorded for the first time from the Atlantic coast of that continent. Porphyrodiscus simulons and Entonema polycladum, known from Europe, are also recorded for the first time in North America.

A new pseudolivine gastropod genus from the lower Tertiary of North America

1989 ◽  
Vol 63 (1) ◽  
pp. 38-47 ◽  
Author(s):  
Richard L. Squires
Keyword(s):  
North America ◽  
West Coast ◽  
New Genus ◽  
Gulf Coast ◽  
Late Eocene ◽  
Geographic Isolation ◽  
The West ◽  
Spiral Ribbing ◽  
Body Whorl ◽  
Upper Paleocene

A new genus, Calorebama, is proposed for a clade of pseudolivine gastropods (family Buccinidae) that has its earliest species in the lower Paleocene (Danian) of Alabama, its next earliest species in the upper Paleocene (Thanetian) of Alabama, and its subsequent species in the Eocene of California, Oregon, and Washington. Calorebama is characterized by an inflated biconical shape, a biangulate body whorl usually with strong nodes on the shoulder, and fine to medium spiral ribbing that is coarser anterior to the medial pseudolivine groove.Previously, these pseudolivines now being placed in Calorebama were assigned to the genus Pseudoliva. Study of the literature and every available museum specimen showed Calorebama to have five species and two subspecies, all of which have biostratigraphic integrity.Calorebama unicarinata (Aldrich) is the earliest species, and it, along with C. tuberculifera (Conrad), are the only known Gulf Coast species. Calorebama dilleri dilleri (Dickerson) is the earliest representative of the genus on the West Coast of North America, and it arrived during the early Eocene (Ypresian). Probable geographic isolation of C. dilleri dilleri in central and southern California resulted in lineage splitting and the appearance of C. dilleri lineata (Gabb), which phyletically evolved into C. inornata (Dickerson). Calorebama dilleri dilleri persisted in northern California and phyletically evolved into C. dilleri kirbyi (Clark), which similarly evolved into C. volutaeformis (Gabb).Calorebama inornata and C. volutaeformis, the youngest species of the genus, became widely distributed along the West Coast of North America before becoming extinct by the end of the earliest late Eocene.

Kidnapped

2014 ◽  
Author(s):  
Robert Louis Stevenson ◽  
Ian Duncan
Keyword(s):  
West Coast ◽  
Historical Novel ◽  
The Novel ◽  
The West ◽  
Scottish Highlands ◽  
Cross Country ◽  
First Time ◽  
Adventure Stories

Your bed shall be the moorcock’s, and your life shall be like the hunted deer’s, and ye shall sleep with your hand upon your weapons.’ Tricked out of his inheritance, shanghaied, shipwrecked off the west coast of Scotland, David Balfour finds himself fleeing for his life in the dangerous company of Jacobite outlaw and suspected assassin Alan Breck Stewart. Their unlikely friendship is put to the test as they dodge government troops across the Scottish Highlands. Set in the aftermath of the 1745 rebellion, Kidnapped transforms the Romantic historical novel into the modern thriller. Its heart-stopping scenes of cross-country pursuit, distilled to a pure intensity in Stevenson’s prose, have become a staple of adventure stories from John Buchan to Alfred Hitchcock and Ian Fleming. Kidnapped remains as exhilarating today as when it was first published in 1886. This new edition is based on the 1895 text, incorporating Stevenson’s last thoughts about the novel before his death. It includes Stevenson’s ‘Note to Kidnapped’, reprinted for the first time since 1922.

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