The bryophytes of Nachvak, northern Labrador, with additional records from Saglek

1986 ◽  
Vol 64 (9) ◽  
pp. 2028-2036 ◽  
Author(s):  
Terry A. Hedderson ◽  
Guy R. Brassard

One hundred and thirty-four species of mosses and 18 species of liverworts are reported from Nachvak Fiord and 22 mosses are reported from Saglek Fiord. Nineteen of the mosses had not previously been reported from Labrador and 49 are new to northern Labrador. Seven of the liverworts are new to Labrador. Brophyte species new to eastern North America are Anastrophyllum assimile, Hygrophypnum cochlearifolium (possibly) and Lophozia cavifolia. The record of Lophozia cavifolia represents an addition to the hepatic flora of North America (excluding Greenland). The North American distributions of Hydrogrimmia mollis, Marsupella revoluta and Trichostomum arcticum are mapped. The high incidence of disjunct species in the bryoflora of the Torngat Mountains is discussed in relation to the proposed glacial history of the area.

2013 ◽  
Vol 50 (3) ◽  
pp. 315-323 ◽  
Author(s):  
Richard L. Cifelli ◽  
Cynthia L. Gordon ◽  
Thomas R. Lipka

Multituberculates, though among the most commonly encountered mammalian fossils of the Mesozoic, are poorly known from the North American Early Cretaceous, with only one taxon named to date. Herein we describe Argillomys marylandensis, gen. et sp. nov., from the Early Cretaceous of Maryland, based on an isolated M2. Argillomys represents the second mammal known from the Arundel Clay facies of the Patuxent Formation (Lower Cretaceous: Aptian). Though distinctive in its combination of characters (e.g., enamel ornamentation consisting of ribs and grooves only, cusp formula 2:4, presence of distinct cusp on anterobuccal ridge, enlargement of second cusp on buccal row, central position of ultimate cusp in lingual row, great relative length), the broader affinities of Argillomys cannot be established because of non-representation of the antemolar dentition. Based on lack of apomorphies commonly seen among Cimolodonta (e.g., three or more cusps present in buccal row, fusion of cusps in lingual row, cusps strongly pyramidal and separated by narrow grooves), we provisionally regard Argillomys as a multituberculate of “plagiaulacidan” grade. Intriguingly, it is comparable in certain respects to some unnamed Paulchoffatiidae, a family otherwise known from the Late Jurassic – Early Cretaceous of the Iberian Peninsula.


2015 ◽  
Vol 28 (20) ◽  
pp. 8109-8117 ◽  
Author(s):  
Stephen Baxter ◽  
Sumant Nigam

Abstract The 2013/14 boreal winter (December 2013–February 2014) brought extended periods of anomalously cold weather to central and eastern North America. The authors show that a leading pattern of extratropical variability, whose sea level pressure footprint is the North Pacific Oscillation (NPO) and circulation footprint the West Pacific (WP) teleconnection—together, the NPO–WP—exhibited extreme and persistent amplitude in this winter. Reconstruction of the 850-hPa temperature, 200-hPa geopotential height, and precipitation reveals that the NPO–WP was the leading contributor to the winter climate anomaly over large swaths of North America. This analysis, furthermore, indicates that NPO–WP variability explains the most variance of monthly winter temperature over central-eastern North America since, at least, 1979. Analysis of the NPO–WP related thermal advection provides physical insight on the generation of the cold temperature anomalies over North America. Although NPO–WP’s origin and development remain to be elucidated, its concurrent links to tropical SSTs are tenuous. These findings suggest that notable winter climate anomalies in the Pacific–North American sector need not originate, directly, from the tropics. More broadly, the attribution of the severe 2013/14 winter to the flexing of an extratropical variability pattern is cautionary given the propensity to implicate the tropics, following several decades of focus on El Niño–Southern Oscillation and its regional and far-field impacts.


1976 ◽  
Vol 108 (11) ◽  
pp. 1155-1165 ◽  
Author(s):  
C. D. Dondale ◽  
J. H. Redner

AbstractThe 50 known species of North American Clubiona Latreille, 1804 are rearranged in seven species-groups as follows: trivialis group (1 Holarctic, 4 Nearctic), obesa group (11 Nearctic), reclusa group (2 Holarctic, 3 Nearctic), pallidula group (1 Holarctic), abboti group (25 Nearctic), lutescens group (1 Holarctic, 1 Nearctic), maritima group (1 Nearctic). Clubiona quebecana and C. angulata are described as new species from eastern North America. C. kuratai Roddy, 1966, originally described from the female only, is synonymized under C. chippewa Gertsch, 1941, which was originally described from the male only. C. opeongo Edwards, 1958 and C. bishopi Edwards, 1958 are redescribed, the male of the former and the female of the latter not having been previously described.


2007 ◽  
Vol 85 (3) ◽  
pp. 342-346 ◽  
Author(s):  
J. Kout ◽  
J. Vlasák

The polypore Trametes gibbosa (Pers.) Fries, common in Europe and Asia, is reported from eastern North America for the first time. Single basidiospore cultures from Pennsylvania, United States, and Quebec, Canada, were paired with each other and with cultures from the Czech Republic. The North American intercollection crosses were 60% compatible and 100% compatible with the Czech cultures. All the crosses among the Czech cultures were 100% compatible. The recent introduction of T. gibbosa to North America is suggested as a possible explanation for the limited number of mating-type alleles and subsequent incompatibility among the North American cultures.


2010 ◽  
Vol 34 (4) ◽  
pp. 419-441 ◽  
Author(s):  
Joseph S. Wilson ◽  
James P. Pitts

Understanding the timing of mountain building and desert formation events in western North America is crucial to understanding the evolutionary history of the diverse arid-adapted biota that is found there. While many different, often conflicting descriptions exist regarding geobiotic change in western North America, little work has been done to synthesize these various viewpoints. In this paper we present several case studies that illustrate the differences in the various explanations, based on geological and paleobiological data, detailing mountain uplift and desertification in western North America. The majority of the descriptions detailing mountain building in this area fall into two major periods of uplift, the Laramide uplift (∼70—50 Ma) and the Neogene uplift (∼15—2 Ma), yet it remains unclear which of these events was responsible for the formation of the modern mountains. Like the descriptions of mountain building, various accounts exist detailing the timing of desert formation. Some authors suggest that the deserts existed as far back as 15 Ma while others propose that desert formation occurred as recently as 10,000 years ago. Based on this review of the literature, we suggest that the data on Cenozoic geomorphological evolution of the North American desert landscape is still too coarse and filled with gaps to allow for the development of a robust model of landscape evolution. Instead, this work demonstrates the need for biologists studying the North American biota to realize just how problematic some of the earth history data and models are so that they can build this uncertainty into biogeographic reconstructions.


2018 ◽  
Vol 9 (2) ◽  
pp. 75-89
Author(s):  
Andrew W. Weiland ◽  
Kristen J. Gremillion

Using measurements from archaeological achenes of the extinct North American cultigen marshelder (Iva annua var. macrocarpa [S.F. Blake] R.C. Jackson), we quantitatively explore patterns of variation of fruit length and width across mid-continental North America. Linear regression shows that while achene length and width increase significantly over time (length: p-value<0.0001, b=-126.04, r2=0.1037, width: p-value<0.0001, b=-230.85, r2=0.0964), overall, regions tend to show more variation. A high incidence of phenotypic variation among domesticated marshelder as measured by coefficient of variation may be a result of introgression with wild stands. An ANOVA Tukey post-hoc analysis of archaeological site samples resulted in homogeneous subsets which correspond to region with some overlap, interpreted as a cline. These results and the low numbers of wild-sized achenes in archaeological marshelder samples of eastern Kentucky support human introduction of domesticated marshelder into this region. Marshelder in the archaeological record reflects the long-standing mixed economies of hunting-gathering and agriculture used by indigenous communities of eastern North America.


2020 ◽  
Vol 33 (16) ◽  
pp. 7101-7123 ◽  
Author(s):  
Binhe Luo ◽  
Dehai Luo ◽  
Aiguo Dai ◽  
I. Simmonds ◽  
Lixin Wu

AbstractWinter surface air temperature (SAT) over North America exhibits pronounced variability on subseasonal, interannual, decadal, and interdecadal time scales. Here, reanalysis data from 1950–2017 are analyzed to investigate the atmospheric and surface ocean conditions associated with its subseasonal to interannual variability. Detrended daily SAT data reveal a known warm west/cold east (WWCE) dipole over midlatitude North America and a cold north/warm south (CNWS) dipole over eastern North America. It is found that while the North Pacific blocking (PB) is important for the WWCE and CNWS dipoles, they also depend on the phase of the North Atlantic Oscillation (NAO). When a negative-phase NAO (NAO−) coincides with PB, the WWCE dipole is enhanced (compared with the PB alone case) and it also leads to a warm north/cold south dipole anomaly in eastern North America; but when PB occurs with a positive-phase NAO (NAO+), the WWCE dipole weakens and the CNWS dipole is enhanced. The PB events concurrent with the NAO− (NAO+) and SAT WWCE (CNWS) dipole are favored by the Pacific El Niño–like (La Niña–like) sea surface temperature mode and the positive (negative) North Pacific mode. The PB-NAO+ has a larger component projecting onto the SAT WWCE dipole during the La Niña winter than during the El Niño winter because a more zonal wave train is formed. Strong North American SAT WWCE dipoles and enhanced projections of PB-NAO+ events onto the SAT WWCE dipole component are also readily seen for the positive North Pacific mode. The North Pacific mode seems to play a bigger role in the North American SAT variability than ENSO.


2015 ◽  
Vol 47 (3) ◽  
pp. 167-182 ◽  
Author(s):  
Gary B. Perlmutter ◽  
Shirley C. Tucker ◽  
Eimy Rivas Plata ◽  
Philippe Clerc ◽  
Robert Lücking

AbstractRecently collected specimens of the crustose lichenMelaspilea demissafrom south-eastern USA have been compared with those ofMelaspileaspp. previously determined from North America. A review of both the historical and contemporary treatments of this species is provided. A lectotype was selected from the type collection ofM. demissain FH and is here proposed as it best matches incomplete citations in the original treatment. We also discuss the nomenclatural and taxonomic status of the nameOpegrapha cymbiformisvar.deformis(considered a synonym ofM. gibberulosa). North American specimens ofM. gibberulosawere found to be misidentifications, as were specimens attributed toM. lentiginosula,M. mesophlebiaandM. octomera. We therefore recommend that these species be removed from the North American lichen checklist. We also present a key to North AmericanMelaspilea.


2016 ◽  
Vol 19 ◽  
Author(s):  
Stacy Nation-Knapper

This article illuminates the existence and utility of fur trade ledgers and account books held in repositories beyond those held in the Hudson’s Bay Company Archives. While the vast holdings of the HBCA are a phenomenal resource for researchers of the North American fur trade, many smaller repositories across the continent hold fur trade sources that can complement research conducted in other institutions. Such sources can, when examined with an eye to the cultural information they contain, reveal far more about the cultural history of North America than simply the economic data for which they were created.


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