The Late Cambrian (Steptoean; Furongian) trilobite Pseudokingstonia Palmer, 1965 in North America

2009 ◽  
Vol 46 (5) ◽  
pp. 355-360
Author(s):  
Stephen R. Westrop ◽  
Jonathan M. Adrain
Keyword(s):  
North America ◽  
Great Basin ◽  
Anterior Margin ◽  
Lower Half ◽  
Anterior Border ◽  
Late Cambrian ◽  
Type Area ◽  
The Family ◽  
New Material ◽  
High Degree

The poorly known Late Cambrian (Steptoean; Furongian) genus Pseudokingstonia Palmer is revised using new material from the type area in west-central Utah. Previously undocumented features of pygidial morphology, including patterns of segmentation of the axis and pleural fields, and articulating flanges on the anterior margin, confirm that the genus is closely related to the dameselloidean Cheilocephalus Berkey and that together they constitute the family Cheilocephalidae Shaw. Pseudokingstonia is diagnosed by a high degree of cranidial and, especially, pygidial effacement, an exceedingly short anterior border on the cranidium, and steeply sloping pygidial borders. In addition to the Great Basin of Nevada and Utah, the genus is also known from Alberta, Arkansas, and Pennsylvania, and all occurrences are confined to the lower half of the late Steptoean Elvinia Zone.

The agnostoid arthropod Lotagnostus Whitehouse, 1936 (late Cambrian; Furongian) from Avalonian Cape Breton Island (Nova Scotia, Canada) and its significance for international correlation

2016 ◽  
Vol 154 (5) ◽  
pp. 1001-1021 ◽  
Author(s):  
STEPHEN R. WESTROP ◽  
ED LANDING
Keyword(s):  
Nova Scotia ◽  
North America ◽  
Debris Flow ◽  
Type Species ◽  
Cape Breton Island ◽  
Late Cambrian ◽  
Cape Breton ◽  
Type Area ◽  
Stratigraphic Succession

AbstractNew and archival collections from the Chelsey Drive Group of the Avalon terrane of Cape Breton Island, Nova Scotia, Canada, yield late Cambrian trilobites and agnostoid arthropods with full convexity that contrast with compacted, often deformed material from shale and slate typical of Avalonian Britain. Four species of the agnostoid Lotagnostus form a stratigraphic succession in the upper Furongian (Ctenopyge tumida–Parabolina lobata zones). Two species, L. ponepunctus (Matthew, 1901) and L. germanus (Matthew, 1901) are previously named; L. salteri and L. matthewi are new. Lotagnostus trisectus (Salter, 1864), the type species of the genus, is restricted to compacted material from its type area in Malvern, England. Lotagnostus americanus (Billings, 1860) has been proposed as a globally appropriate index for the base of ‘Stage 10’ of the Cambrian. All four species from Avalonian Canada are differentiated clearly from L. americanus in its type area in Laurentian North America (i.e., from debris flow blocks in Taconian Quebec). In our view, putative occurrences of L. americanus from other Cambrian continents record very different species. Lotagnostus americanus cannot be recognized worldwide, and other taxa should be sought to define the base of Stage 10, such as the conodont Eoconodontus notchhpeakensis.

Late Cambrian ptychaspidid trilobites from western Utah: implications for trilobite systematics and biostratigraphy

2005 ◽  
Vol 142 (4) ◽  
pp. 377-398 ◽  
Author(s):  
J. M. ADRAIN ◽  
S. R. WESTROP
Keyword(s):  
North America ◽  
Distinct Species ◽  
Western North America ◽  
Closely Related Species ◽  
Widespread Species ◽  
Late Cambrian ◽  
South Central ◽  
New Information ◽  
The Family ◽  
Notch Peak

The Notch Peak Formation (Late Cambrian, Sunwaptan) of western Utah yields diverse silicified trilobite faunas that provide new information on the anatomy of many taxa. The family Ptychaspididae Raymond, 1924, is represented by species of Keithiella Rasetti, 1944; Idiomesus Raymond, 1924; Euptychaspis Ulrich in Bridge, 1931; and Macronoda Lochman, 1964. At least four species are new, of which E. lawsonensis and M. notchpeakensis are named formally. Much previous work on Late Cambrian trilobites has emphasized biostratigraphic utility and the recognition of geographically widespread species. Data from new silicified collections indicate that this approach is difficult to justify because many putative ‘index species’ actually represent a plexus of closely related species whose biostratigraphic significance has yet to be determined. One such plexus is represented by E. kirki Kobayashi, 1935, whose previously reported occurrences in Texas, Oklahoma, Utah, Nevada and northern Canada record at least four distinct species. Similarly, Macronoda can now be shown to consist of at least five late Sunwaptan species in south-central and western North America.

Albian Caprinid rudists from Texas re-evaluated

2002 ◽  
Vol 76 (3) ◽  
pp. 408-423 ◽  
Author(s):  
Robert W. Scott
Keyword(s):  
North America ◽  
West Texas ◽  
Type Area ◽  
New Material

Of the 33 caprinid rudist taxa reported from Albian strata in North America, only eighteen can be recognized unequivocally because many of the earlier named species were based on incomplete, altered, and poorly described specimens that do not meet rigorous criteria of modern rudist taxonomy. New data on five older taxa, “Caprina” crassifibra Roemer, 1849; “Caprina” guadalupe Roemer, 1849; “Caprina” occidentalis Conrad, 1855; “Caprina” planata Conrad, 1855, and “Icthyosarcolites” anguis Roemer, 1888, show that these species cannot be compared to current rudist taxa nor identified with certainty and therefore they should not be used in biostratigraphic, paleoecologic, or biogeographic studies. Four other taxa are poorly known and should not be used until the types or new material can be studied. Six taxa are considered here to be junior synonyms. New material collected from Upper Albian strata in West Texas, the type area of Conrad's taxa, can be identified as Kimbleia albrittoni Perkins, 1961; Kimbleia capacis Coogan, 1973; Texicaprina vivari Palmer, 1928; and Mexicaprina cornuta Coogan, 1973. The ranges of these four taxa define three zones within Upper Albian carbonates in central and west Texas.

Texanoceras, a new neptunoceratid cephalopod genus from the Upper Pennsylvanian Graham and Caddo Creek formations in north-central Texas

2011 ◽  
Vol 85 (3) ◽  
pp. 519-523 ◽  
Author(s):  
Shuji Niko ◽  
Royal H. Mapes
Keyword(s):  
North America ◽  
Taxonomic Position ◽  
North Central ◽  
The Family ◽  
North Central Texas ◽  
Central Texas ◽  
New Material ◽  
Single Genus

A neptunoceratid cephalopod, Texanoceras jacksboroensis n. gen. n. sp., is described from the Virgilian (Upper Pennsylvanian) Graham and Caddo Creek Formations in Texas, North America. The family Neptunoceratidae was previously represented by a single genus, Tetrapleuroceras. This new material provides important emendations to the diagnostic concept of the enigmatic family including shell orientation, mature modification and siphuncular structure. Although higher taxonomic position of Neptunoceratidae is difficult to determine at present, morphologic similarities between the family and the orthoceratid (?) family Brachycycloceratidae are discussed.

The Late Cambrian (Marjuman) trilobite genus Hysteropleura Raymond from the Cow Head Group, western Newfoundland

2000 ◽  
Vol 74 (6) ◽  
pp. 1020-1030 ◽  
Author(s):  
Stephen R. Westrop ◽  
Rolf Ludvigsen
Keyword(s):  
New Species ◽  
Debris Flows ◽  
Monophyletic Group ◽  
Head Group ◽  
Parsimony Analysis ◽  
Anterior Border ◽  
Late Cambrian ◽  
Substantial Modification ◽  
New Material ◽  
Three New Species

Although known previously from only two specimens from northern Greenland, new material from Marjuman boulders in debris flows of the Cow Head Group of western Newfoundland demonstrate that Verditerrina Robison is a menomoniid trilobite that is closely related to Hysteropleura Raymond. Following a parsimony analysis using the PAUP program, Verditerrina is used at the subgeneric level to label a distinctive monophyletic group within Hysteropleura. Three new species are established for the Newfoundland material: Hysteropleura (Verditerrina) adraini, H. (V.) edgecombei and H. (V.) ramskoldi. All three species undergo substantial modification of the anterior border of the cranidium during holaspid ontogeny. Two of the species, H. (V.) adraini and H. (V.) edgecombei, develop elongate, tongue-like borders that are reminiscent of those of calymenids such as Spathocalymene Tillman.

A new species of Vorticifex (Gastropoda: Planorbidae) from late Cenozoic lake deposits, Nevada

1993 ◽  
Vol 67 (3) ◽  
pp. 370-374 ◽  
Author(s):  
James R. Firby
Keyword(s):  
New Species ◽  
Intraspecific Variation ◽  
Great Basin ◽  
Late Miocene ◽  
Late Cenozoic ◽  
Type Area ◽  
Morphologic Variation ◽  
High Degree ◽  
Lake Deposits ◽  
A New Species

A new species of planorbid gastropod, Vorticifex taylori, is described from the Late Miocene (Clarendonian) Truckee Formation at its type area in Churchill County, Nevada. Comparison with younger and older species assigned to Vorticifex indicates a high degree of morphologic variation within the genus as contrasted with relatively conservative intraspecific variation, which may reflect ecologic similarities at discrete times during the development of the Great Basin subprovince of the Basin and Range physiographic province.

Species-level phylogenetic analysis of pterocephaliids (Trilobita, Cambrian) from the Great Basin, western USA

2011 ◽  
Vol 85 (6) ◽  
pp. 1128-1153 ◽  
Author(s):  
Melanie J. Hopkins
Keyword(s):  
Phylogenetic Analysis ◽  
Great Basin ◽  
Species Level ◽  
Character State ◽  
State Transformation ◽  
Late Cambrian ◽  
The Family ◽  
Composite Section ◽  
Tree Topologies ◽  
Direct Ancestor

Considerable systematic work devoted to late Cambrian trilobites includes very little species-level phylogenetic analysis. This paper presents the phylogenetic analysis of 36 species representing eight genera assigned to the Family Pterocephaliidae that occur in the Great Basin of the western United States during the Steptoean stage (Furongian). Continuous characters are treated in four different ways: discretization using finite mixture coding, discretization using gap-weighting, “as such” using ranges of values as implemented in the phylogeny program TNT, and exclusion altogether. Results indicate that even the inclusion of only a few continuous characters dramatically increases the resolution of nodes. Despite the different treatments of continuous characters, major features of the trees are shared across all results. The subfamily Pterocephaliinae is restricted to genera which possess a concave anterior border. Relative stratigraphic placement was estimated using a composite section built in CONOP and used to scale the tree topologies and to assess stratigraphic consistency. Although previously hypothesized multispecies evolutionary series are not supported by the results, tree topology, stratigraphic distribution, and optimized character state transformation support the interpretation of several sister taxa as direct ancestor-descendent pairs.

Environmental Stability and Species Proliferation in Late Cambrian Trilobite Faunas: A Test of the Niche-Variation Hypothesis

Paleobiology ◽  
1975 ◽  
Vol 1 (2) ◽  
pp. 161-174 ◽  
Author(s):  
Jean H. Ashton ◽  
A. J. Rowell
Keyword(s):  
Species Diversity ◽  
Great Basin ◽  
Morphological Variability ◽  
Environmental Stability ◽  
Late Cambrian ◽  
Niche Variation ◽  
Coefficients Of Variation ◽  
Cambrian Trilobite ◽  
Niche Variation Hypothesis ◽  
High Degree

The “niche-variation” model predicts that increase in environmental stability should be accompanied by increase in homozygosity and reduction in morphological variability. All Late Cambrian trilobite biomeres show an increase in regional species diversity from low in the biomere toward the top. This change in diversity is believed to reflect increasing environmental stability and consequently affords the opportunity to indirectly test the “niche-variation” hypothesis in a paleontological context. Measurements were made of eight cranidial features of samples of 17 species populations from the Pterocephaliid Biomere of the Great Basin. Coefficients of variation and a multivariate analog of them failed to reveal a relationship between morphological variability and species diversity. Consideration of these data together with contradictory, but limited, informaton for other organisms suggests that the predicted decrease in genetic variability may either be absent or be readily masked in naturally occurring populations, which typically retain a high degree of genetic polymorphism. If heterozygosity is common, it would appear that accidents of geography, rather than the genetic consequences of stable or unstable environments, are among the primary factors controlling the probability of speciation.

The Inscriptions on the Gravestones in the Croatian Villages of Slovakia, Chunovo and Jarovce: The Specificity of Mixing Graphics Systems

2019 ◽  
Vol 14 (1-2) ◽  
pp. 159-173
Author(s):  
Darya Yu. Vashchenko
Keyword(s):  
Foreign Language ◽  
Ethnic Group ◽  
Ethnic Groups ◽  
Native Language ◽  
Close Contact ◽  
Funerary Monuments ◽  
Traditional Spelling ◽  
The Family ◽  
High Degree ◽  
The Village

The article discusses the inscriptions on funerary monuments from the Croatian villages of Cunovo and Jarovce, located in the South of Slovakia, near Bratislava. These inscriptions reflect the complicated sociocultural situation in the region, which is particularly specific due to the fact that this territory was included to Slovakia’s territory only after 1946, while earlier the village was part of Hungary. In addition, the local Croatian ethnic group was actively in close contact with the German and Hungarian communities. At the same time, the orthographic norms of the literary Croatian, German, Hungarian, and Slovak languages, which could potentially be owned by the authors of the inscriptions, differ in many ways, despite the Latin alphabet used on all the gravestones. All this is reflected in the tombstones, representing a high degree of mixing codes. The article identifies the main types of fusion on the monuments: separate orthograms, writing the maiden name of the deceased in the spelling of her native language, the traditional spelling of the family name. In addition, the mixing of codes can be associated with writing feminitives, also order of name and surname within the anthroponym. Moreover, the settlements themselves represent different ethnic groups coexistence within the village. Gravestones from the respective cemeteries also differ from each other in the nature of the prevailing trend of the mixing codes. In Jarovce, where the ethnic groups live compactly, fusion is often presented as a separate foreign language orthograms. In Cunovo, where the ethnic groups constitute a global conglomerate, more traditional presents for a specific family spelling of the names on the monument.

LINGULIFORM BRACHIOPODS ACROSS THE STEPTOEAN/SUNWAPTAN (LATE CAMBRIAN) “BIOMERE” BOUNDARY IN THE GREAT BASIN, USA

2017 ◽  
Author(s):  
Rebecca L. Freeman ◽  
◽  
James F. Miller ◽  
Kevin R. Evans ◽  
Damon J. Bassett
Keyword(s):  
Great Basin ◽  
Late Cambrian
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