TRIARTHRUS FROM THE UPPER ORDOVICIAN OF NEW YORK REVISITED: TAPHONOMIC, TAXONOMIC AND MORPHOMETRIC ANALYSIS OF TRIARTHRUS BECKII GREEN AND TRIARTHRUS EATONI (HALL)

2017 ◽  
Author(s):  
Shaolin Meliora Censullo ◽  
◽  
Christopher McRoberts
Keyword(s):  
New York ◽  
Morphometric Analysis ◽  
Upper Ordovician

Revised stratigraphy of the middle Simcoe Group (Ordovician, upper Sandbian–Katian) in its type area: an integrated approach

2020 ◽  
Vol 57 (1) ◽  
pp. 184-198 ◽  
Author(s):  
Timothy R. Paton ◽  
Carlton E. Brett
Keyword(s):  
New York ◽  
Integrated Approach ◽  
Early 20Th Century ◽  
Upper Ordovician ◽  
Southern Ontario ◽  
Lower Member ◽  
Type Area ◽  
Central United States ◽  
The Status ◽  
Uppermost Portion

The Upper Ordovician Bobcaygeon Formation of southern Ontario is a widespread unit that spans the Sandbian–Katian stage boundary and contains exceptionally preserved invertebrate fossil assemblages, including the famed ‘Kirkfield echinoderm fauna.’ However, the precise correlation of this interval remains poorly understood. This paper presents new data on high-resolution sequence and carbon isotope chemostratigraphy of the Bobcaygeon interval based on new quarry exposures and introduces refined definitions of unit boundaries based on allostratigraphic criteria. Sequence, chemo-, and biostratigraphic evidence indicate that the Bobcaygeon Formation represents a composite unit as it encompasses a major erosional unconformity. The Coboconk and Kirkfield formations, described in the early 20th century, were merged into a single unit, the Bobcaygeon, out of concern that the original lithostratigraphic divisions would be conflated with biostratigraphic zones of the same names. However, these biostratigraphic zones are no longer favoured, and the lower member of the Bobcaygeon is here elevated again to the status of formation (Coboconk Formation) and represents the uppermost portion of the Sandbian M4 sequence. The middle and upper members of the Bobcaygeon, herein reassigned to the Kirkfield Formation, represent the upper Sandbian to lower Katian M5A and M5B sequences recognized widely in the eastern and central United States. The term Bobcaygeon is retained and elevated to the rank of subgroup. The Kirkfield Formation is divided into three members and contacts are refined, placing a 1–2 m transgressive grainstone at the base of each sequence. These units are correlated with equivalent strata of New York and the Cincinnati Arch.

Lamottia (Favositida, Tabulata) from the Decorah Formation (Kirkfieldian, Ordovician) of Iowa

1988 ◽  
Vol 62 (3) ◽  
pp. 424-426
Author(s):  
Jeffrey C. Edwards
Keyword(s):  
New York ◽  
Thin Section ◽  
Geographic Range ◽  
Upper Ordovician ◽  
North Central ◽  
The North ◽  
Tabulate Coral ◽  
Longitudinal Pattern ◽  
Stratigraphic Range ◽  
Diagenetic Feature

The early tabulate coral Lamottia heroensis has been identified from the Ion Member of the Decorah Formation (Upper Ordovician) in northeast Iowa. This extends the stratigraphic range of this species upward from Lower Chazyan to Kirkfieldian, and extends the geographic range from the Vermont-New York border area to include the north-central Midcontinent. Thin section and SEM studies strongly support the contention that the longitudinal pattern of alternating light and dark bands observed in corallite walls reflects a primary structural grain rather than a secondary diagenetic feature.

Designation of a neotype and paraneotype for Conularina triangulata (Raymond, 1905) (Upper Ordovician, eastern North America)

2020 ◽  
Vol 94 (4) ◽  
pp. 796-797
Author(s):  
Heyo Van Iten ◽  
Mario E. Cournoyer ◽  
Michelle Coyne
Keyword(s):  
New York ◽  
North America ◽  
Late Ordovician ◽  
Quebec City ◽  
Eastern North America ◽  
Upper Ordovician ◽  
Thrust Sheet ◽  
City Formation ◽  
Early Late

Conularina triangulata (Raymond, 1905), the genotype of Conularina Sinclair, 1942, is a rare, early Late Ordovician conulariid (Cnidaria, Scyphozoa; Van Iten et al., 2006) having three sides or faces instead of four (Sinclair, 1942, fig. 9; Van Iten, 1992, text-fig. 3E). Originally described from the Valcour Formation (early Sandbian; Dix et al., 2013) on Valcour Island, New York (Sinclair, 1942), C. triangulata has since been found in laterally equivalent strata of the upper Laval Formation (‘Upper Chazy’; Sinclair, 1942) in Laval, Québec, Canada (Sinclair, 1942). From this same unit and area, Sinclair (1942) erected three new, four-sided species of Conularina (C. irrasa, C. raymondi, and C. undosa), and he erected a single four-sided species (C. narrawayi) from the Ottawa Formation (now the Sandbian–Katian Ottawa Group; Dix et al., 2013) at Tétreauville (now Gatineau), Québec. Subsequently, Jerre (1994) reported the occurrence of two species of Conularina in the Upper Ordovician of Sweden. Jerre (1994) also proposed that Eoconularia? forensis Sinclair, 1946 from the Upper Ordovician Citadelle Formation (‘Quebec City’ Formation; Sinclair, 1946) in Québec City, Québec (Promontoire de Québec thrust sheet, Appalachian Humber Zone, Allochtonous Domain; Castonguay et al., 2002) is a species of Conularina.

Trans-Pacific graptolite faunal relations: the biostratigraphic position of the base of the Cincinnatian Series (Upper Ordovician) in the standard Australian graptolite zone succession

1990 ◽  
Vol 64 (6) ◽  
pp. 992-997 ◽  
Author(s):  
Stig M. Bergström ◽  
Charles E. Mitchell
Keyword(s):  
New York ◽  
Close Correlation ◽  
Late Ordovician ◽  
Upper Ordovician ◽  
Important Species ◽  
Type Area ◽  
Cincinnatian Series ◽  
Early Late ◽  
Drill Cores

Recent studies of drill-cores and outcrops have resulted in the discovery of previously unknown, taxonomically diverse, graptolite faunas in the late Middle (Mohawkian) and early Late Ordovician (Cincinnatian) strata in the Cincinnati region, the type area of the Cincinnatian Series. These faunas contain several zonal indices and other biostratigraphically important species that are used for close correlation with the standard graptolite zone succession in New York and Quebec. The new data show that the base of the Cincinnatian Series in its type area is near the middle of the Climacograptus (Diplacanthograptus) spiniferus Zone. Significantly, about a dozen Cincinnati region graptolite species are shared with apparently coeval strata in the standard Australian graptolite zone succession in Victoria, and this key faunal evidence indicates that the base of the typical Cincinnatian corresponds to a level near the middle of the Climacograptus (Climacograptus) baragwanathi Zone (Ea2) of the Eastonian Stage. This represents a considerable revision of some recently published correlations of the basal Cincinnatian in terms of the Australian graptolite zone succession.

The Upper Ordovician trilobite Raymondites Sinclair, 1944 in North America

2015 ◽  
Vol 89 (1) ◽  
pp. 110-134 ◽  
Author(s):  
Robert E. Swisher ◽  
Stephen R. Westrop ◽  
Lisa Amati
Keyword(s):  
New York ◽  
Phylogenetic Analysis ◽  
New Species ◽  
North America ◽  
Upper Ordovician ◽  
Archival Material ◽  
Palpebral Lobe ◽  
Two New Species

AbstractThe Upper Ordovician (Sandbian–Katian) bathyurid trilobite Raymondites Sinclair is revised using new collections from Missouri and Ontario, and archival material from Illinois, Wisconsin, New York, and Ontario. Phylogenetic analysis supports monophyly of Raymondites, but recognition of this genus renders Bathyurus Billings paraphyletic. We treat Raymondites as a subgenus of Bathyurus and label the paraphylum of species traditionally assigned to the latter as Bathyurus sensu lato. Bathyurus (Raymondites) is composed of five previously named species, B. (R.) spiniger (Hall), B. (R.) longispinus (Walcott), B. (R.) ingalli (Raymond), B. (R.) bandifer Sinclair, and B. (R.) trispinosus (Wilson), and two new species, B. (R.) clochensis, and B. (R.) missouriensis; an eighth species is placed in open nomenclature. All species share tuberculate sculpture on the glabella, a relatively short palpebral lobe whose length is less than half of preoccipital glabellar length, and a pygidial outline that is well rounded posteriorly. Aside from the most basal species, B. (R.) longispinus, they also possess occipital spines and, where the pygidium is known, axial pygidial spines.

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