Bryozoans from the Murfreesboro and Pierce Limestones (Early Black Riveran, Middle Ordovician), Stones River Group, of Central Tennessee

1985 ◽  
Vol 59 (S15) ◽  
pp. 1-42 ◽  
Author(s):  
Olgerts L. Karklins
Keyword(s):  
New York ◽  
North America ◽  
Geographic Distribution ◽  
Species Level ◽  
Invertebrate Fauna ◽  
Middle Ordovician ◽  
Stratigraphic Ranges

The Murfreesboro Limestone and the succeeding Pierce Limestone (Black Riveran, Middle Ordovician) of the Stones River Group, the oldest rocks exposed in central Tennessee, contain a fossil invertebrate fauna including bryozoans. Bryozoans are relatively scarce in the Murfreesboro Limestone but are abundant in the overlying Pierce Limestone. The bryozoan fauna includes the cryptostomes, Escharopora, Graptodictya, Pachydictya, Phylloporina, Stictopora, Stictoporella, Trigonodictya, Ulrichostylus; the trepostomes Amplexopora, Batostoma, Hemiphragma, Nicholsonella, Parvohallopora; and the cystoporates Ceramophylla and Constellaria. These bryozoans are the oldest known in Tennessee and are the only early Black Riveran assemblage in North America described at the species level. Species of Nicholsonella, Pachydictya, and Stictopora in the Murfreesboro and species of Constellaria and Phylloporina? in the Pierce are closely related to those found in rocks of Chazyan age in New York and Vermont. Species of Ceramophylla, Escharopora, and Trigonodictya in the Pierce Limestone of central Tennessee are decidedly similar to species found in Black Riveran strata of New York. The stratigraphic ranges, geographic distribution, and taxonomy of previously described species from Tennessee are updated.

Trilobites from the base of the type Whiterockian (Middle Ordovician) in Nevada

1999 ◽  
Vol 73 (2) ◽  
pp. 182-201 ◽  
Author(s):  
Richard A. Fortey ◽  
Mary L. Droser
Keyword(s):  
New Species ◽  
North America ◽  
Turning Point ◽  
Abrupt Change ◽  
Major Change ◽  
Species Level ◽  
Western North America ◽  
Middle Ordovician ◽  
First Time ◽  
Open Shelf

No trilobite species, and very few genera, pass from the Lower (Ibexian) into the Middle Ordovician (Whiterockian), which is a turning point in Laurentian trilobite history. Trilobites from three sections exposing the base of the Whiterock Series (basal Middle Ordovician) in Nevada are described and illustrated. They are attributable to different, and generally more open-shelf, biofacies from the Bathyurid biofacies trilobites described from the Ibex area, Utah, by Fortey and Droser (1996), but include species in common, which allow correlation into the Ibexian type section. At Little Rawhide Mountain the basal Middle Ordovician is developed in Olenid biofacies, described for the first time in western North America from rocks of this age. Correlation based on species-level similarity shows that the “spike” that has been used to define the type base of the Whiterockian (and hence the Middle Ordovician) at Whiterock Canyon is at a level younger than the base of the Whiterockian assumed in recent discussions of its international correlation. The type Whiterock base correlates with the Psephosthenaspis glabrior trilobite Subzone at Ibex, well above the major change in trilobite faunas at the base of the Psephosthenaspis Zone (P. microspinosa Subzone). In all study sections there is an abrupt change of facies after trilobite Zone J, possibly associated with regression. Four new species are described: Cloacaspis tesselata, Harpillaenus rossi, Acidiphorus? lineotuberculatus, and Benthamaspis serus.

New early Paleozoic Hyolithida and Orthothecida (Hyolitha) from North America

1989 ◽  
Vol 63 (3) ◽  
pp. 302-319 ◽  
Author(s):  
John M. Malinky
Keyword(s):  
New York ◽  
Soviet Union ◽  
North America ◽  
Lower Cambrian ◽  
Type Specimens ◽  
Geographic Ranges ◽  
Upper Cambrian ◽  
The Soviet Union ◽  
The Family ◽  
Stratigraphic Ranges

Reexamination of collections of North American Hyolitha reveals the presence of several new genera and several taxa previously known only from southeastern Europe and the Soviet Union. New representatives of the family Hyolithidae in North America are Doescherina clarki n. gen. and sp. from the Upper Cambrian of Montana and Grantitheca glenisteri n. gen. and sp. from the Lower Cambrian of New York. The geographic and stratigraphic ranges of Nevadotheca Malinky are extended by placement of Hyolithes excellens Billings from the Lower Cambrian of Newfoundland and H. princeps Billings from the Lower Cambrian of Quebec in that genus, and by the occurrence of the new species N. heckeli in the Upper Cambrian of Tennessee. Diversity within the Hyolithidae is further increased by the discovery of specimens representing a new genus in the Upper Cambrian of Alberta, but that genus remains indeterminate because those specimens are not well preserved.The type lot of Hyolithes communis Billings from the Lower Cambrian of Quebec is here included under Nitoricornus Syssoiev, to which the species H. impar Ford from the Lower Cambrian of New York is also transferred. Morphology of specimens of Hyolithes quadricostatus Shaler and Foerste from the Lower Cambrian of Newfoundland requires placement under Holmitheca quadricostatus (Shaler and Foerste) and Novitatus mapesi n. sp., family Novitatidae, order Orthothecida. Formerly, Nitoricornus Syssoiev, Holmitheca Syssoiev, and Novitatus Syssoiev were known only from the Soviet Union. These occurrences extend their geographic ranges to North America. The first known representative of the family Pauxillitidae Marek in North America, Neopauxillites zlatarskii n. gen. and sp., extends the range of that family from the Ordovician of Czechoslovakia to the Lower Cambrian of Newfoundland.Overall poor preservation of type specimens of Hyolithes americanus (Hall), H. gregarius (Meek and Hayden), H. primordialis (Hall), and H. welleri Roy precludes complete diagnoses of these species and confident assignment to genus. Hyolithes americanus and H. welleri are tentatively included under Grantitheca; the other species remain under Hyolithes with question. The names of these species should not be used for new material until better preserved topotypes become available for study.

Weird things from the Middle Ordovician of North America interpreted as conulariid fragments

2002 ◽  
Vol 76 (2) ◽  
pp. 391-393 ◽  
Author(s):  
Jeffery G. Richardson ◽  
Loren E. Babcock
Keyword(s):  
New York ◽  
North America ◽  
Eastern North America ◽  
Middle Ordovician

Small phosphatic fossils recovered from acid residues of the Galena Group Middle (Ordovician) of Wisconsin were recently described by Clark et al. (1999) as weird things. Here, we report that specimens identified by those authors as Thing 3 and Thing 6 are fragments of conulariids belonging to two species that occur widely through Middle Ordovician strata of eastern North America. Similarly disintegrated, conspecific specimens from the Trenton Limestone of northwestern Indiana, and articulated, conspecific specimens from Ohio and New York, are introduced for comparison.

Ptilodictyoid Cryptostomata Bryozoa from the Middle and Upper Ordovician Rocks of Central Kentucky

1983 ◽  
Vol 57 (S14) ◽  
pp. 1-31 ◽  
Author(s):  
Olgerts L. Karklins
Keyword(s):  
New York ◽  
New Genus ◽  
Invertebrate Fauna ◽  
Upper Ordovician ◽  
Middle Ordovician ◽  
Bridge Group ◽  
Lexington Limestone

The High Bridge Group (Middle Ordovician), and the Lexington Limestone and Clays Ferry Formation (Middle and Upper Ordovician), of central Kentucky contain a diverse fossil invertebrate fauna, including cryptostome ptilodictyoids, the so-called “bifoliates,” as a distinctive element. The ptilodictyoid bryozoans there include nine species of six genera Escharopora, Graptodictya, Phyllodictya, Stictopora, Trigonodictya, and new genus Orectodictya in two families Ptilodictyidae and Rhinidictyidae. Three species are new: Escharopora eparmata, Trigonodictya cirrita, and Orectodictya pansa. Most of the species are closely related to ptilodictyoids occurring in the Middle Ordovician of New York and Minnesota. In Kentucky, Escharopora, Stictopora, and Trigonodictya occur in the oldest rocks exposed, and thus include the oldest bryozoans found in Kentucky. The stratigraphic distribution of ptilodictyoids in Kentucky reflects the disconformable contact between the Tyrone Limestone (High Bridge Group) and the overlying Lexington Limestone.

The Cainozoic to present-day record of Circum-Mediterranean, NE Atlantic and North Sea Cantharidinae and Trochinae (Trochoidea, Gastropoda)—a synopsis

Zootaxa ◽  
2021 ◽  
Vol 4902 (1) ◽  
pp. 1-81
Author(s):  
MATHIAS HARZHAUSER
Keyword(s):  
North Sea ◽  
Geographic Distribution ◽  
Fossil Record ◽  
Middle Eocene ◽  
Critical Evaluation ◽  
Species Level ◽  
Extensive Literature ◽  
Ne Atlantic ◽  
The North ◽  
Stratigraphic Ranges

Evolutionary history, diversity and (paleo)geographic distribution of Cainozoic to present-day species of the Trochidae subfamilies Cantharidinae and Trochinae are discussed based on an extensive literature survey. In total, 393 species-level taxa, assigned to 24 genera and subgenera, are listed from the NE Atlantic, the E Atlantic, the North Sea, the (Proto)-Mediterranean Sea, the Central Paratethys Sea and the Eastern Paratethys Sea. Short diagnosis and subjective and objective junior synonyms for genus-level taxa are given. Stratigraphic ranges and geographic distribution are listed for species-level taxa.                The European fossil record suggests a first major radiation during the middle Eocene and a second diversity pulse during the Miocene, when most extant genera were already present. At the species level, however, the present-day fauna is geologically very young, originating during the Pleistocene and Holocene. Overall, no convincing correlation of evolution and diversity of European Cantharidinae and Trochinae with major geodynamic events (e.g. Tethys Closure) can be observed. An exception is the somewhat overlooked spectacular radiation of Cantharidinae following the hydrological isolation of the Paratethys Sea during the late Miocene. The critical evaluation of the fossil record provides anchor points to test molecular phylogenies. A major discrepancy between both approaches appears only for Jujubinus, which suggests that Paleocene species have to be excluded from the genus.                Gibbuliculus nov. gen. is introduced as new genus for a group of Oligocene to Pleistocene species, placed so far in “Colliculus” sensu auctores non Monterosato, 1888. Anceps siminescui nov. nom, Gibbuliculus saccoi nov. nom, Gibbula tavanii nov. nom., Gibbula s.l. lovellreevei nov. nom. and Gibbula s.l. steiningeri nov. nom. are proposed as new names for the preoccupied Trochus semistriatus Siminescu & Barbu, 1940, Gibbula protumida Sacco, 1896, Gibbula minima Tavani, 1939, Trochus (Gibbula) reevei Harmer, 1923 and Trochus amedei bicincta Schaffer, 1912. 

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