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W. A. Oliver

Publications and source records attributed to W. A. Oliver.

9 recordsLinked to original sources
USGS2015

Nomenclatural problems of Breviphrentis stumm, 1949 and Contophrentis new genus (Devonian rugose corals)

The siphonophrentidae is a family of Devonian rugose corals that are known mostly from eastern North America, a part of the Eastern Americas biogeographical Realm (EAR) during the Devonian. Breviphrentis Stumm, 1949, has been considered a siphonophrentid by most previous authors and, in a recent monograph (Oliver, 1993), I described three EAR species as Breviphrentis and referred others to the genus.

Journal of Paleontology↗
USGS2007

Zaphrentis and the Zaphrentidae (Devonian; anthozoa, rugosa)

Zaphrentis is one of the most widely used names in Paleozoic coral paleontology. Species of "Zaphrentis" have been named from every Paleozoic System except the Cambrian. Variants of the word, such as zaphrentoid, are widely used with varied meanings. Nomenclatural spinoffs are numerous: Neozaphrentis and Heterophrentis are obvious examples, but dozens of additional genera have type species that were originally described in Zaphrentis. Many paleontologists are familiar with the word but few really know what it means. Zaphrentis (as a subgenus) and five new species were named in 1820, based on corals from the Falls of the Ohio River between Louisville, Kentucky, and Clarksville, Indiana. Descriptions were minimal, none was illustrated, and no specimens were preserved as types. Nominal species of "Zaphrentis" proliferated for over 100 years before a redescription based on Falls specimens was published (1938), the probable source beds recognized (1942), a neotype selected (1965) and adequately described and illustrated (1981). At this time, I recognize only four zaphrentid genera: Zaphrentis (middle Eifelian), Heliophyllum (middle Emsian through Givetian), Aemulophyllum (middle Emsian), and Cyathocylindrium (lower Emsian?; middle Emsian through Eifelian). All four genera seem to have originated in the Eastern Americas Biogeographic Realm. Heliophyllum is the most common, has the longest stratigraphic range, and is the only one known to occur outside of its area of origin. Heliophyllum modicum n. sp., once discussed as a possible Zaphrentis, is described and compared with both the type species of Zaphrentis and other Heliophyllum species. A single coral specimen from the Indian Cove Formation (upper Pragian or lower Emsian), Gaspe??, Quebec, is considered the earliest known zaphrentid and is described as Cyathocylindrium? n. sp.

Bulletins of American Paleontology↗
USGS2000

Stage boundary recognition in the Eastern Americas realm based on rugose corals

Most Devonian stages contain characteristic coral assemblages but these tend to be geographically and facies limited and may or may not be useful for recognising stage boundaries. Within eastern North America, corals contribute to the recognition of two boundaries: the base of the Lochkovian (Silurian-Devonian boundary) and the base of the Eifelian (Lower-Middle Devonian Series boundary).

CFS Courier Forschungsinstitut Senckenberg↗
USGS1997

Origins and relationships of colonial Heliophyllum in the upper Middle Devonian (Givetian) of New York

Heliophyllum halli Milne-Edwards and Haime is common to abundant in many Lower and Middle Devonian stratigraphic units in New York. Most Heliophyllum are solitary, but both branching and massive colonies are known. Four 'populations' of colonial Heliophyllum in the Givetian part of the sequence are distinct, as is a fifth form that occurs through the section. Each of the colonial forms is interpreted as an independent derivative of solitary forms of H. halli. The relationships appear to range from infrasubspecific to specific, and it is suggested that the complex should be recognized as the Heliophyllum halli species group.

Boletin - Real Sociedad Espanola de Historia Natur↗
USGS1991

Defining the Devonian: 1979-89

Describes the work of the Subcommission on Devonian Stratigraphy which has attempted to achieve consensus on each of the Devonian boundaries, based mainly on biostratigraphic information. The base of the Devonian system and each of the Devonian stages are defined. -S.J.Stone

Lethaia↗
USGS1990

Extinctions and migrations of Devonian rugose corals in the Eastern Americas Realm

Detailed plotting of the stratigraphic ranges of Devonian rugose coral genera within the Eastern Americas Realm reveals new information about the extinctions and migrations of this largely endemic fauna. There were significant faunal turnovers in the Lochkovian, middle Eifelian and late Givetian, as well as in the often discussed late Frasnian. The late Givetian turnover was nearly as great as the Frasnian one. Inward migration was principally from western North America, and the greatest influxes were during the early Givetian and Frasnian. It seems likely that there were several separate incursions and that some genera were introduced to the east two, or even three times.

Lethaia↗
USGS1977

Biogeography of late Silurian and devonian rugose corals

Three marine benthic faunal realms can be recognized in the Early and Middle Devonian. The Eastern Americas Realm consisted of most of the eastern half of North America and South America north of the Amazon. This realm extended in a southwest direction from the Devonian equator to approximately 35??S and was an isolated epicontinental sea during much of its history. The Eastern Americas Realm was bounded on the west by the Transcontinental Arch, on the north by the Canadian Shield and on the east and southeast by a peninsular extension of the Old Red Continent. These barriers were emergent during much, but not all, of Devonian time. Seaways beyond these barriers belonged to the Old World Realm. The Malvinokaffric Realm that was farther south was apparently temperate to arctic in climate and latitudinal position and contained few corals. Rugose corals in the Eastern Americas Realm show increasing generic-level endemism from the Late Silurian through the Early Devonian; during the late Early Devonian, 92% of the rugosan genera are not known anywhere else in the world. Endemism decreased through the Middle Devonian to zero in the early Late Devonian. The Early Devonian increase in endemism paralleled, and was probably related to, the development of the Old Red Continent as a barrier between America and Africa-Europe. The waning of endemism in the Middle Devonian reflects the breaching of the land barriers. This permitted some migration in and out of the realm in early Middle Devonian time but greatest movements were in late Middle Devonian time. Principal migration directions were from western or Arctic North America into the Michigan-Hudson Bay area and from the southern Appalachian area into Africa. ?? 1977.

Palaeogeography, Palaeoclimatology, Palaeoecology↗