Palaeocopid and podocopid Ostracoda from the Lexington Limestone and Clays Ferry Formation (Middle and Upper Ordovician) of central Kentucky

Abstract

The Middle through lower Upper Ordovician Lexington Limestone and lower part of the Clays Ferry Formation contain an abundant and diversified ostracode fauna. More than 10,000 specimens belonging to 39 genera and 53 species have been found in 73 collections made by members of the U.

Middle Katian/lowermost Hirnantian ostracods from the Prague Basin (Czech Republic): Diversity responses to the climatic changes

“…All the specimens of W. trinoda possess only three nodes, whereas W. nodosa includes quadrinodose valves as well. Warshauer & Berdan (1982) explained this variation in the number of nodes to be Parenthatia hanamiloslavensis sp. nov. Figure 8D, E, Table 8 Holotype.…”

“…Ostracod distribution from Laurentia (Maysvillian-base of Gamachian Stage) is documented from Iowa (Spivey 1939, Levinson 1951, Missouri (Keenan 1951), Minnesota (Burr & Swain 1965, Swain 1987, Kentucky (Warshauer & Berdan 1982), from the Canadian Whittaker Formation (Copeland 1977, Copeland 1989 and Vauréal and Ellis Bay formations of Anticosti Island, Quebec (Bolton 1970;Copeland 1970Copeland , 1973Barnes & McCracken 1981), which are recently considered as probably pre-Hirnantian (more in Meidla et al 2013 and references therein). Williams et al (2001) documented ostracod assemblages of Avalonia (Pusgillian-Rawtheyan Stage) from the Cautley Mudstone Formation of northern England.…”

“…The species was originally described as Ulrichia nodosa paupera by Schmidt (1941), who erected the new subspecies of Ulrichia nodosa (Ulrich, 1890) from the Upper Ordovician of Ohio. However, based on several differences in morphology, Warshauer & Berdan (1982) assigned the North American material to the genus Warthinia Spivey, 1939. We found our material corresponding to this assignment at the generic level.…”

“…sp. Warshauer & Berdan (1982) established two species; the type species N. paupera differs from N.? sp.…”

“…The species of the genus Parenthatia Kay, 1940 of the North America region are typical of the early Katian (e.g. P. camerata Kay, 1940; P. sadievillensis Warshauer & Berdan, 1982) and the genus Parapyxionella described by Přibyl (1979) seems to be endemic in the Prague Basin.…”