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I. G. Sohn

Publications and source records attributed to I. G. Sohn.

At least 19 recordsLinked to original sources
USGS2016

On the superfamily Darwinuloidacea, the type species of Darwinuloidea Mandelstam, 1956, and on the status of Cheikella Sohn and Morris, 1963 (Ostracoda)

Molostovskaja (1979, p. 54) described without illustrations the family Darwinuloididae Molostovskaja, 1979. The following year, Molostovskaja (1980, p. 33) described the family again as new [Darwinuloididae fam. nov.]. She included the genus Whipplella Holland, 1934, in the family and illustrated Darwinuloides svijazhicus (Sharapova 1948) (Molostovskaja, 1980, p. 28, figs. 5a, b, 8). Schneider (1948, p. 29, pl. 2, figs, 1a, b) originally described and illustrated this species as “ Darwinula svijazhicus Sharapova n. mns.” Two years later, Molostovskaja (1982, p. 158) illustrated cross-sections of the adductor muscle attachment scar patterns in the families of the Darwinulacea Brady and Norman, 1889. Later Molostovskaja (1990, p. 166) erected the superfamily Darwinuloidacea Molostovskaja, 1979 to include Whipplella Holland, 1934, Vymella Kalis and Mischina in Mischina and Kalis, 1975, and questionably Pruvostina Scott and Summerson, 1943. In the same paper, she illustrated Whipplella sp. (pl. 72, figs. 6a, b) [from Sohn, 1977], Vymella dobrinini (Kashevarova, 1961) (pl. 72, figs. 7a-c), Darwinuloides sentjakensis (Sharapova in Schneider, 1948) (pl. 73, figs. 5, 6), and D. svijazhicus (Sharapova in Schneider, 1948) (pl. 74, figs. 14a, b).

Journal of Paleontology↗
USGS1996

On the central muscle attachment scar pattern of Suchonella Spizharsky 1939

The fortuitous spalling of a carapace of the nonmarine Permian Suchonella typica Spizharsky 1939 disclosed the adductor muscle attachment scar as well as two accessory scars on both the right side of the steinkern and the inside of the spalled right valve. This central muscle field is illustrated and discussed. An objective list of species described in or referred to Suchonella Spizharsky 1939 is appended.

Micropaleontology↗
USGS1987

The ubiquitous ostracode Darwinula stevensoni (Brady and Robertson, 1870), redescription of the species and lectotype designation.

Darwinula stevensoni (Brady and Robertson 1870) is the type species of Darwinula, the ubiquitous living and fossil nonmarine nominate genus of the Darwinulidae and the Darwinulacea. To date, the additional families Darwinuloididae (fossil), Microdarwinulidae (living and fossil), Panxianidae (fossil), and Suchonellidae (fossil) have been referred to the Darwinulacea. A type specimen for D. stevensoni has not been previously designated. In order to stabilize the species, a lectotype is selected from the type series in the Brady collection at The Hancock Museum, Newcastle upon Tyne. The species is redescribed and reillustrated based on the study of the carapace of a paralectotype and also of valves and appendages of specimens from both England and the United States. Living species of Darwinula have a cosmopolitan distribution in fresh and brackish water. Fossil Darwinulacea, documented in the Carboniferous, serve as indicators of continental Paleozoic to Holocene deposits. - Author

Micropaleontology↗
USGS1978

Tribolbina Latham, 1932, an early Carboniferous through Permian palaeocopid ostracode genus

The type-species of Tribolbina Latham, 1932, T. carnegiei , and T. gigantea (Jones, Kirkby, and Brady, 1884) are redefined and reillustrated, and lectotypes for both are designated. T. permiana (Kellett, 1933) and T. tumida (Scott and Borger, 1941) are also redefined and reillustrated. Beyrichiana Kellett, 1933, is considered a junior subjective synonym of Tribolbina Latham, 1932. On the basis of abundant silicified specimens from the Permian of Greece, T. doescheri n. sp. is described, and T. aff. T. doescheri and T . sp. 1 are illustrated. The stratigraphic range of Tribolbina as redefined is lower Carboniferous through Permian, and its known distribution is Europe and North America where representatives lived in shallow seas. Tribolbinidae and Tribolbinecea are established as new suprageneric categories in the Palaeocopida for Tribolbina and the Silurian Kolmodinia Martinsson, 1962.

Episkopi↗
USGS1977

Radiate shell structures in Paleozoic Myodocopid and Palaeocopid ostracodes are epigenetic

The radiate structures in the shell of Paleozoic ostracodes are interpreted to be epigenetic in origin. On the basis of this interpretation, the genus Radiicypridina Bless, 1973, is a junior synonym of Eocypridina Kesling and Ploch, 1960. The type-series of Eocypridina radiata (Jones, Kirkby, and Brady, 1874), from the Coal Measures of Scotland, is illustrated, and a lectotype is designated. Eocypridina aciculata , (Scott and Summerson, 1943) is a valid species, but the more elongated specimens they identified as Cypridina radiata Jones, Kirkby, and Brady, 1874, from the same collection, belong in E. aciculata . The variation in lateral outline of specimens in the Hance Formation of Kentucky is due to the orientation of the valves in the rock.

Journal of Research of the U.S. Geological Survey↗
USGS1977

Muscle scars of late Paleozoic freshwater ostracodes from West Virginia

Different adductor muscle attachment scar patterns of the three ostracode genera Darwinula Brady and Robertson, 1885, Gutschickia Scott, 1944, and Whipplella Holland, 1934, from Pennsylvanian and Permian rocks of 'West Virginia are illustrated for the first time. Gutschickia and Whipplella have been considered as junior synonyms of Carbonita Strand, 1928, and the oldest darwinulid scar pattern previously known was from the Upper Triassic of Germany. The different patterns document the presence of Darwinula in the Pennsylvanian of the United States and indicate that Whipplella and Gutschickia are valid genera. The use of ostracodes in discriminating between Carboniferous and Permian continental sedimentary rocks should be based on restudy of the species in these genera.

West Virginia↗
USGS1974

Evidence for the presence of a heart in Paleozoic ostracodes inconclusive

The presence of a heart in some Paleozoic ostracodes has been inferred by analogy with some living myodocopids that have this organ, and an ordinal classification of the leperditiids has been proposed because of this inference. A review of the present knowledge of the internal shell structure of living myodocopids indicates that there is no basis for interpreting certain markings preserved on fossil molds and steinkerns as indicating the presence of a heart.

Journal of Research of the U.S. Geological Survey↗
USGS1969

Revision of some of Girty's invertebrate fossils from the Fayetteville Shale (Mississippian) of Arkansas and Oklahoma

J.n 1910, G. H. Girty published a paper on the fauna of the Fayetteville Shale of northern Arkansas and northeastern Oklahoma in which he described 110 new taxa of fossil invertebrates. He did not, however, designate any type specimens or divulge the localities at which •the fossils were collected, nor did he illustrate the species. The present study is designed to fill the gaps in information on some of these species and to bring them as far as possible up to date and in line with the modern scheme of classification. This report deals with the corals, pelecypods, _gastropods, trilobites, and ostracodes. It does not include the brachiopods and bryozoans. The study has been performed by specialists of the U.S. Geological Survey who are contributing separate parts to the volume.

Arkansas, Oklahoma↗