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Hystrichosphaeridium ohioense
Hystrichosphaeridium ohioense Winslow, 1962
Now Gorgonisphaeridium. Originally Hystrichosphaeridium, subsequently Baltisphaeridium, thirdly (and now) Gorgonisphaeridium.
Holotype: Winslow, 1962, pl.22, fig.9
Age: Late Devonian
Original description Winslow, 1962
Diagnosis. Body spherical, subcircular and with narrow arcuate folds when compressed, 32µ-69µ, usually
greater than 45µ, in diameter. Spines numerous (35-50), subequal, slightly curved, 2µ-3.5µ broad basally, tapering uniformly to a sharp point, 8µ-21µ long. Wall smooth, 1µ-1.8µ thick, light yellow to bright yellowby transmitted light. Holotype. Plate 22, figure 9, from the Chagrin shale, locality 6, maceration 419, slide 5.
Discussion. These microfossils are quite similar to those described from the Silurian rocks of the Baltic
area as Hystrichosphaeridium brevispinosum (Ovum hispidum brevispinosum Eisenack, 1931, p. Ill) but,
instead of having spines with rounded tips, those of the Ohio shale have sharp, distinctly pointed, spines.
Neither Bashnagel (1942) nor Fisher (1953) report similar forms. Apparently the species from Ohio is distinct.
Occurrence. Very common in the Ohio shale or itsequivalent at localities 6-8 and 10, the Bedford shale at locality 2, and the Bedford shale and Berea sandstone at locality 9 (pl. 23).
Now Gorgonisphaeridium. Originally Hystrichosphaeridium, subsequently Baltisphaeridium, thirdly (and now) Gorgonisphaeridium.
Holotype: Winslow, 1962, pl.22, fig.9
Age: Late Devonian
Original description Winslow, 1962
Diagnosis. Body spherical, subcircular and with narrow arcuate folds when compressed, 32µ-69µ, usually
greater than 45µ, in diameter. Spines numerous (35-50), subequal, slightly curved, 2µ-3.5µ broad basally, tapering uniformly to a sharp point, 8µ-21µ long. Wall smooth, 1µ-1.8µ thick, light yellow to bright yellowby transmitted light. Holotype. Plate 22, figure 9, from the Chagrin shale, locality 6, maceration 419, slide 5.
Discussion. These microfossils are quite similar to those described from the Silurian rocks of the Baltic
area as Hystrichosphaeridium brevispinosum (Ovum hispidum brevispinosum Eisenack, 1931, p. Ill) but,
instead of having spines with rounded tips, those of the Ohio shale have sharp, distinctly pointed, spines.
Neither Bashnagel (1942) nor Fisher (1953) report similar forms. Apparently the species from Ohio is distinct.
Occurrence. Very common in the Ohio shale or itsequivalent at localities 6-8 and 10, the Bedford shale at locality 2, and the Bedford shale and Berea sandstone at locality 9 (pl. 23).