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Hafniasphaera goodmanii
From Fensome et al., 2019:
Hafniasphaera goodmanii Edwards, 1982, p.110,112–113, pl.1, figs.1–3,5–6,8–9. Holotype: Edwards, 1982, pl.1, figs.1–3. Originally (and now) Hafniasphaera, subsequently Spiniferites. Williams et al. (1998, p.261) retained this species in Hafniasphaera. Age: Early Eocene.
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Original description [Edwards, 1982]:
Hafniaşphaera goodmanii n. sp.
Plate 1, figures 1-3, 5, 6, 8, 9
Derivation of name: Named in honor of D.K. Goodman.
Holotype: Plate 1, figs. 1-3, R 1895 H (1b), from the Nanjemoy Formation (lower Eocene) at Popes Creek, Charles County, Maryland (loc. 20).
Diagnosis: A species of Hafniasphaera with welI-developed paratabulation and with gonal processes that are closed distally, triangular in cross-section, and formed from parasutural folds. Endophragm with a distinctive honeycomb texture, periphragm with numerous, unevenly spaced circular holes.
Description: Cysts subspherical, skolochorate, consisting of a thick endophragm marked by numerous raised pustules with circular craters or
coverings and a thinner periphragm with fewer, irregular holes; periphragm distinguishable only at paracingulum and along paraplate boundaries, where it forms parasutural folds or ridges and gonal processes; in the paracingular region, these processes may tend to fuse; paratabulation gonyaulacacean, 3, 5", Xc, 5"', 1p, 1"", may be reduced or incompletely expressed; archeopyle precingular, type P (3"" only), operculum free.
Size: Diameter of entire specimen, average 80 μm (ranges 61-100 μm); diameter of endocyst, average 61 μm (range 46-81 μm); 27 specimens measured; dimensions of holotype, entire 89 μm, endocyst 63 μm.
Remarks: The specimens from the Georgia subsurface tend to be slightly larger (by approximately 10 percent) than the Virginia-Maryland specimens and their paratabulation is not as clearly developed.
Comparisons: Hafniasphaera goodmanii n. sp. resembles Achomosphaera crassipellis (Deflandre and Cookson 1955) Stover and Evitt 1978, but differs in the nature of the processes. In H. goodmanii, the processes are triangular in cross-section and closed distally, in contrast to the rounded, open processes of A. crassipellis. Furthermore, indications of paratabulation on H. goodmanii are clearer. AIll other species of Hafniasphaera possess solid processes or processes that are circular in cross-section.
Occurrences: Outcrops of the Nanjemoy Formation (lower Eocene) in Maryland (loc. 20), subsurface (lower Eocene) in Virginia (loc. 19), subsurface in Georgia (loc. 13).
Hafniasphaera goodmanii Edwards, 1982, p.110,112–113, pl.1, figs.1–3,5–6,8–9. Holotype: Edwards, 1982, pl.1, figs.1–3. Originally (and now) Hafniasphaera, subsequently Spiniferites. Williams et al. (1998, p.261) retained this species in Hafniasphaera. Age: Early Eocene.
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Original description [Edwards, 1982]:
Hafniaşphaera goodmanii n. sp.
Plate 1, figures 1-3, 5, 6, 8, 9
Derivation of name: Named in honor of D.K. Goodman.
Holotype: Plate 1, figs. 1-3, R 1895 H (1b), from the Nanjemoy Formation (lower Eocene) at Popes Creek, Charles County, Maryland (loc. 20).
Diagnosis: A species of Hafniasphaera with welI-developed paratabulation and with gonal processes that are closed distally, triangular in cross-section, and formed from parasutural folds. Endophragm with a distinctive honeycomb texture, periphragm with numerous, unevenly spaced circular holes.
Description: Cysts subspherical, skolochorate, consisting of a thick endophragm marked by numerous raised pustules with circular craters or
coverings and a thinner periphragm with fewer, irregular holes; periphragm distinguishable only at paracingulum and along paraplate boundaries, where it forms parasutural folds or ridges and gonal processes; in the paracingular region, these processes may tend to fuse; paratabulation gonyaulacacean, 3, 5", Xc, 5"', 1p, 1"", may be reduced or incompletely expressed; archeopyle precingular, type P (3"" only), operculum free.
Size: Diameter of entire specimen, average 80 μm (ranges 61-100 μm); diameter of endocyst, average 61 μm (range 46-81 μm); 27 specimens measured; dimensions of holotype, entire 89 μm, endocyst 63 μm.
Remarks: The specimens from the Georgia subsurface tend to be slightly larger (by approximately 10 percent) than the Virginia-Maryland specimens and their paratabulation is not as clearly developed.
Comparisons: Hafniasphaera goodmanii n. sp. resembles Achomosphaera crassipellis (Deflandre and Cookson 1955) Stover and Evitt 1978, but differs in the nature of the processes. In H. goodmanii, the processes are triangular in cross-section and closed distally, in contrast to the rounded, open processes of A. crassipellis. Furthermore, indications of paratabulation on H. goodmanii are clearer. AIll other species of Hafniasphaera possess solid processes or processes that are circular in cross-section.
Occurrences: Outcrops of the Nanjemoy Formation (lower Eocene) in Maryland (loc. 20), subsurface (lower Eocene) in Virginia (loc. 19), subsurface in Georgia (loc. 13).