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Deflandrea lucyedwardsiae
Deflandrea lucyedwardsiae Lucas-Clark, 2006, p.192–194, pl.1, fig.16; pl.2, figs.1–9.
Holotype: Lucas-Clark, 2006, pl.2, figs.1–3.
Age: Paleocene.
Original description (Lucas-Clark, 2006):
Deflandrea lucyedwardsiae sp. nov. Plate 1, fig. 16; Plate 2, figs. 1–9.
Peridiniacean cyst sp. B, Edwards, 1980, pl. 1, fig. 10.
Holotype. Plate 2, figs. 1–3. South Carolina, Savannah River Site, core LFW-10SB, 37.26 m, sample 9103.188, slide ph g/f, CGS Zeiss Sh., coordinates 100.6 x 19.1, England Finder reference U38/1. Carnegie Museum of Natural History CM 19150.
Derivation of Name. In honor of the palynologist Lucy E. Edwards.
Diagnosis. Highly variable small to medium pale peridinioid with medium to long apical horn and two approximately equally developed short to medium antapical horns. Slender, ovoidal, peridinioid shape with varying amounts of granular ornamentation, sometimes incompletely penitabular. Periarcheopyle large and rounded, circular to ovoidal to hexa-euryform, differing from endoarcheopyle and sharing dorsal margin with endoarcheopyle.
Description. Small to medium, proximate peridiniacean, circumcavate cysts, slightly dorsoventrally compressed, with medium to long apical horn and two short to medium length antapical horns. Antapical horns approximately equal in length. Endocyst circular in outline; endophragm smooth, thicker than periphragm, not appressed to periphragm except along posterior margin of archeopyle, or may be appressed to periphragm in cingular region. Periphragm thin, outline peridinioid or rounded peridinioid, lateral margins convex, antapical margin concave. Surface minutely ornamented with scattered granules that sometimes align to form faint, longitudinal striations and are sometimes partly penitabular or may seem organized into intratabular groups. Granules may be fine or relatively coarse, numerous or sparse. Tabulation indicated by archeopyle, cingulum, and partially where some ornament is penitabular or intratabular, indicating the positions of precingular and postcingular plates. Archeopyle type I/I (2a), periarcheopyle nearly circular to ovoidal to rounded hexagonal, rarely angular hexagonal. Endoarcheopyle also circular to rounded hexagonal and sharing its posterior margin with periarcheopyle. Cingulum usually, but not always, indicated by rows of granules or denticles that give it a beaded appearance; sometimes indicated by ridges or folds in the periphragm. Sulcus indicated by break in cingulum and slight depression of the ventral hypocyst. Accumulation bodies sometimes present.
Dimensions. Length, 50–85 µm; width, 35–50 µm (10 specimens measured).
Remarks. The generic assignment is consistent with the limitations indicated by Lentin and Williams (1976) in that the species exhibits antapical horns of approximately equal length and a broad pseudoquadra to broad hexa intercalary archeopyle. The archeopyle is similar to that of Deflandrea phosphoritica in that the endoarcheopyle and periarcheopyle share a posterior edge (W. R. Evitt, oral communication, 2004). This species is abundant in the Paleocene of the Savannah River Site and in other parts of South Carolina and Georgia. It exhibits a wide range of intraspecific, gradational variation; the shape may be more rounded than the holotype, horns can be shorter, and the archeopyle rarely more angular. Surface ornamentation is variable so that the cyst may seem granular or almost smooth. The similarity of this species to others that have different geologic ranges suggests the possibility of a lineage starting with Deflandrea severnensis in the latest Cretaceous, to Spinidinium pulchrum in the earliest Paleocene, to Deflandrea lucyedwardsiae sp. nov. in the Paleocene, to Cerodinium depressum in the Early Eocene. If this is the case, the generic taxonomy is apparently artificial, and may need to be revised for the small peridinioids in general.
Comparison. Deflandrea lucyedwardsiae sp. nov. resembles Spinidinium pulchrum but has a distinctly different archeopyle; Spinidinium pulchrum has an angular archeopyle which either includes the dorsal precingular plate or has accessory sutures that extend along the edges of this precingular plate. Spindinium pulchrum also has more definitely intratabular to penitabular, spinose ornamentation, and has a reduced right antapical horn. Deflandrea lucyedwardsiae sp. nov. also resembles Deflandrea severnensis, which has much more reduced horns, a less rounded overall shape, and an angular archeopyle, probably not sharing a posterior margin with the endoarcheopyle. Cerodinium depressum has an endocyst that is wider than long, and has pronounced striae across the cingular area. Senegalinium microgranulatum has a granular endocyst and smooth periphragm with no traces of tabulation on the periphragm.
Previously Reported Occurrence. Upper part of the Clayton Formation, Porters Creek and Nanafalia formations (NP3-8) of the Chattahoochee River Valley of Western Georgia and Eastern Alabama.
Occurrence in Present Study. Rare in uppermost Lower Paleocene, Danian, lower Ellenton Formation, abundant in Upper Paleocene, upper Ellenton Formation, Savannah River Site and surrounding area, South Carolina.
Holotype: Lucas-Clark, 2006, pl.2, figs.1–3.
Age: Paleocene.
Original description (Lucas-Clark, 2006):
Deflandrea lucyedwardsiae sp. nov. Plate 1, fig. 16; Plate 2, figs. 1–9.
Peridiniacean cyst sp. B, Edwards, 1980, pl. 1, fig. 10.
Holotype. Plate 2, figs. 1–3. South Carolina, Savannah River Site, core LFW-10SB, 37.26 m, sample 9103.188, slide ph g/f, CGS Zeiss Sh., coordinates 100.6 x 19.1, England Finder reference U38/1. Carnegie Museum of Natural History CM 19150.
Derivation of Name. In honor of the palynologist Lucy E. Edwards.
Diagnosis. Highly variable small to medium pale peridinioid with medium to long apical horn and two approximately equally developed short to medium antapical horns. Slender, ovoidal, peridinioid shape with varying amounts of granular ornamentation, sometimes incompletely penitabular. Periarcheopyle large and rounded, circular to ovoidal to hexa-euryform, differing from endoarcheopyle and sharing dorsal margin with endoarcheopyle.
Description. Small to medium, proximate peridiniacean, circumcavate cysts, slightly dorsoventrally compressed, with medium to long apical horn and two short to medium length antapical horns. Antapical horns approximately equal in length. Endocyst circular in outline; endophragm smooth, thicker than periphragm, not appressed to periphragm except along posterior margin of archeopyle, or may be appressed to periphragm in cingular region. Periphragm thin, outline peridinioid or rounded peridinioid, lateral margins convex, antapical margin concave. Surface minutely ornamented with scattered granules that sometimes align to form faint, longitudinal striations and are sometimes partly penitabular or may seem organized into intratabular groups. Granules may be fine or relatively coarse, numerous or sparse. Tabulation indicated by archeopyle, cingulum, and partially where some ornament is penitabular or intratabular, indicating the positions of precingular and postcingular plates. Archeopyle type I/I (2a), periarcheopyle nearly circular to ovoidal to rounded hexagonal, rarely angular hexagonal. Endoarcheopyle also circular to rounded hexagonal and sharing its posterior margin with periarcheopyle. Cingulum usually, but not always, indicated by rows of granules or denticles that give it a beaded appearance; sometimes indicated by ridges or folds in the periphragm. Sulcus indicated by break in cingulum and slight depression of the ventral hypocyst. Accumulation bodies sometimes present.
Dimensions. Length, 50–85 µm; width, 35–50 µm (10 specimens measured).
Remarks. The generic assignment is consistent with the limitations indicated by Lentin and Williams (1976) in that the species exhibits antapical horns of approximately equal length and a broad pseudoquadra to broad hexa intercalary archeopyle. The archeopyle is similar to that of Deflandrea phosphoritica in that the endoarcheopyle and periarcheopyle share a posterior edge (W. R. Evitt, oral communication, 2004). This species is abundant in the Paleocene of the Savannah River Site and in other parts of South Carolina and Georgia. It exhibits a wide range of intraspecific, gradational variation; the shape may be more rounded than the holotype, horns can be shorter, and the archeopyle rarely more angular. Surface ornamentation is variable so that the cyst may seem granular or almost smooth. The similarity of this species to others that have different geologic ranges suggests the possibility of a lineage starting with Deflandrea severnensis in the latest Cretaceous, to Spinidinium pulchrum in the earliest Paleocene, to Deflandrea lucyedwardsiae sp. nov. in the Paleocene, to Cerodinium depressum in the Early Eocene. If this is the case, the generic taxonomy is apparently artificial, and may need to be revised for the small peridinioids in general.
Comparison. Deflandrea lucyedwardsiae sp. nov. resembles Spinidinium pulchrum but has a distinctly different archeopyle; Spinidinium pulchrum has an angular archeopyle which either includes the dorsal precingular plate or has accessory sutures that extend along the edges of this precingular plate. Spindinium pulchrum also has more definitely intratabular to penitabular, spinose ornamentation, and has a reduced right antapical horn. Deflandrea lucyedwardsiae sp. nov. also resembles Deflandrea severnensis, which has much more reduced horns, a less rounded overall shape, and an angular archeopyle, probably not sharing a posterior margin with the endoarcheopyle. Cerodinium depressum has an endocyst that is wider than long, and has pronounced striae across the cingular area. Senegalinium microgranulatum has a granular endocyst and smooth periphragm with no traces of tabulation on the periphragm.
Previously Reported Occurrence. Upper part of the Clayton Formation, Porters Creek and Nanafalia formations (NP3-8) of the Chattahoochee River Valley of Western Georgia and Eastern Alabama.
Occurrence in Present Study. Rare in uppermost Lower Paleocene, Danian, lower Ellenton Formation, abundant in Upper Paleocene, upper Ellenton Formation, Savannah River Site and surrounding area, South Carolina.