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Litosphaeridium siphoniphorum ssp. glabrum
From Fensome et al., 2019:
Litosphaeridium siphoniphorum subsp. glabrum Lucas-Clark, 1984, p.186–187, pl.1, figs.1–11; pl.2, fig.2. Holotype: Lucas-Clark, 1984,
pl.1, figs.2–3; Fauconnier and Masure, pl.53, fig.11. Age: Albian–Cenomanian.
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Original description: [Lucas-Clark, 1984]:
Litosphaeridium siphoniphorum (Cookson & Eisenack) Davey & Williams 1966 subsp. glabrum n. subsp.
Plate 1; Plate 2, fig. 2
Holotype. Plate 1, figs. 2, 3. Specimen on SEM stub L.gl.J.Clark, Stanford Palynological Laboratory.
Description. Identical to L. siphoniphorum siphoniphorum except for wall ornamentation. Periphragm smooth except for minor indentations and undulations, neither granular nor reticulate. Endophragm characterized by fine ornament of a granular to "spongy" nature which can be observed only beneath processes.
Dimensions. Holotype: overall diameter 42 μm, diameter of central body 28 μm, process length ca. 14 μm, Paratype #1: diameter of central body 25 μm, process length ca. 12 μm. Paratype #2: diameter of central body without operculum 37 μm, process length ca. 10 μm. Range: total length including apical processes 40-50 μm; diameter of central body 20-35 μm; process length 8-20 μm. Number of specimens measured, 10.
Remarks. This subspecies was first recognized and designated "subsp. glabrum" by J. S. Warren (unpublished Ph.D. dissertation, 1967, p. 205-207, pl. 18, fig. 1, 2). Another specimen which I extracted from his sample, Locality 2, Lake Berryessa, California, is illustrated in Plate 1 along with specimens from Locality 1, Rice Valley, California, and these are contrasted with specimens from the Greenhorn Formation in Kansas, which appear to more closely resemble the type specimens of L. siphoniphorum (Plate 2, figs. 1, 3, 4). Although Cookson and Eisenack (1968) remarked that specimens from the British Isles are more strongly and clearly reticulate than the type specimens from Australia, new photographs taken by L. E. Stover in 1966 (personal commun. to W. R. Evitt) of the type specimens of L. siphoniphorum show a reticulation similar to that shown in British specimens. I favor the view, therefore, that specimens described as "granular" or "reticulate" are recognizable as L. siphoniphorum subsp. siphoniphorum, while those which are smooth can be distinguished as L. siphoniphorum subsp. glabrum.
Occurrence in this paper. Localities 1 and 2, Rice Valley and Lake Berryessa. Both sequences considered to be part of Great Valley Sequence of northern California, Albian-Cenomanian.
Litosphaeridium siphoniphorum subsp. glabrum Lucas-Clark, 1984, p.186–187, pl.1, figs.1–11; pl.2, fig.2. Holotype: Lucas-Clark, 1984,
pl.1, figs.2–3; Fauconnier and Masure, pl.53, fig.11. Age: Albian–Cenomanian.
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Original description: [Lucas-Clark, 1984]:
Litosphaeridium siphoniphorum (Cookson & Eisenack) Davey & Williams 1966 subsp. glabrum n. subsp.
Plate 1; Plate 2, fig. 2
Holotype. Plate 1, figs. 2, 3. Specimen on SEM stub L.gl.J.Clark, Stanford Palynological Laboratory.
Description. Identical to L. siphoniphorum siphoniphorum except for wall ornamentation. Periphragm smooth except for minor indentations and undulations, neither granular nor reticulate. Endophragm characterized by fine ornament of a granular to "spongy" nature which can be observed only beneath processes.
Dimensions. Holotype: overall diameter 42 μm, diameter of central body 28 μm, process length ca. 14 μm, Paratype #1: diameter of central body 25 μm, process length ca. 12 μm. Paratype #2: diameter of central body without operculum 37 μm, process length ca. 10 μm. Range: total length including apical processes 40-50 μm; diameter of central body 20-35 μm; process length 8-20 μm. Number of specimens measured, 10.
Remarks. This subspecies was first recognized and designated "subsp. glabrum" by J. S. Warren (unpublished Ph.D. dissertation, 1967, p. 205-207, pl. 18, fig. 1, 2). Another specimen which I extracted from his sample, Locality 2, Lake Berryessa, California, is illustrated in Plate 1 along with specimens from Locality 1, Rice Valley, California, and these are contrasted with specimens from the Greenhorn Formation in Kansas, which appear to more closely resemble the type specimens of L. siphoniphorum (Plate 2, figs. 1, 3, 4). Although Cookson and Eisenack (1968) remarked that specimens from the British Isles are more strongly and clearly reticulate than the type specimens from Australia, new photographs taken by L. E. Stover in 1966 (personal commun. to W. R. Evitt) of the type specimens of L. siphoniphorum show a reticulation similar to that shown in British specimens. I favor the view, therefore, that specimens described as "granular" or "reticulate" are recognizable as L. siphoniphorum subsp. siphoniphorum, while those which are smooth can be distinguished as L. siphoniphorum subsp. glabrum.
Occurrence in this paper. Localities 1 and 2, Rice Valley and Lake Berryessa. Both sequences considered to be part of Great Valley Sequence of northern California, Albian-Cenomanian.