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Litosphaeridium conispinum
Lithosphaeridium conispinum Davey and Verdier, 1973, p.193–194, pl.4, figs.4,6,8–9. Emendation: Lucas-Clark, 1984, p.187, as Litosphaeridium conispinum.
Originally (and now) Litosphaeridium, subsequently Polysphaeridium, thirdly Dapsilidinium?.
Lentin and Williams, 1981, transferred this species to Dapsilidinium Bujak et al., 1980. Lucas-Clark, 1984, retained it in Litosphaeridium.
Holotype: Davey and Verdier, 1973, pl.4, fig.8
Locus typicus: Col de Palluel, France
Stratum typicum: Late Albian
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Litosphaeridium conispinum Davey and Verdier, 1973, as emended by Lucas-Clark (1984, p.187), is skolochorate, apiculocavate with 35 to 45 processes that are hollow, discrete. Periphragm smooth except for slight undulations and pits. Three to four processes on the operculum. Processes bulbous, conical, subcylindrical or gently tapering, wide and circular at the base; constricted truncated, or closed at the tips. Often processes with a thickened rim at the tip. Process shafts circular to oval in cross-section. Processes represent B, Ci, Cu, 1u, 1i, 2-6, ai, au, b-e, fi, Iu, II-VI, X, Y, Z; one to four processes per paraplate. Cingular processes conical, closed, and smaller than pre- and postcingular processes and usually represented by two processes. Iu and Z by one each. Apical processes open or closed; pre and postcingular processes open. Operculum adnate ventrally. This species differs from other species of Litosphaeridium in the large number of processes and the small, conical closed cingular processes. Size: Central body diameter 27-48, process length 5-15 µm.
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Original diagnosis: Davey and Verdier, 1973, p. 193-194
The cyst is subspherical, possessing a smooth or coarsely gramllar, relatively thick wall from which arise thin walled, hollow processes of two types. The first type is broad, open distally and terminates with a denticulate margin; this type occupies the apical, antapical, intercalary, pre- and postcingular regions. The second process type is of an elongate conical shape, is usually closed distally and occupies the cingular and sulcal regions. The number in each region appears to be variable; the process formula, however, is 4', 6-8", 6-10c, 6-8''', 1-2p, 1'''', +/-5s.
An apical archaeopyle is always developed, with the operculum sometimes remaining attached.
Original description: Davey and Verdier, 1973, p. 194
The tubular processes may be more or less parallel sided of may taper a little distally. These processes are all of similar length on any specimen whereas the cingular and sulcal processes are more variable.
Dimensions: Range: Central body diameter 27(37)48 Ám; process length 10(12)15 Ám.
Emended description: Lucas-Clark, 1984, p. 187
Skolochorate apiculocavate cysts with subspherical to ovoid central body and a total of 35 to about 45 discrete, hollow processes (three to four on operculum). Periphragm smooth except for slight undulations and pits. Endophragm ornament, which is finely granular, visible only beneath processes.
Processes bulbous, conical, sub-cylindrical or gently tapering, wide and circular at the base; constricted, truncated, or closed at the tips. Open processes usually with a thickened rim at tip. Process shafts circular to oval in cross-section. Processes represent B, Ci, Cu, lu, li, 2-6, ai, au, b-e, fi, Iu, II-VI, X, Y, and Z; one to four processes per paraplate. Cingular processes conical, closed, and smaller than pre- and postcingular processes, and usually represented by two processes, Iu and Z by one each. Apical processes open or closed; pre- and postcingular processes open. Archeopyle apical; operculum adnate ventrally.
Affinities:
Davey and Verdier, 1973, p. 194: The overall appearance is similar to to that of L. siphoniphorum. They differ significantly in that the latter only rarely possesses closed sulcal processes and never cingular processes, has a constant number of tubular processes and possesses three apical processes.
Originally (and now) Litosphaeridium, subsequently Polysphaeridium, thirdly Dapsilidinium?.
Lentin and Williams, 1981, transferred this species to Dapsilidinium Bujak et al., 1980. Lucas-Clark, 1984, retained it in Litosphaeridium.
Holotype: Davey and Verdier, 1973, pl.4, fig.8
Locus typicus: Col de Palluel, France
Stratum typicum: Late Albian
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Litosphaeridium conispinum Davey and Verdier, 1973, as emended by Lucas-Clark (1984, p.187), is skolochorate, apiculocavate with 35 to 45 processes that are hollow, discrete. Periphragm smooth except for slight undulations and pits. Three to four processes on the operculum. Processes bulbous, conical, subcylindrical or gently tapering, wide and circular at the base; constricted truncated, or closed at the tips. Often processes with a thickened rim at the tip. Process shafts circular to oval in cross-section. Processes represent B, Ci, Cu, 1u, 1i, 2-6, ai, au, b-e, fi, Iu, II-VI, X, Y, Z; one to four processes per paraplate. Cingular processes conical, closed, and smaller than pre- and postcingular processes and usually represented by two processes. Iu and Z by one each. Apical processes open or closed; pre and postcingular processes open. Operculum adnate ventrally. This species differs from other species of Litosphaeridium in the large number of processes and the small, conical closed cingular processes. Size: Central body diameter 27-48, process length 5-15 µm.
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Original diagnosis: Davey and Verdier, 1973, p. 193-194
The cyst is subspherical, possessing a smooth or coarsely gramllar, relatively thick wall from which arise thin walled, hollow processes of two types. The first type is broad, open distally and terminates with a denticulate margin; this type occupies the apical, antapical, intercalary, pre- and postcingular regions. The second process type is of an elongate conical shape, is usually closed distally and occupies the cingular and sulcal regions. The number in each region appears to be variable; the process formula, however, is 4', 6-8", 6-10c, 6-8''', 1-2p, 1'''', +/-5s.
An apical archaeopyle is always developed, with the operculum sometimes remaining attached.
Original description: Davey and Verdier, 1973, p. 194
The tubular processes may be more or less parallel sided of may taper a little distally. These processes are all of similar length on any specimen whereas the cingular and sulcal processes are more variable.
Dimensions: Range: Central body diameter 27(37)48 Ám; process length 10(12)15 Ám.
Emended description: Lucas-Clark, 1984, p. 187
Skolochorate apiculocavate cysts with subspherical to ovoid central body and a total of 35 to about 45 discrete, hollow processes (three to four on operculum). Periphragm smooth except for slight undulations and pits. Endophragm ornament, which is finely granular, visible only beneath processes.
Processes bulbous, conical, sub-cylindrical or gently tapering, wide and circular at the base; constricted, truncated, or closed at the tips. Open processes usually with a thickened rim at tip. Process shafts circular to oval in cross-section. Processes represent B, Ci, Cu, lu, li, 2-6, ai, au, b-e, fi, Iu, II-VI, X, Y, and Z; one to four processes per paraplate. Cingular processes conical, closed, and smaller than pre- and postcingular processes, and usually represented by two processes, Iu and Z by one each. Apical processes open or closed; pre- and postcingular processes open. Archeopyle apical; operculum adnate ventrally.
Affinities:
Davey and Verdier, 1973, p. 194: The overall appearance is similar to to that of L. siphoniphorum. They differ significantly in that the latter only rarely possesses closed sulcal processes and never cingular processes, has a constant number of tubular processes and possesses three apical processes.