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Litosphaeridium cooksoniae
Hystrichosphaeridium cooksoniae (Singh, 1971, p.329–330, pl.51, figs.7–8; pl.52, figs.1–4) Yu Jingxian and Zhang Wangping, 1980, p.112. Emendation: Duxbury, 1980, p.120, as Florentinia cooksoniae.
NOW Kleithriasphaeridium. Originally Hystrichosphaeridium, subsequently Florentinia, thirdly Litosphaeridium, fourthly (and now) Kleithriasphaeridium.
Taxonomic senior synonym: Hystrichosphaeridium (as Florentinia) mantellii, according to Below (1982c, p.8) — however, Lentin and Williams (1985, p.135) retained Florentinia cooksoniae.
Taxonomic junior synonym: Hystrichosphaeridium cylindratum, according to Harker and Sarjeant (1975, p.225–226).
Holotype: Singh, 1971, pl.51, fig.7
Paratypes: Singh, 1971
Locus typicus: Peace River, Alberta, Canada
Stratum typicum: Late Albian
Original diagnosis: Singh 1971, p. 329-330
Central body ovoidal to subspherical, bearing about 25 wide processes; reflected tabulation as specified for the genus; each reflected plate area occupied by one process; processes increasing in size towards the antapex; postcingular processes about 2 to 3 times larger than the precingular processes; antapical process wide, open distally, cylindrical with straight sides and denticulate to serrate rims; width of the broad processes from about 1/2 to equal to their length; narrow processes often slightly flared distally; length of the processes from 1/6 to 1/2 of the diameter of the central body; archeopyle apical; wall of the central body double layered; outer layer smooth to slightly granular; wall of the processes smooth to faintly fibrous.
Dimensions: Maximum dimension of the test, including the processes: 60-105 µm; length of central body: 36-67 µm; breadth of the central body: 36-50 µm; length of the processes: 7-28 µm; breadth of the processes: 3-20 µm.
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Emended description: [Duxbury, 1980]:
Florentinia cooksoniae (Singh, 1971) n. comb, emend.
PI. 7, figs. 6, 9 ; text-fig. 7
1971 Hystrichosphaeridium cooksont, Singh, pp. 329, 330, pi. 51, figs. 7, 3, pi. 52, figs. 1—4.
Emended Diagnosis: A species of Florentinia having tubular processes, one per paraplate area, which are parallel sided or slightly constricted at about 2/3 their length. The tubular processes are variable in their length and width on individual specimens with the apical ones the smallest, the precingular ones larger and the postcingular ones largest of all. Secondary tubules are often present towards, but not at, the distal process margins. Within each paraplate series, there is some variation in process breadth, presumably due to variation in size of the paraplates, so that ventral processes are generally more slender than dorsal ones. The antapical process is variable and may be very similar in length and breadth to the postcingular ones, may be equal in length to the postcingulars but narrower or may be narrower than the postcingulars and longer. The
tubular processes reflect a paratabulation of the formula 4', 6", 5"', 1"''. Slender paracingular and parasulcal processes are present in varying numbers and these usually taper to a capitate extremity but may furcate at any point along their length. Both the central body and the processes may be slightly fibrous, smooth to finely granular or finely perforate. The archeopyle is single-paraplate precingular (3") with sometimes some dislocation of the apical paraplate series.
NOW Kleithriasphaeridium. Originally Hystrichosphaeridium, subsequently Florentinia, thirdly Litosphaeridium, fourthly (and now) Kleithriasphaeridium.
Taxonomic senior synonym: Hystrichosphaeridium (as Florentinia) mantellii, according to Below (1982c, p.8) — however, Lentin and Williams (1985, p.135) retained Florentinia cooksoniae.
Taxonomic junior synonym: Hystrichosphaeridium cylindratum, according to Harker and Sarjeant (1975, p.225–226).
Holotype: Singh, 1971, pl.51, fig.7
Paratypes: Singh, 1971
Locus typicus: Peace River, Alberta, Canada
Stratum typicum: Late Albian
Original diagnosis: Singh 1971, p. 329-330
Central body ovoidal to subspherical, bearing about 25 wide processes; reflected tabulation as specified for the genus; each reflected plate area occupied by one process; processes increasing in size towards the antapex; postcingular processes about 2 to 3 times larger than the precingular processes; antapical process wide, open distally, cylindrical with straight sides and denticulate to serrate rims; width of the broad processes from about 1/2 to equal to their length; narrow processes often slightly flared distally; length of the processes from 1/6 to 1/2 of the diameter of the central body; archeopyle apical; wall of the central body double layered; outer layer smooth to slightly granular; wall of the processes smooth to faintly fibrous.
Dimensions: Maximum dimension of the test, including the processes: 60-105 µm; length of central body: 36-67 µm; breadth of the central body: 36-50 µm; length of the processes: 7-28 µm; breadth of the processes: 3-20 µm.
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Emended description: [Duxbury, 1980]:
Florentinia cooksoniae (Singh, 1971) n. comb, emend.
PI. 7, figs. 6, 9 ; text-fig. 7
1971 Hystrichosphaeridium cooksont, Singh, pp. 329, 330, pi. 51, figs. 7, 3, pi. 52, figs. 1—4.
Emended Diagnosis: A species of Florentinia having tubular processes, one per paraplate area, which are parallel sided or slightly constricted at about 2/3 their length. The tubular processes are variable in their length and width on individual specimens with the apical ones the smallest, the precingular ones larger and the postcingular ones largest of all. Secondary tubules are often present towards, but not at, the distal process margins. Within each paraplate series, there is some variation in process breadth, presumably due to variation in size of the paraplates, so that ventral processes are generally more slender than dorsal ones. The antapical process is variable and may be very similar in length and breadth to the postcingular ones, may be equal in length to the postcingulars but narrower or may be narrower than the postcingulars and longer. The
tubular processes reflect a paratabulation of the formula 4', 6", 5"', 1"''. Slender paracingular and parasulcal processes are present in varying numbers and these usually taper to a capitate extremity but may furcate at any point along their length. Both the central body and the processes may be slightly fibrous, smooth to finely granular or finely perforate. The archeopyle is single-paraplate precingular (3") with sometimes some dislocation of the apical paraplate series.