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Hystrichosphaeridium cooksoniae
Hystrichosphaeridium cooksoniae Singh, 1971, p.329–330, pl.51, figs.7–8; pl.52, figs.1–4. 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: 36-50µ; length of the processes: 7-28 µm; breadth of the processes: 3-20 µm.
Affinities:
Singh, 1971, p. 330: H. cooksoni is distinct from H. deanei (Davey and Williams, 1966) which posseses a large, subconical to flesh-shaped antapical process, and many longer (15-45 Ám long), subconical to tubiform processes with terminal expansions. Lithospaeridium truncigerum (Deflandre, 1937) differs from H. cooksoni in having longitudinal striations on the processes, and wide processes which are evenly distributed on the central body. H. stellatum (Maier, 1959), is distinct in possessing narrower, equally long processes with slightly flared tips and in having an evenn distribution of the wide and narrow processes on the central body.
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: 36-50µ; length of the processes: 7-28 µm; breadth of the processes: 3-20 µm.
Affinities:
Singh, 1971, p. 330: H. cooksoni is distinct from H. deanei (Davey and Williams, 1966) which posseses a large, subconical to flesh-shaped antapical process, and many longer (15-45 Ám long), subconical to tubiform processes with terminal expansions. Lithospaeridium truncigerum (Deflandre, 1937) differs from H. cooksoni in having longitudinal striations on the processes, and wide processes which are evenly distributed on the central body. H. stellatum (Maier, 1959), is distinct in possessing narrower, equally long processes with slightly flared tips and in having an evenn distribution of the wide and narrow processes on the central body.