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Eocladopyxis tessellata
Eocladopyxis tessellata Liengjarern et al., 1980
Holotype: Liengjarern et al., 1980, pl.53, fig.6
Locus typicus: Whitecliff Bay, Isle of Wight, England
Stratum typicum: Late Eocene
Original diagnosis: Liengjarern et al., 1980, p.481
Eocladopyxis distinguished by abundant, long, solid, intratabular processes which end distally in fine spines repeatedly furcated and reflexed. The central body is moderately compressed dorso-ventrally and its ambitus is circular. Archeopyle type A+[3A]+6P. Additional sutures may occur randomly between any pair of paraplates.
Original description: Liengjarern et al., 1980, p.482
The autocyst is moderately to strongly compressed dorso-ventrally with a circular ambitus. The autophragm is scabrate and is produced into solid intratabular processes, two to four, sometimes more, per paraplate. The processes are only slightly flexible, simple, somewhat expanded proximally, circular in cross-section; distally they flare into a number of fine spines which fork repeatedly; more rarely some of the processes may end in simple bifurcations. They are more or less strongly reflexed.
The archeopyle appears to be of the type A + [3A] + 6P although it is possible that all apical plates separate in the formation of the archeopyle. Additional sutures commonly develop, apparently at random, between any other pair of paraplates, both on the epicyst and on the hypocyst.
The paratabulation formula may sometimes be determined on the basis of plate separation, and is 4", 6", 6c, ?5", 1p.v., 1"""", ?Xs. Two of the apical paraplates appear to be larger than the other two. The precingular paraplates are of roughly the same size, antero-posteriorly elongate, and pentagonal in outline. The cingular paraplates are narrow and subrectangular, and frequently bear only two processes each. The hypocyst appears to be formed by five large postcingular paraplates, a prominent posterior-ventral paraplate and an antapical paraplate, but these are only rarely evident since secondary sutures are uncommon on the hypocyst; a number of smaller sulcal paraplates also appear to be present.
Measurements. Holotype, central body diameter, 37 Ám; process length 8-15 Ám.
Range. Central body diameters 31-39x35-43 Ám; process length 4.5-10 Ám. Specimens measured--11.
Affinities:
Liengjarern et al., 1980, p.482: The solid processes, paratabulation, and archeopyle type leave no doubt as to the generic allocation of E. tessellata; however, the archeopyle is not always observable, in which case the specimens closely resemble some species of the genus Impletosphaeridium Morgenroth 1966.
E. tessellata differs from E. peniculata Morgenroth, the only other species so far allocated to the genus, in its larger size and longer processes. The process terminations in E. tessellata are more complex than in E. peniculata.
Holotype: Liengjarern et al., 1980, pl.53, fig.6
Locus typicus: Whitecliff Bay, Isle of Wight, England
Stratum typicum: Late Eocene
Original diagnosis: Liengjarern et al., 1980, p.481
Eocladopyxis distinguished by abundant, long, solid, intratabular processes which end distally in fine spines repeatedly furcated and reflexed. The central body is moderately compressed dorso-ventrally and its ambitus is circular. Archeopyle type A+[3A]+6P. Additional sutures may occur randomly between any pair of paraplates.
Original description: Liengjarern et al., 1980, p.482
The autocyst is moderately to strongly compressed dorso-ventrally with a circular ambitus. The autophragm is scabrate and is produced into solid intratabular processes, two to four, sometimes more, per paraplate. The processes are only slightly flexible, simple, somewhat expanded proximally, circular in cross-section; distally they flare into a number of fine spines which fork repeatedly; more rarely some of the processes may end in simple bifurcations. They are more or less strongly reflexed.
The archeopyle appears to be of the type A + [3A] + 6P although it is possible that all apical plates separate in the formation of the archeopyle. Additional sutures commonly develop, apparently at random, between any other pair of paraplates, both on the epicyst and on the hypocyst.
The paratabulation formula may sometimes be determined on the basis of plate separation, and is 4", 6", 6c, ?5", 1p.v., 1"""", ?Xs. Two of the apical paraplates appear to be larger than the other two. The precingular paraplates are of roughly the same size, antero-posteriorly elongate, and pentagonal in outline. The cingular paraplates are narrow and subrectangular, and frequently bear only two processes each. The hypocyst appears to be formed by five large postcingular paraplates, a prominent posterior-ventral paraplate and an antapical paraplate, but these are only rarely evident since secondary sutures are uncommon on the hypocyst; a number of smaller sulcal paraplates also appear to be present.
Measurements. Holotype, central body diameter, 37 Ám; process length 8-15 Ám.
Range. Central body diameters 31-39x35-43 Ám; process length 4.5-10 Ám. Specimens measured--11.
Affinities:
Liengjarern et al., 1980, p.482: The solid processes, paratabulation, and archeopyle type leave no doubt as to the generic allocation of E. tessellata; however, the archeopyle is not always observable, in which case the specimens closely resemble some species of the genus Impletosphaeridium Morgenroth 1966.
E. tessellata differs from E. peniculata Morgenroth, the only other species so far allocated to the genus, in its larger size and longer processes. The process terminations in E. tessellata are more complex than in E. peniculata.