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Kiokansium sarmentum

Kiokansium sarmentum (Davey, 1979b, p.555, pl.1, figs.8–12) Davey, 1982a, p.377.

Now Kleithriasphaeridium?. Originally Bacchidinium, subsequently Kiokansium, thirdly (and now) Kleithriasphaeridium?.
Holotype: Davey, 1979, pl.1, figs. 8-9,12
Age: Aptian

Original description:
Bacchidinium sarmentum sp. nov. (Plate 1, Figures 8-12)
Derivation of name; Latin, sarmentum, twig—with reference to the distal branching of the processes.
Diagnosis: This is a thin-walled, subspherical species of Bacchidinium possessing one process per paraplate. The processes vary only slightly in size with the smallest ones occupying the sulcal region. The processes are relatively rigid and almost parallel-sided, although they do widen a little proximally where they may be striate. Distally they give rise to two to several stout spines orientated approximately parallel to the cyst wall. An archeopyle is typically present formed by the loss of a single precingular plate (3").
Holotype: MPK 1698, DSDP Leg 48, Hole 400A, Sample 69-1, 84-86 cm. Aptian, northern Bay of Biscay.
Dimensions: Central body diameter : Holotype 33 x 34 µm, Range 25 (30) 34. Process length. Holotype 10-16 µm, Range 15 (16) 16 µm (maxima)
Description: The processes average approximately 1.5 µm in width and, because they are solid, are rarely deformed. The majority of the processes are of rather similar size with the slightly larger ones occupying the pre-, post-cingular, and antapical regions. These processes typically bear six to eight distal spines and these occasionally bifurcate medially; their overall span distally may be up to 15 µm.
Remarks: B. sarmentum sp. nov. differs from B. polypes by having fewer and stouter processes. Cleistosphaeridium tribuliferum (Sarjeant, 1962a) Davey et al. 1969 differs by possessing many more processes which only give rise to two to four spines distally.
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