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Ceratocyrtis robustus Bj°rklund, 1976

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The test is composed of cephalis and thorax, with the hemispherical, small pored cephalis almost incorporated into the thoracic wall. The apical and ventral spines are normally very short, however, sometimes they might be quite obvious features on the cephalis (pl. 17, fig. 8). The thorax is rather thick walled, with rounded to irrgeularly rounded pores of variable size, 5-25Ám. the outline of the thorax is conical, not tapering towards the oral end (pl. 7, figs. 6 and 8). The apical spine is a pronounced feature (pl. 17, fig. 10) which, in some cases, branches out and almost reaches the lower end of the thorax. The lateral and dorsal spines do not normally pierce the thoracic wall. If they do, they are very hard to define, due to the rough and spiny upper half of the thorax (pl. 17, fig. 8). This description is based on 25 specimens.
Dimensions of holotype: Cephalis is 43Ám wide, and the height about 20Ám, defined from the top of the cephalis, to where the vertical spines pierces the thoracic wall. The greatest width of the thorax is 166Ám, while the height of the test (cephalis and thorax) is 127Ám. Holotype (pl. 17, fig. 8), from Sample 338-17, CC. The width of the 24 paratypes measured varied between 120 and 180Ám, with an average of 164Ám.
Bj°rklund 1976


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