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Tholospyris gephyristes Hülsemann, 1963

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Tholospyris gephyristes:
The shell consists of bilocular cephalis with unequal, rounded pores and a small, fenestrated conical cupola which is prolonged into an apical spine. Three basal feet are prolongations of the dorsal and the paired lateral spines of the inner skeleton. Between their proximal portions a small amount of lattice-work connecting the spines may be present. From the lower part of the sagittal ring, where it is incorporated in the shell wall, arises a small vertical spine. There is a spine in the sagittal constriction on the dorsal side right below the cupola, like an elongation of the sagittal ring to the dorsal side. Another spine arises above the sagittal constriction on the ventral side; this spine does not originate in the constriction, but from a columella bridging the shallow groove. Haeckel (1887) shows a similar slender, bridge-like columella on the ventral side of T. tripodiscus (Pl. 89, Fig. 1), but no spine originate from there. Further, the insignificant cupola and small size of the new species, which is only about one-third of T. tripodiscus, distinguish the two species.

Dimensions. Two specimens: height of sagittal ring 0.032, 0.035mm; length of cephalis 0.044, 0.047mm.
Hülsemann 1963


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