| Home> Cenozoic> Miocene>
 

List species

Corythospyris fiscella Goll, 1978

Description - Add description

Sagittal ring small, subcircular, somewhat D-shaped; 38 to 54Ám high; 30 to 38Ám thick; joined directly to front apex, and back to sagittal ring. Vertical spine short, obscure, arises low on the sagittal ring. Simple apical spine slender, 4 to 10 Ám long, barely visible or incomplete on many specimens. Small axobate faintly visible by bright-field illumination. Frontal bar, primary and secondary lateral bars joined to basal ring.
Basal ring oval, slightly constricte sagitally and laterally, 39 to 52Ám wide, 33 to 40 Ám thick, joined to frontal bar and directly to back of sagittal ring, and encloses three pairs of basal pores. Prominence of secondary lateral pores in front view more distinct than on specimens of Corythospyris jubata. Lattice shell 40 to 53Ám high, 60 to 77Ám wide, and slightly constricted by sagittal ring. Lattice shell does not extend below basal ring on most specimens. A few specimens have small plate of lattice below the back of basal ring which frames a single sternal pore. Three slender basal lattice spines project obliquely from basal ring at the positions of the frontal and primary lateral bars. These basal lattice spines are 12 to 20Ám long, taper to a simple point on most specimens. A few individuals have longer basal lattice spines with a symmetrical pair of short by-spines near the distal end which imparts a "trident" appearance.Lattice shell smooth, thin-walled, densely perforated by subcircular lattice pores 3 to 28Ám in diameter. These lattice pores are irregularly distributed except for the sagittal lattice pores, which are large and occupy fixed positions. Four or five lattice bars are joined to each side of the basal ring; none are present at the position of the primary lateral bars. Spines are not present on the lateral surfaces of the lattice shell, except for rare individuals which bear short lattice spines surrounding incompletely latticed areas.
Goll 1978


Description

 

Images

 

Synonyms

 

References

 

Distribution

 

Discussion / Comments

 

Web links