Leiostracosia robusta Schrammen 1902 Leiostracosia robusta is a moderately rare species in The Lower Campanian of Höver. It appears to be absent in the Upper Campanian.
Leiostracosia robusta forms narrow funnels with a rough exterior. The thickness of the walls is close to 7 mm in adult individuals. Around the growing margin, the wall thickness deminishes in a wedge-like manner, over a height of about 10 mm
The ostia of Leiostracosia robusta are quite large (3 to 4 mm) and have an irregular outline. They are arranged randomly and are separated by bridges of heavily silica mantled lychnisks. The bridges show numerous tiny (not visible with to the naked eye) circular pores.
At the base, the funnel shows a sharp transition into a short stem with branching roots, consisting of a dense fibrous skeletal meshwork.
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