Polystylidium

Fischer, 1965, p. 584

Type Species

Montlivaltia articulata Fromentel and Ferry, 1869, p. 193, pl. 41 fig. 3, pl. 42 fig. 2 a-b; Original Designation

Type Specimen: Lectotype; MNHN R50394; Verified; Dry Preserved

Type Locality: Bathonian of Rumigny (Ardennes; France)

Lectotype and paralectotypes are available. Topotypic specimens cut and figured by Fischer are also available and rich in information.

Description

Solitary trochoid to ceratoid corallum covered by a striated epitheca with strong rolls. Subcircular calice. Radial elements subcompact, attenuated, flexuous septa, often in zigzag, never exsert. In transverse section, septa are often shifted in direction on both sides of pores. Typical anastomosing pattern. Lateral faces ornamented with fine acute granules irregularly distributed. Inner edge swollen. Original columella made of several lamellar elements connected to some inner edges of septa. Long tabuloid dissepiments vertically straightened along the wall and sloping down to the centre.

Remarks

The drawing of lateral faces of septa in Fischer 1965 is highly conceptual and cannot be observed in the type material.

Distribution

• Western Europe; Middle Jurassic

This page has been in preparation since 19-Aug-2009 17:12

This version was contributed by Bernard Lathuilière on 10-Dec-2009 08:11.

Page authors are: Bernard Lathuilière. Please contact the editor if you would like to contribute to the diagnosis of this taxon.

The editor is: Bernard Lathuilière