Cingulochitina PARIS , 1981

Morávek, Radek, 2009, Lower Wenlock Chitinozoa From The Bykoš Locality (Silurian, Prague Basin, Barrandian Area, Czech Republic), Acta Musei Nationalis Pragae Series B 65 (1 - 2), pp. 37-60 : 39-40

Genus Cingulochitina PARIS, 1981

Type species: Desmochitina cingulata EISENACK, 1937

R e m a r k s: The membranous carina is often eroded in the Cingulochitina species. The carina often appears as a folding or thickening.

Cingulochitina angusta VERNIERS, 1999

Pl. 1, figs. 1-7; pl. 7, figs. 1-4.

1981 Linochitina sp. A ; Verniers, pl. 2, fig. 30.

1982 Cingulochitina sp. A ; Verniers, p. 23, pl. 7, figs. 138-142.

cf. 1995 Cingulochitina sp. A ; Dufka, p. 139-141, pl. 1, fig. 10,

11.

1999 Cingulochitina angusta VERNIERS, p. 370-371.

D e s c r i p t i o n: Shape of the vesicle is claviform. Maximal width of the vesicle is above the cingulum. The shoulders and flanks are indistinct. The collarette is flared. The basal edge is rounded and the base is extremely convex. A short cingulum appears on the basal edge. The cingulum is developed as a ridge or as a folding or thickening of the chamber wall. A copula is present. Some of described vesicles are translucent or semitransparent. In this situation a connection between the copula and operculum is then visible. The surface is smooth. Specimens are often found as chains of two, three or more vesicles.

D i s c u s s i o n: Measurements made on Cingulochitina angusta are very similar to the data presented by Verniers (1999) from the Mehaigne area.

In comparision with Cingulochitina sp. A described by

Dufka (1995), C. angusta is shorter and narrower but the overall vesicle shape is very similar.

O c c u r r e n c e: Mehaigne area, Brabant massif, Belgium (Verniers; 1981, 1982, 1999): late Llandovery to early

Wenlock, members MB3D to basal MB4A

Ithon East, Builth Wells district, Wales, UK ( Verniers,

1999): late lower Wenlock (graptolite biozone M. riccartonensis).