Nannotax Enabling nannofossil research

Description: Umbilocosphaera coccoliths with wide central-area and narrow rim. Shields of similar size. The distal shield is slightly domed and is formed of shallowly imbricated elements, giving a complex suture pattern. The proximal shield consists of a single cycle of non-imbricated elements with nearly radial sutures, it is nearly flat except for a collar on its lower surface. A well developed tube separates the shields.

Remarks: Often placed in Geminilithella.

Original description:

LMs
SEMs - proximal
SEMs - distal

Synonymy

:

• Cyclococcolithus rotula Kamptner 1956 p.10, ex Kamptner 1948 p.8, pl.2/15; Muller 1974a p.591, pl.3/6-8; Muller 1974b p.391, pl.1/7-8; Jafar 1975a p.72 pl.8/2,18-19 (?pl.2/20-23).
• Cyclococcolithus aequiscutum Gartner 1967b p.4, pl.7/1-4.
• Cyclococcolithus cricotus Gartner 1967b partim pl.7/7, non pl.7/5-6. (=Pseudoemiliania lacunosa).
• Calcidiscus aequiscutum (Gartner) Loeblich & Tappan 1978 p.1391; Steinmetz & Stradner 1984 partim, pl.24/3-6 non pl.24/1-2 (=Coronocyclus nitescens).
• Cyclolithella rotula (Kamptner) Haq & Berggren 1978 p.1192, pl.1/15-16.
• Geminilithella rotula (Kamptner) Backman 1980 p.52, pl.1/14-15, 8/3; Theodoridis pl.3/1-2.
• Umbilicosphaera lordii Varol 1982 p.248, pl.4/5