Taxonomy Online - Carboniferous spores part I - Species details


Species name
Cingulizonates bialatus (Waltz) Smith & Butterworth, 1967

Description
Radial, trilete, cingulate miospores. Amb rounded triangular to subcircular. Trilete mark usually obscure, occasionally distinct, sutures simple, straight, extending to margin of inner body. Intexine thin, laevigate, forming rounded triangular or subcircular inner body, Exoexine extending in the equatorial plane to form bizonate cingulum. Inner zone thicker and wider than outer zone; inner zone overlaps the equatorial margin of the inner body on the distal surface. Outer margin of inner thicker zone bears numerous tubercular processes that project across outer thinner zone. Numerous radially oriented thickened ribs or plications extend across both zones of cingulum. Thinner outer zone of cingulum may be ornamented on its distal surface with small coni less than 1 µm in height.

Other descriptions
Smith and Butterworth, 1967, pp. 260–261, pl. 21, figs. 3–4

Size
Overall equatorial diameter 25(54)77 μm. Diameter of inner body 20(27)35 μm

Remarks
The specimens originally described by Butterworth and Williams as Densosporites striatus were transferred to C. bialatus by Smith and Butterworth (1967). Cingulizonates loricatus (Loose) Butterworth & Smith 1964 is similar but lacks the development of tubercles on the outer margin of the inner thick zone of the cingulum.

Range
Mississippian to Pennsylvanian; Visean to Bashkirian [Duckmantian]; VF to NJ biozones (unpublished information)

Images

MPK 6977 MPK 6977 Figure 5a
Shales below Swinstone House Marine Band, Mousegill Beck, Stainmore, Cumbria, England; Bashkirian [Marsdenian], FR Biozone, Sample T96, Specimen MPK 6977. Proximal focus. Trilete mark simple; sutures extending to equator of subcircular inner body. Cingulum bizonate, darker thicker inner zone wider than thinner outer zone. Outer zone also appears to bear scattered ornament of small coni. Specimen maximum dimension 44 μm.


MPK 6978 MPK 6978 Figure 5b
Shales below Swinstone House Marine Band, Mousegill Beck, Stainmore, Cumbria, England; Bashkirian [Marsdenian], FR Biozone, Sample T96, Specimen MPK 6978. Distal focus showing that the dark inner zone of the cingulum overlaps the equatorial margin of the inner body on the distal surface. Note tubercular outgrowths on the equatorial border of the inner thicker zone of cingulum. Specimen maximum dimension 45 μm.