Taxonomy Online - Carboniferous spores part I - Species details


Species name
Crassispora maculosa (Knox) Sullivan, 1964

Description
Radial, trilete, camerate miospores. Amb circular to subcircular. Trilete mark distinct, sutures straight, extending half to three-quarters of spore radius, accompanied by low relatively narrow, thickened labra, individually up to 4 µm wide, which fuse equatorially into the variably defined equatorial crassitude which is frequently slightly invaginated in the radial positions. Crassitude narrow, weakly developed with ill-defined inner margin. When seen in off-polar compressions, the crassitude simulates curvaturae. Exine up to 3 µm thick, with dense granulate infrastructure. Distal surface of exine ornamented with scattered broad-based coni up to 2–3 µm in height, projecting at equatorial margin. Proximal surface laevigate.

Other descriptions
Knox, 1950, p. 318. Smith and Butterworth, 1967, pp. 235–236, pl. 18, figs. 7–8, pl. 19, fig. 1

Size
Overall equatorial diameter 76(94)120 µm

Remarks
Crassispora kosankei (Potonié & Kremp) Bharadwaj 1957 is smaller, has a wider equatorial crassitude and a more densely distributed conate ornament.

Range
Mississippian; Visean to Serpukhovian [Brigantian to Arnsbergian] (Smith and Butterworth, 1967).

Images

MPK 7074 MPK 7074 Figure 13a
Shales below Faraday House Sill, Argill Beck, Stainmore, Cumbria, England; Serpukhovian [Pendleian], NC Biozone, Sample NC, Specimen MPK 7074. Oblique compression. Note thick exine and narrow equatorial crassitude. Trilete mark distinct, sutures accompanied by elevated folds or ridges, which extend to the crassitude. Distal surface of exine ornamented with relatively coarse conate ornament. Specimen maximum dimension 97 µm.


MPK 7075 MPK 7075 Figure 13b
Shales below Hurlet Limestone, Hurlet Borehole 160.70 m, Scotland; Visean, VF Biozone, Sample MPA 9162, Specimen MPK 7075. Proximal focus of slightly obliquely compressed specimen. Equatorial crassitude, narrow, poorly defined. Exine relatively thick. Proximal surface smooth, distal surface bears fine granular or conate ornament that protrudes at equator. Minor compression fold present. Specimen maximum dimension 90 µm.