Taxonomy Online - Carboniferous spores part I - Species details


Species name
Spinozonotriletes uncatus Hacquebard, 1957

Description
Radial, trilete, camerate miospores. Amb convexly rounded triangular. Trilete mark distinct, sutures straight though often obscured; extend to margin of inner body, accompanied by elevated flexuous folds of exoexine which extend decreasing in height, to the equatorial margin. Intexine thin, forms inner body, which is conformable in outline with the amb of the spore and occupies approximately three-quarters of the total spore diameter. Exoexine 3–6 µm thick, extended in the equatorial plane to form solid flange. Exoexine prominently ornamented with large spini which are concentrated in the equatorial region, commonly reduced in the distal polar region and completely absent from contact areas of proximal surface. Spini have broad, often bulbous bases and sharply pointed terminations; height 4–19 µm and basal diameter 2–6 µm. Spina size variable between specimens but uniform on any one specimen.

Other descriptions
Hacquebard, 1957, p. 316, pl. 3, figs. 8–10. Playford, 1962, p. 657, pl. 94, figs. 4–6. Neves and Owens, 1966, pp. 355–356, pl. 3, figs. 2–3

Size
Overall equatorial diameter excluding projecting ornament 74(104)150 µm

Remarks
Spinozonotriletes conspicuus Playford 1964, and S. tenuispinosus Hacquebard 1957, are both similar but lack the elevated, flexuous, sutural folds present in S. uncatus.

Range
Devonian to Mississippian; Tournaisian; LL to CM biozones (Higgs et al., 1988)

Images

MPK 7449 MPK 7449 Figure 56a
Pinskey Gill Beds, Wygarth Gill Borehole, Ravenstonedale, Cumbria, England; Tournaisian, CM Biozone, Sample MPA 298, Specimen MPK 7449. Proximal focus. Rounded triangular zonate miospore with convex sides and roundly pointed apices. Inner body subcircular. Exoexine extended equatorially to form undifferentiated flange. Entire distal and equatorial portions of proximal surface of exoexine ornamented with stout bulbous-based spinae. Elements sharply pointed and commonly curved. Elements more or less evenly distributed. Specimen maximum dimension 114 µm.


MPK 7450 MPK 7450 Figure 56b
Pinskey Gill Beds, Wygarth Gill Borehole, Ravenstonedale, Cumbria, England; Tournaisian, CM Biozone, Sample MPA 302, Specimen MPK 7450. Proximal surface flattened, distal surface hemispherical. Note proximal apical structure formed by exoexinal folds accompanying trilete sutures. Spinose ornament more or less evenly distributed over entire distal surface. Specimen maximum dimension 120 µm.