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Leptodinium saepitum
From Fensome et al., 2019:
Leptodinium saepitum Ashraf, 1979, p.128, pl.2, fig.27; pl.3, figs.1–3,5. Holotype: Ashraf, 1979, pl.3, fig.2. Originally (and now) Leptodinium, subsequently Hystrichogonyaulax, thirdly Rhynchodiniopsis, fourthly Ctenidodinium. Brenner (1988, p.60) retained this species in Leptodinium. Age: Late Jurassic (Malm).
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Original description: [Ashraf, 1979] (translated from German):
Leptodinium saepitum nov. sp.
Pl. 2, Fig. 27, Pl. 3, Figs. 1-3, 5 (Holotype Pl. 3, Fig. 2)
Diagnosis: Fielded integument with a round to polygonal outline. Tall, fence-like suture ridges with serrated to sometimes smooth edges. The left-handed, only slightly spirally ascending transverse furrow is bordered by unequally developed suture ridges, of which the epithecal one is the lower. The inherently unfielded longitudinal furrow is bordered exclusively by very low suture ridges in its epithecal region. Paneling: 3'-4' (apical), 6" (precingular), 5' (postcingular), 1p (intercalary), and 1" (antapical).
The precingulate ardhacopyle is located in field 3".
Holotype: Specimen Karkar Ka 84 27.9 / 92.6. Size: 74 x 63 μm.
Locus typicus: Karkar, northern Afghanistan.
Stratum typicum: Biozone B (Malm).
Derivatio nominis: based on the fence-like suture ridges (Latin saepire = to fence in).
Description: See diagnosis. Size: 74-85 μm x 63-71 μm (with suture ridges). Holotype = 74 x 63 μm, height of suture ridges: 8-12 μm (measured on 12 specimens).
The species-characteristic, fence-like suture ridges are solid up to two-thirds of their height; then they almost always dissolve into processes that widen significantly towards their apex and appear truncated. Occasionally, several processes may fuse together, giving the suture a smooth finish over a short distance.
Remarks: The species Ctenidodinim ornatum (EISENACK 1935) DEFLANDRE 1938 (cf. p. 130 of this work) and Dichadogonyaulax pannea (NORRIS 1965) SARJEANT 1966b (cf. p. 129 of this work), which are considered related, show differences in the paneling pattern and the shape of the sutures (thorny and bifurcate processes on always foveolate suture ridges).
Leptodinium saepitum Ashraf, 1979, p.128, pl.2, fig.27; pl.3, figs.1–3,5. Holotype: Ashraf, 1979, pl.3, fig.2. Originally (and now) Leptodinium, subsequently Hystrichogonyaulax, thirdly Rhynchodiniopsis, fourthly Ctenidodinium. Brenner (1988, p.60) retained this species in Leptodinium. Age: Late Jurassic (Malm).
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Original description: [Ashraf, 1979] (translated from German):
Leptodinium saepitum nov. sp.
Pl. 2, Fig. 27, Pl. 3, Figs. 1-3, 5 (Holotype Pl. 3, Fig. 2)
Diagnosis: Fielded integument with a round to polygonal outline. Tall, fence-like suture ridges with serrated to sometimes smooth edges. The left-handed, only slightly spirally ascending transverse furrow is bordered by unequally developed suture ridges, of which the epithecal one is the lower. The inherently unfielded longitudinal furrow is bordered exclusively by very low suture ridges in its epithecal region. Paneling: 3'-4' (apical), 6" (precingular), 5' (postcingular), 1p (intercalary), and 1" (antapical).
The precingulate ardhacopyle is located in field 3".
Holotype: Specimen Karkar Ka 84 27.9 / 92.6. Size: 74 x 63 μm.
Locus typicus: Karkar, northern Afghanistan.
Stratum typicum: Biozone B (Malm).
Derivatio nominis: based on the fence-like suture ridges (Latin saepire = to fence in).
Description: See diagnosis. Size: 74-85 μm x 63-71 μm (with suture ridges). Holotype = 74 x 63 μm, height of suture ridges: 8-12 μm (measured on 12 specimens).
The species-characteristic, fence-like suture ridges are solid up to two-thirds of their height; then they almost always dissolve into processes that widen significantly towards their apex and appear truncated. Occasionally, several processes may fuse together, giving the suture a smooth finish over a short distance.
Remarks: The species Ctenidodinim ornatum (EISENACK 1935) DEFLANDRE 1938 (cf. p. 130 of this work) and Dichadogonyaulax pannea (NORRIS 1965) SARJEANT 1966b (cf. p. 129 of this work), which are considered related, show differences in the paneling pattern and the shape of the sutures (thorny and bifurcate processes on always foveolate suture ridges).