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Lamprocyclas prionotocodon
Caulet, 1991
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Description - Add description
Lamprocyclas prionotocodon n. sp.
(PI. 3, Figs. 4, 5)
Description. Three-segmented shell, conical to ovate. Cephalis large, ovate, with small subcircular pores. Apical horn stout, oblique, thorny. Vertical spine short, protruding outward as a thorn. Lateral and dorsal spines extending like "shoulders" in the wall of the upper thorax, prolonged into external thorns. Collar stricture distinct. Thorax conical, with longitudinal rows of subcircular pores of nearly the same size. Lumbar stricture not ponounced. Abdomen shorter than thorax. Peristome is a poreless band with a few short indentations.
Remarks. This species is distinguished from other representatives of Lamprocyclas by its stout oblique apical horn, large cephalis and poreless peristome. It is distinguished from L. margatensis by a shorter abdomen. It is probably the ancestor of L. margatensis.
Name. Prionotos (Greek: jagged), kodon (Greek: bell).
Occurrences. The FCO is in upper Oligocene (Sample 119-744A-12H-3, 53-55 cm). Rare specimens occur in the early Miocene at Site 744, but in middle Miocene at DSDP Site 594 (Leg 90). The LCO was not observed.
Dimensions. Length of the cephalic horn: 45-50 μm; of the cephalis: 40-45 μm; of the thorax: 50-55 μm; of the abdomen: 40-45 μm. Maximum breadth of the thorax: 95-100 μm; of the abdomen: 100-110 μm.
Types. Holotype (MNHN no. F61391), Sample 119-744A-12H-3, 53-55 cm, 1-Z21, Oligocene (PL 3, figs. 4-5). Paratype (MNHN no. F61392), Sample 119-744A-11H-6, 53-55 cm, 1-L29, early Miocene.
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