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Lychnocanoma parallelipes Motoyama, 1996

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Lychnocanoma parallelipes Motoyama n. sp.
Plate 5, figures 12a, 12b; 13, 14

Holotype: MPC-4963; DSDP Site 302, Core 14, CC , slide 1, (EF) O44/4. Plate 15, figures 2a, 2b.

Description: Cephalis moderate in size, semi globular in outline with a long apical horn. Apical horn, simple, unbladed, and its length being 1.5 times to twice as long as cephalic diameter. In most specimens numerous short spines arise on the cephalis. Collar stricture indistinct because o f heavy silicification accompanied
by numerous short spines. Thorax conical, thick, hexagonally framed. In many specimens, outline of upper thorax fairly flat. Thoracic pores, medium and regular in size, arranged in a quincuncial-longitudinal row. About 9-12 pores on a half circumference. In many specimens, pore bars being equipped with numerous short spines. Thorax termination being a thickened rim. Three feel, arising from terminal thorax, three-bladed, parallel, vertical, straight or slightly curved with outward
convexity. The dislance between distal pinpoints of two feel usually shorter than the width of thorax.

Measurements: based on ten specimens, length of apical horn: 30-70µm; cephalic diameter: 30-48µm; length of thorax: 85-100µm; width of thorax: 100-I30µm; length of foot: 100-I30µm; distance between pinpoints of two feet: 70-l20µm.

Distinguishing characters: Lychnocanoma parallelipes is closely related to L. magnacornuta, and possibly evolved from L. magnacornuta. Lychnocanoma parallelipes differs from L. magnacornuta by its parallel or slightly convergent feet. Many specimens of L. parallelipes are also marked with numerous thorns on cephalis and upper thorax.

Occurrence: This species is restricted to the late Miocene to earliest Plioeene interval, and has been found in the northwestern North Pacific.

Derivation of name: From the Latin "parallelus", meaning parallel, and "pes", meaning foot.
Motoyama 1996











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