radiolaria - rads_cenozoic - Lamprocyrtis neoheteroporos

Citation: Lamprocyrtis neoheteroporos Kling 1973

Basionym: Lamprocyrtis neoheteroporos

Synonyms:
1973 Lamprocyrtis neoheteroporos - Kling pl. 5, figs. 17-18
1975 Lamprocyrtis neoheteroporus - Foreman p. 620, pl. 9, fig. 12
1980 Lamprocyrtis neoheteroporus - Sakai p. 711, pl. 9, figs. 9a, 9b
1985 Lamprocyrtis neoheteroporus - Morley pl. 6, fig. 2

Taxonomic discussion: Kling 1973 p.639 pl.5 figs.17-18, pl.15 figs.4-5; Goll 1980 p.436 pl.3 fig.11; Alexandrovich 1989 (ODP 111 SR) pl.2 fig.4

Original description: Two segmented forms with cephalis [three-lobed,] hemispherical to cylindrical, commonly open; with a stout three-bladed apical horn and usually one or more accessory spines; with circular to elliptical, irregularly arranged pores. Collar stricture indistinct. Thorax proximally conical, distally cylindrical to slightly inflated; circular to elliptical or irregular pores, longitudinally aligned, increasing in size distally, becoming two or more times as large along a horizontal discontinuity as in L. heteroporos. Smaller pores may again appear near mouth. Although early specimens show a slight, gentle indentation of the wall at this discontinuity, there is no internal stricture or septal ring separating two segments. Mouth, sometimes slightly constricted, surrounded by irregular row of small teeth; a weak peristome seldom developed. Later specimens become smaller and more inflated.
Remarks on original description: The shell is two-segmented, but shows evidence of its three-segmented ancestor by an abrupt increase in pore size (by a factor of two or more) between the upper and lower parts of the present thorax. The species varies from a compact, small (100 microns in length) form with heavy bars between pores, to a larger form (140 microns in length) with more open lattice and lighter bars. (Sanfilippo et al., 1985)

Description

Biogeography and Palaeobiology

Biostratigraphic distribution

Geological Range:
Last occurrence (top): within Neogene Period (2.59-23.03Ma, top in Piacenzian stage). Data source: Lazarus et al. 2015 - "N age group"
First occurrence (base): within Neogene Period (2.59-23.03Ma, base in Aquitanian stage). Data source: Lazarus et al. 2015 - "N age group"

References:

Alexandrovich, J. M. (1989). Radiolarian biostratigraphy of ODP Leg 111, Site 677, eastern equatorial Pacific, late Miocene through Pleistocene. Proceedings of the Ocean Drilling Program, Scientific Results. 111: 245-262. gs

Foreman, H. P. (1975). Radiolaria from the North Pacific, Deep Sea Drilling Project, Leg 32. Initial Reports of the Deep Sea Drilling Project. 32: 579-676. gs O

Goll, M. R. (1980). Pliocene-Pleistocene radiolarians from the East Pacific Rise and the Galapagos spreading center, Deep Sea Drilling Project Leg 54. Initial Reports of the Deep Sea Drilling Project. 54: 425-453. gs

Kling, S. A. (1973). Radiolaria from the eastern North Pacific, Deep Sea Drilling Project, Leg 18. Initial Reports of the Deep Sea Drilling Project. 18: 617-671. gs

Morley, J. J. (1985). Radiolarians from the northwest Pacific, Deep Sea Drilling Project Leg 86. Initial Reports of the Deep Sea Drilling Project. 86: 399-422. gs

Sakai, T. (1980). Radiolarians from Sites 434, 435 and 436, northwest Pacific, Leg. 56, DSDP. Initial Reports of the Deep Sea Drilling Project. 56-57: 695-733. gs

Lamprocyrtis neoheteroporos

Taxonomy

Description

Biogeography and Palaeobiology

Biostratigraphic distribution

References:

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