rad_org Nephrospyris knutheieri img1642.jpg
rad_org Nephrospyris knutheieri img1643.jpg
rad_org Nephrospyris knutheieri img1642.jpg
rad_org Nephrospyris knutheieri img1643.jpg
1985 Nephrospyris knutheieri - Goll and Bjørklund fig. 6-9
1998 Nephrospyris knutheieri - Bjørklund et al. p. 131 [not figured]
From Suzuki Paleotax db:
1985 Nephrospyris knutheieri n. sp. Goll & Bjørklund p. 115, 117, figs, 6-9
Catalog entries: Nephrospyris knutheieri
type image: N. knutheieri
type image: N. knutheieriOriginal description: Diagnosis: A species of Nephrospyris characterized by a densely trellised cephalis with numerous thread like lattice bars interjoining chaotically disposed lattice spines. Name: In honor of Professor Dr. Knut Heier, Director of the Norwegian Geological Survey, Trondheim, Norway.
Description: Sagittal ring short, about one half total lattice shell height; shape approximates an irregular trapezoid with longest side formed by A M bar (Figs 6D, 8E, 9D), 69 85 µm high, 50 77 µm thick. External longitudinal rib on A M bar (Figs 6C and 8C). Slender A spine 18 27 µm long, trifurcates distally to join apex of lattice shell (Fig. 6C). Small but prominent V spine arises from basal third of V side of sagittal ring in some species (Fig. 6A), but most commonly arises from approximate midpoint of sagittal ring height (Figs 7F, SA, 9D). Micronodular Ax process occurs on M bar at point of juncture with L bars (Figs 6E, 7D E). This structure is represented by an asymmetrical bulbous protrusion in some specimens (Fig. 6F) and in other by a dispersed micronodular field on a smooth ring surface (Fig. 7C). D bar and two L bars are the only basal sagittal ring bars; no sternal bar, secondaryor tertiarylateral bars. Sagittal ring joined directly to Dand Vsides of lattice shell. Three to five single or paired lattice bars are fused to the A M and A V bars of the sagittal ring. One such pair of lattice bars invariably joins the sagittal ring at the base of the Aspine (Fig. 6Q. Lattice bars joined near the midpoints of sagittal ring on both the Dand V sides (Figs 613 C, 8C, 9J) are unpaired on many specimens and result in enlarged sagittal lattice pores (gates according to the terminology of HAECKEL 1887). On other specimens, enlarged sagittal lattice pores are produced by elevation of the attachment points of lattice bars to sagittal ring (Figs 8A, 9C).Basal ring of lattice shell subpolygonal; 87 102 µm wide, 68 92 µm thick; joined directly to Dand V sides of sagittal ring; strongly constricted by sagittal ring and L bars; encloses two pairs of large basal pores (Figs 6E, 7D E, 9M). Major lattice bars 2.5 6.0 µm in diameter arise from basal and sagittal rings and branch chaotically distally to form densely trellised lattice shell. Inflated, D V compressed lattice shell 85 132 µm high, 73 135 µm thick; extends 25 32 µm above apex of sagittal ring without horizontal constriction (Figs 6C D, 913). Numerous small lattice spines arise randomly from the major lattice bars; very fine lattice bars approximately 1.0 µm in diameter arch between these spines to form a loose secondary meshwork (Figs 6B 6D), 9I) that partially covers the sagittal lattice pores of some specimens (Fig. 8B).Incompletely formed specimens have 8 13 short spines projecting from the basal ring (Fig. 7E F). These spines include a D spine and one or two pairs of spines projecting from the juncture with the L bars (Fig. 6G). Other basal lattice spines are randomly distributed. Complete specimens have an imperfectly formed thorax composed of a sparce trellis of lattice bars joined to the basal lattice spines (Fig. 7A B). Composition of thoracic lattice similar to that of cephalis. Thorax 35 56 µm high; terminates in a broad, loosely framed basal aperture. A strong horizontal constriction separates the cephalis and thorax of some specimens (Fig. 8A), but this constriction is not well developed on other specimens (Fig. 6A).
Geological Range:
Last occurrence (top): Extant. Data source: Lazarus et al. 2015 - "R age group"
First occurrence (base): within Quaternary Period (0.00-2.59Ma, base in Gelasian stage). Data source: Lazarus et al. 2015 - "R age group"
Plot of occurrence data:
Bjørklund, K. R., Cortese, G., Swanberg, N. & Schrader, H. J. (1998). Radiolarian faunal provinces in surface sediments of the Greenland, Iceland and Norwegian (GIN) Seas. Marine Micropaleontology. 35(1-2): 105-140. gs Goll, M. R. & Bjørklund, K. R. (1985). Nephrospyris knutheieri sp n., an extant trissocyclid radiolarian (Polycystinea: Nassellarida) from the Norwegian Greenland Sea. Sarsia. 70(2-3): 103-118. gsReferences:
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Nephrospyris knutheieri compiled by the radiolaria@mikrotax project team viewed: 9-9-2024
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