- Type images:
 heliasteriscus Clark and Campbell 1942.jpg)
type material: H. heliasteriscus
Catalog entries: Heliodiscus heliasteriscus
 heliasteriscus Clark and Campbell 1942.jpg)
type material: H. heliasteriscusOriginal description: Shell like a sunburst with 10 very short rays wider than long or about the same width as the length, their proximal regions sometimes with a few (two or three) riblets, the rays three-angled in proximal portion, the tips sharp, often curved; cortical shell over five times the diameter of the medullary shell, with small, regular, circular pores, about twenty in a radius or fewer, the pores set into shallow pits with sepaloid points prolonged as. minute spinules, an average of about ten or less in an interradius, cavity of the pores cylindrical, these cavities asymmetrical, directed toward the center of the disc; medullary shell a little greater in diameter than the length of a ray, globular, with few, thick, dense bars and subhexagonal pores set into hexagonal frames; supporting beams obscured by the density of the cortical shell, but thin.
Diameter of cortical shell, 210µm; of medullary shell, 38.6µm; of pores, 8.8µm; length of rays, 29.8µm; width of ray at the base, 32.0µm (at its contact with the disc). Distinguishing characters (rw): A second specimen (Pl. 3, fig. 11) is smaller, but all the spines save one are broken off near the tips. The fine pores are well shown in the specimen.
Heliodiscus heliasteriscus n. sp. has as few rays as the minimum number found in H. pertusus Haeckel (1887), but these rays are shorter, wider, and not fenestrated.
Remarks on original description: [The authors here list this species under the subgeneric name Heliodiscetta and include the subgeneric name in the species name.
Similar species
Geological Range:
Last occurrence (top): within Paleogene Period (23.03-66.04Ma, top in Chattian stage). Data source: Lazarus et al. 2015 - "P age group"
First occurrence (base): within Paleogene Period (23.03-66.04Ma, base in Danian stage). Data source: Lazarus et al. 2015 - "P age group"
Plot of occurrence data:
Clark, B. L. & Campbell, A. S. (1942a). Eocene radiolarian faunas from the Mt. Diablo area, California. Geological Society of America, Special Papers. 39: 1-112. gs Sanfilippo, A. & Riedel, W. R. (1973). Cenozoic Radiolaria (exclusive of theoperids, artostrobiids and amphipyndacids) from the Gulf of Mexico, Deep Sea Drilling Project Leg 10. Initial Reports of the Deep Sea Drilling Project. 10: 475-608. gs OReferences:
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Periphaena heliasteriscus compiled by the radiolaria@mikrotax project team viewed: 2-4-2023
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