radiolaria - rads_cat - Heliodiscus quadratus radiolaria - rads_cat - Heliodiscus quadratus

CATALOG OF ORIGINAL DESCRIPTIONS: Heliodiscus quadratus Clark & Campbell 1942

This page provides data from the catalog of type descriptions. The catalog is sorted alphabetically. Use the current identification link to go back to the main database.

Higher levels: rads_cat -> H -> Heliodiscus -> Heliodiscus quadratus
Other pages this level: << < H. cingillum brevispina, H. echiniscus, H. glyphodon, H. grottensis, H. heliasteriscus, H. hexasteriscus, H. inca, H. lentis, H. linckiaformis, H. marginatus, H. ninae, H. pentasteriscus, H. perplexus, H. pertusus, H. polymorphus, H. quadratus, H. saturnalis, H. saturnalis [junior homonym], H. saturnalis jh, H. siculus, H. solaster, H. sulcatus, H. trigonodon, H. trochiscus, H. tunicatus, H. zoroaster, H. furcatus, H. setosus

Heliodiscus quadratus

Citation: Heliodiscus quadratus Clark & Campbell 1942
taxonomic rank: species
Described on page(s) : p.38
Type specimens: pl.3, fig.16
Type repository: University of California, Museum of Paleontology, San Francisco
Family (traditional): Heliodiscidae
Family (modern): Heliodiscidae

Current identification:

Original Description

Shell like a sunburst with four short rays dividing the shell into practically equal quadrants, short, distinctly three-angled, angles curved, distally decurrent, tips sharp, base very widely expanded with a concave sweep; cortical shell lenticular, strongly biconvex, with small, subcircular pores with thin rims, sunken at the bottom of subhexagonal areas with very short points at the angles of the hexagons, about twenty pores across a diameter, and about twelve in an interradius, cavities of the pores cylindrical, wall thick; medullary shell about 0.3 diameter of the cortical shell with few, large circular pores and wide, dense framework, supporting beams numerous, thin.

Diameter of cortical shell, 180µm; of medullary shell, 52µm; of pores, 8.8µm; length of spines, 43µm; width of wall, 12.2µm; of widest part at base of spine, 32µm.

Extra details from original publication
Distinguishing characters: Heliodiscus quadratus n. sp, differs from the described species of the genus in having but four spines, and these are regularly disposed so as to divide the shell into quarters.

Editors' Notes
[The authors here list this species under the subgeneric name Heliodiscetta and include the subgeneric name in the species name.


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


Heliodiscus quadratus compiled by the radiolaria@mikrotax project team viewed: 19-6-2024

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