CATALOG OF ORIGINAL DESCRIPTIONS: Lithatractus pierinae 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 -> L -> Lithatractus -> Lithatractus pierinae
Other pages this level: L. birostratus, L. carduelis, L. cirsium, L. conifer, L. conostylus, L. convallaria, L. echiniscus, L. floridus, L. fragilis, L. gamoporus, L. hederae, L. hexagonalis, L. jugatus, L. leptostylus, L. lobatus, L. miocaenica, L. nucleolus, L. nuphar, L. pachystylus, L. pierinae, L. pterosphaerus, L. rosetta, L. santaeannae, L. santaeannae pusillus, L. timmsi, L. timmsi quadrispinus

Lithatractus pierinae

Citation: Lithatractus pierinae Clark & Campbell 1942
Rank: species
Type specimens: pl.5, fig.25
Type repository: University of California, Museum of Paleontology, San Francisco
Described on page(s) : p.34
Family (traditional): Actinommidae
Family (modern): Saturnalidae

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Current identification/main database link: Axoprunum pierinae (Clark and Campbell 1942)

Original Description
Shell ovate, with two opposite thick equal polar spines, about 0.67 of the length of the cortical shell, round in cross section, with the ringlet nud hooklets. near 0.33 of the length of the spine from the base, base not expanded, tip bluntly sharpened; cortical shell dense, brownish, its width 89% of its length, surface nearly smooth, wall with about fourteen pores across the equator and eighteen from pole to pole, these pores subcircular, unequal in size, with very thin rims, wall thick, with extremely short subsepaloid projections bounding the faint subhexagonal areas from whose centers the pores arise; medullary shell only slightly longer than wide, about 42% of the long axis of the cortical shell in diameter, its wall very thin, with faint subhexagonal pores and thin bars, supporting beams. six, arranged in two nearly equatorial pairs, and two strong polar ones.

Length of polar spines, 120µm; dimensions of cortical shell, 160 and 180µm respectively for the two axes; of the medullary shell, 43 and 46µm respectively for the two axes; width of spine 21µm; of wall, 16.6µm; diameter of pores, 6.6-8.0µm. Distinguishing characters (rw): Lithatractus pierinae n. sp. has larger pores than either L. conifer Haeckel (1887) or L. jugatus Haeckel (1887). It differs from the common Barbados, and recent L. lobatus Haeckel (1887) in not having lobulate or dentate pores. The latter species appear to be always lobulate, although in other characters, L. pierinae n. sp. might be considered a mere variant.

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


Clark, B. L. & Campbell, A. S. (1942). Eocene radiolarian faunas from the Mt. Diablo area, California. Geological Society of America, Special Papers. 39: 1-112. gs


Lithatractus pierinae compiled by the radiolaria@mikrotax project team viewed: 20-4-2021

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