radiolaria - rads_cat - Phormocyrtis annosa radiolaria - rads_cat - Phormocyrtis annosa

CATALOG OF ORIGINAL DESCRIPTIONS: Phormocyrtis annosa Riedel 1959

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 -> P -> Phormocyrtis -> Phormocyrtis annosa
Other pages this level: P. alexandrae, P. annosa, P. bucharica, P. carinata, P. costata, P. ligulata, P. longicornis, P. proxima, P. quadrata, P. striata, P. striata praexquisita, P. vasculum

Phormocyrtis annosa

Citation: Phormocyrtis annosa Riedel 1959
taxonomic rank: species
Described on page(s) : p.295
Type specimens: pl.2, fig.7
Type repository: Holotype USNM No. 563370, U.S. National Museum, Washington, D.C.
Family (traditional): Pterocorythidae
Family (modern): Pterocorythidae

Current identification/main database link: Theocyrtis annosa (Riedel 1959)

Original Description

Cephalis elongate, lobate, with a few small pores, surmounted by a stout three-bladed horn. Thorax inflated-campanulate, with regular circular pores. Thoracic wall pronouncedly plicate longitudinally, the plicae being separated by three to five longitudinal rows of pores. Abdomen subcylindrical, with a thinner wall than the thorax, and sub-circular to circular pores usually less regularly arranged than in the thorax. In most specimens the thoracic plicae extend into the abdomen, where they become less distinct. Termination of the abdomen usually ragged, but in some specimens with approximately eight to fifteen parallel, triangular lamellar feet or teeth. This species differs from all others of the genus in having a thick-walled, pronouncedly plicate thorax.

(based on thirty specimens): Length of apical horn 68-120µm; of cephalis 30-45µm; of thorax 108-138µm; of abdomen 38-143µm. Maximum breadth (usually at thorax) 130-173µm.

Latin annosus -a -um = old

Extra details from original publication
Distinguishing characters: The structure of the cephalis of Phormocyrtis annosa is apparently similar to that described in Anthocyrtidium cineraria Haeckel and Calocyrtis virginis Haeckel (Riedel, 1957, pp. 84-86 and 90-93).


Riedel, W. R. (1959a). Oligocene and Lower Miocene Radiolaria in tropical Pacific sediments. Micropaleontology. 5(3): 285-302. gs


Phormocyrtis annosa compiled by the radiolaria@mikrotax project team viewed: 17-7-2024

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