CATALOG OF ORIGINAL DESCRIPTIONS: Sethophormis arachnium Haeckel 1887

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 -> S -> Sethophormis -> Sethophormis arachnium
Other pages this level: S. arachnium, S. asteriscus, S. astrodiscus, S. aurelia, S. cruciata, S. dodecaster, S. enneactis, S. enneastrum, S. eupilium, S. floscula, S. hexagonalis, S. hexalactis, S. leptopilium, S. leptoscenium, S. medusa, S. octalactis, S. pentalactis, S. rotula, S. triloba, S. umbrella

Sethophormis arachnium

Citation: Sethophormis arachnium Haeckel 1887
Rank: species
Type locality: LM19
Type age (chronostrat): [presumably Quaternary though some forms reported from this station appear to be Tertiary]
Type repository: No information given
Described on page(s) : p.1247

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Current identification:

Original Description
Cephalis very large, flat, cap-shaped, trilobed, with hexagonal base, of the same structure as in the three preceding species. The flat discoidal thorax is also similar, and has the same structure as in the preceding species (Pl. 57, fig. 9); but the number of concentric, nine-angled rings is raised from five to eight, and in its outer part nine secondary radial beams are interpolated between the nine primaries, so that the peristome has not nine but eighteen corners.

Size: Cephalis 0.08 diameter, thorax 0.4 diameter.

Editors' Notes
There was no illustration of this species in Haeckel (1887)
Haeckel listed Sethophormis arachnium under the subgeneric name Enneaphormis, but did not include the subgeneric name in the species name.

The \three preceding species\" refers to Sethophormis rotula (pl.57, fig.9), S. triloba and S. enneastrum in Haeckel, 1887a."[comment from RadWorld database]


Haeckel, E (1887). Report on the Radiolaria collected by H.M.S. Challenger during the years 1873-1876. Report on the Scientific Results of the Voyage of H.M.S. Challenger during the year 1873-1876, Zoology. 18: 1-1803. gs


Sethophormis arachnium compiled by the radiolaria@mikrotax project team viewed: 19-4-2021

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