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
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not figuredSethophormis arachnium Haeckel 1887

not figuredSethophormis asteriscus Haeckel 1887

not figuredSethophormis astrodiscus Haeckel 1887

Sethophormis aurelia Haeckel 1887
= Sethophormis aurelia
not figuredSethophormis cruciata Haeckel 1887

Sethophormis dodecaster Haeckel 1887
= Tetraphormis dodecaster
not figuredSethophormis enneactis Haeckel 1887

Sethophormis enneastrum Haeckel 1887

Sethophormis eupilium Haeckel 1887

not figuredSethophormis floscula Haeckel 1887

not figuredSethophormis hexagonalis Haeckel 1887

Sethophormis hexalactis Haeckel 1887

not figuredSethophormis leptopilium Haeckel 1887

not figuredSethophormis leptoscenium Haeckel 1887

not figuredSethophormis medusa Haeckel 1887

not figuredSethophormis octalactis Haeckel 1887

Sethophormis pentalactis Haeckel 1887
= Lampromitra pentalactis
Sethophormis rotula Haeckel 1887

not figuredSethophormis triloba Haeckel 1887

Sethophormis umbrella Haeckel 1887


Citation: Sethophormis Haeckel 1887
Rank: genus
Described on page(s) : 1243
Family (traditional): Plagiacanthidae

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Current identification/main database link: Sethophormis Haeckel 1887

Original Description
Sethophormida (vel Dicyrtida multiradiata aperta) with numerous radial ribs in the wall of the flat and broad, campanulate or nearly discoidal thorax. cephalis also flat and broad, cap-shaped, without horn.

Etymology: From the Greek sethophormis = sieve-basket"

Extra details from original publication
The genus Sethophormis comprises a great number of widely distributed and large Dicyrtida, all agreeing in the flat cap-shaped or nearly discoidal form of the thorax, which has constantly a very delicate network, and is pierced by numerous radial beams. Four of these are commonly primary and direct prolongations of the four cortinar rods in the collar septum, whilst the others are secondary or interpolated ribs. Sethophormis may be derived either from the triradial Lamprodiscus by multiplication of the ribs (or interpolation of secondary ribs between the three primary), or from Halicalyptra by development of transverse rods connecting its terminal feet, and forming a ribbed thorax. Corresponding to the number of the ribs, we may distinguish as subgenera (separate genera in my Prodromus, 1881, p. 432) Tetraphormis with four, Pentaphormis with five, Hexaphormis with six, Octophormis with eight, Enneaphormis with nine, and Astrophormis with ten to twenty or more ribs. The cephalis bears no horn, and is usually large, flat, cap-shaped or hemispherical.

[Junior objective synonym of Tetraphormis Haeckel, 1881a. Although Haeckel here refers to p.432 of his Prodromus of 1881, there is no generic name on that or any other page of that reference related to the name Sethophormis. Therefore, since Sethophormis dates from 1887a and four of the six subgenera names, Tetraphormis, Pentaphormis, Hexaphormis and Enneaphormis date from 1881a, one of the latter four names must be treated as the nominate subgenus and replace Sethophormis.

In the synonymy of, and in the figure description for Sethophormis aurelia Haeckel, 1887a, p.1248, pl.55, figs.3-4, Haeckel introduces the alternative generic name Leptarachnium. The name in the synonymy and on the plate refers only to an unpublished manuscript name, and we thus consider Leptarachnium Haeckel, 1887a to be a junior objective synonym of Sethophormis Haeckel, 1887a. [Foreman and Riedel fiche]
Sub-genera described:


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 compiled by the radiolaria@mikrotax project team viewed: 17-5-2021

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