neptune records: 15
neptune records:
| Daughter taxa (time control age-window is: 0-800Ma) | ||||
| Cassideus mariae neptune records: 15 | |||
| Cassideus sp. neptune records: | ||||
Catalog entries: Cassideus
Original description: Test microgranular, dicyrtid, helmet-shaped about half as high as wide. Cephalis hemispherical with two long primary horns: an apical horn and a vertical horn; horns triradiate in cross-section with three longitudinal grooves, three prominent apical pores present at base of each horn in position of grooves. Series of dendritic ridges (see P1. 25, figs. 3-5, 7, 8) radiate downwards from horns over most of cephalis. Perforations in cephalis small, circular; dispersed irregularly between dendritic ridges. Cephalic skeletal elements rodlike, circular in transverse section; divide cephalis into six colar pores (see P1. 27, fig. 1). Cephalopyle lacking on both the type species and C. yoloensis, n. sp. Thorax proximally quite conical; distally flaring to form broad thoracic skirt. Thoracic wall coarsely perforate; pore frames subhexagonal proximally; becoming hexagonal distally. Thoracic velum not observed though probably present on well-preserved specimens. Cassideus, n. gen., differs from all other Neosciadiocapsidae genera, (1) by possessing two primary horns; an apical horn and a vertical horn and (2) by lacking a cephalopyle.
Published descriptions
Emended description: Theopiliinae with a shell composed of 4-6 segments, the upper part highly conical, the lower part widely enlarged. Presence of a border. Segments separated by septa that are differentiated not only inside the shell, but also on the external surface, constituting characteristic "rings". With a different point of view on the homology of the different parts of the shell, Pessagno has described Cassideus as a two-segmented form. Mostly he ignored the deep internal septa and the velum. With of the base of cephalis nearly 30µm. Ratio of widths and lengths of segment I to III as 1: 1-2: 3-4. By its shape, the shell is close to that of Sethopilium. Pores on the II and III segments small, 4-6µm, distributed with absolutely no order. On the lower part of the third segment, rows of nearly 15-20 pores on the half circumference. Pores very large on the fourth segment. This segment is rapidly enlarging, and looks like a border. A and Vert spines give 2 strong horns, D and L spines do not produce "feet". e definition of the genus has been modified, so that the longitudinal ribs and the ornamentation on the upper part of the shell ("dendritic ridges" of Pessagno) could be plainly used as specific, and not generic, characters. The structure of the cephalis cannot be used as a generic characteristic for other reasons: it is uniform in all representatives of the subfamily. Theopiliinae present other characteristics of a higher rank. This is why it is not excluded that Cassideus could be considered as a subjective synonym of Sethopilium, the main difference between them being precisely the occurrence of a border in Cassideus.
Geological Range:
Last occurrence (top): at top of Paleogene Period (100% up, 23Ma, in Aquitanian stage). Data source: Total of ranges of the species in this database
First occurrence (base): within Paleogene Period (23.03-66.04Ma, base in Danian stage). Data source: Total of ranges of species in this database
Plot of occurrence data:
Pessagno, E. A. Jr. (1969b). The Neosciadiocapsidae, a new family of Upper Cretaceous Radiolaria. Bulletins of American Paleontology. 56(253): 377-439. gsReferences:
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Cassideus compiled by the radiolaria@mikrotax project team viewed: 6-10-2026
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