Revised description:Mit den Gattungsmerkmalen . Auf der Innenseite des Ringes sind nur zwei polare Radialstacheln anzutreffen. Sehr kurze Stützstäbe oder winzige Spitzen können an der Innenseite des Äquatorringes auftreten.
[With the characteristics of the genus [not given by the authors]. On the inner side of the ring, only two polar radial spines. Very short strut bars or tiny spikes on the inner side of the equatorial ring.]
Remarks:Die Untergattung Spongosaturnaloides weist vier bis fünf Radialstacheln an der Innenseite des Äquatorringes auf.
[The subgenus Spongosaturnaloides presents four ro five radial beams on the inner side of the equatorial ring.]
Stratigraphic range:Triassic to Cretaceous. Mesozoic.
Subsequent descriptions:YES

New type species:Saturnalis multidentatus Squinabol, 1914 (defined by the specimen figured, 1914, pl.23, fig.11) = (Spongosaturnalis spiniferus Campbell and Clark, 1944b)
Revised description:Ring very narrow with cross section or differentiated (bladed, with swellings or furrows). Outline of ring subcircular, more or less constricted in the attachment regions of the 2 polar spines which are always situated opposite to the interspine spaces on the outer margin of the ring. Whole outer margin of ring with numerous spines. Cortical shells spongy, outer one widely separated from the inner margin of the ring. Medullary shell(s) latticed.
Remarks:In general Acanthocircus Squinabol, 1903b, has quite a different outline of the ring and the spines are mostly restricted to the polar region of the long axis. Also the Acanthocircus species with totally spined ring are mostly quite different by an elongated outline of the ring. Only Acanthocircus italicus (Squinabol, 1914) with suboval outline is similar, but on the other hand this species is rather different from the genus Acanthocircus Squinabol, 1903b, as defined by its type species. Hexasaturnalis n.gen. is distinguished by its hexagonal to octogonal ring outline and the fewer but larger spines. By increase of the spine number the ring outline of Hexasaturnalis n.gen. has changed through polygonal to subcircular. By this Spongosaturnalis Campbell and Clark, 1944b, has seemingly evolved from Hexasaturnalis n.gen.
Stratigraphic range:Middle to Late Cretaceous, Mesozoic.
Subsequent descriptions:YES

Emended description:The shell of all these species [Spongosaturnalis cf. spinifer Campbell and Clark, Spongosaturnalis campbelli Foreman, and Spongosaturnalis multidentatus (Squinabol)] consists of a many-layered spongy shell. At its center there is a heteropolar microsphere similar to that described with the other genera. Its axis may lie in the plane of ring (Pl. 2, fig. 4-7; Pl. 3, fig. 5, 6, 12-14), may be slightly inclined (Pessagno, 1977b, pl. 2, fig. 20) or may be almost normal to the plane of ring... With all Cretaceous species studied there is no axial apical ray, and the four apical rays are practically stemless, the two branches of each ray appearing to arise directly from the basal rays [Br]. Pessagno (1977b) mentioned with A. multidentatus a double medullary shell. However, it is evident that with the spongy-shelled saturnalids a medullary shell cannot be distinguished, each layer being disposed at a relatively equal distance and having a similar structure. Remarks:Spongosaturnalis was defined as having a solid sphere of spongy framework. Later authors either questioned its validity (Pessagno, 1976; Donofrio and Mostler, 1978; De Wever, 1984a) or reconsidered it as an independent genus (Kozur and Mostler, 1983). The problem is not so simple because the shell is not always preserved and the systematics is primary based on the morphology of ring. Stratigraphic range:[No information given] Subsequent descriptions:YES

Literature cited:- Campbell, A. S. and B. L. Clark (1944b). Radiolaria from Upper Cretaceous of Middle California. Geological Society of America Special Paper 57: 1-61.
- De Wever, P. (1984a). Révision des radiolaires mésozoiques de type Saturnalidae, proposition d'une nouvelle classification (Revision of Mesozoic saturnalid-type radiolarians. Proposition of a new classification). Revue de Micropaléontologie 27(1): 10-19.
- Donofrio, D. and H. Mostler (1978). Zur Verbreitung der Saturnalidae (Radiolaria) im Mesozoikum der Nördlichen Kalkalpan und Südalpen. Geologisch Paläontlogische Mitteilungen Innsbruck 7(5): 1-55.
- Dumitrica, P. (1985). Internal morphology of the Saturnalidae (Radiolaria); systematic and phylogenetic consequences. Revue de Micropaléontologie 28(3): 181-196.
- Kozur, H. and H. Mostler (1972). Beiträge zur Erforschung der mesozoischen Radiolarien. Teil I: Revision der Überfamilie Coccodiscacea Haeckel 1862 emend. und Beschreibung ihrer triassischen Vertreter. Geologisch-Paläontologische Mitteilungen Innsbruck 2: 60.
- Kozur, H. and H. Mostler (1983). The polyphyletic origin and the classification of the Mesozoic saturnalids (Radiolaria). Geologisch Ð Paläontologische Mitteilungen Innsbruck 13(1): 1-47.
- Pessagno, E. A. (1976). Radiolarian zonation and stratigraphy of the Upper Cretaceous portion of the Great Valley Sequence, California Coast Ranges. Micropaleontology, Special Publication 2: 1-95.
- Pessagno, E. A. (1977b). Upper Jurassic Radiolaria and radiolarian biostratigraphy of the California Coast Ranges. Micropaleontology 23(1): 56-113.
- Squinabol, S. (1903b). Le Radiolarie dei noduli selciosi nella Scaglia degli Euganei. Contribuzione I. Rivista Italiana di Paleontologia 9: 105-151.
- Squinabol, S. (1914). Contributo alla conoscenza dei Radiolarii fossili del Veneto. Appendice - Di un genera di Radiolari caratteristico del Secondario (Contribution to the knowledge of fossil Radiolaria. Appendix - On a genus of Radiolaria characteristic of the Mesozoic). Memorie dell'Istituto geologico della R. Universita di Padova 2: 249-306.