Back
Susadinium scrofoides ssp. scrofoides

Susadinium scrofoides ssp. scrofoides

Autonym.
Below, 1987 emended the diagnosis of this taxon, as Dodekovia scrofoides var. scrofoides.
Holotype: Dörhöfer and Davies, 1980, fig. 24I
Locus typicus: Savik Formation, Reindeer Peninsula, Ellef Ringnes Island, Sverdrup Basin, Arctic Canada
Stratum typicum: Toarcian, Bathonian

Original description: Dörhöfer and Davies, 1980, p. 28-29: Susadinium scrofoides
Diagnosis: A species of Susadinium with a short apical horn and rounded to angular intratabular protuberances in the pre- and postcingular plate series. Autophragm thin, smooth to granulate. Cingulum and sulcus broad. Tabulation 4", 5a, 6"", ?6c, 5""", ?1"""". Archeopyle 3I(plates 2-4).

Remarks: Autoblast often dorsoventrally compressed. The precingular series consists of five short rounded protuberances, the postcingular of three short dorsal and two larger bulging ventral protuberances flanking the sulcus. The apical horn is often sharply pointed with an apical angle of 35-40 degrees. Sutural granules sometimes delimit the apical plates and ventral cingular plates. The tabulation formula was obtained from plate sutures and intratabular protuberances.
The broad sulcal area might include additional plates of the pre- and postcingular series, which are not provided with intratabular protuberances. Cantulodinium protuberatum Wall, 1965 superficially resembles S. scrofoides, but due to its inadequate description and illustration closer comparisons are not possible. Length 29(38)42 µm; width 19(22)26 µm.


Supplemental description: Below, 1987, p.120 as emended description for Dodekovia scrofoides var. scrofoides
Arrangement of vesicles/plates on the dinoflagellate amphiesma cop, pop, cap, 5", 3a, 7""-6", 7c, 5""", 2"""", as, y, z, ps; 1"""" and 2"""" located symmetrically on either side of the dorsoventral plane.
Cyst form proximate, acavate-apiculocavate, oblong ovaloidal, apically also conical to tentoriate, with a broad cingular constriction and rounded areate protuberances; protuberances reflecting 1""" and 2""" and 4""" and 5""" fused basally or completely into large, broad, dextro- or sinistrolateral evaginations, cyst oval to circular in equatorial cross-section; size small; wall composed of pedium and luxuria; surface smooth, scabrate or granular, protuberances distally unornamented, very coarsely shagreen or with low baculi, ornament peniareate along the margins of protuberances or also intraareate, so that the outlines of the homologous plates are not reflected, or schematically reflected, or exactly reflected; areation extensively reflected by protuberances and their ornamentation, NR PR/XPR/cop, pop, cap, NR"/NR1", X2", X3", X4", X5", NRa/X1a, 2a[arch], X3a, X1", X2", X3", X4", X5", X6", X7", NRc, X1""", X2""", X3""", X4""", X5""", X1"""", X2"""", NRs; PR an undifferentiated cusp or nodular cop surrounded by annular pop, apical plates mirrored by a field of ornament around the apex which is undifferentiated, always interrupted only ventrally or divided into 2", 3", 4", and 5", 1" not reflected; 3 anterior intercalaries not marked by protuberances and seldom marked by ornament, usually only an undifferentiated, glabrous sector; fastigiate or heptagonal shape of 2a determined by archeopyle; 6-7 precingulars reflected by large protuberances circular or polyhedral in cross section; cingulum a planar or weakly laevorotatory, broad indentation without protuberances; of the 5 postcingular protuberances, the laterals are largely fused, large 1"""" (L) usually reduced, fused with 1""" and 2""" as a low protuberance or plane, ornamented or without ornaments, large 2"""" a protuberance displaced towards RL; sulcus undivided, lightly indented; archeopyle anterior intercalary, 2a, with monoareate, secate operculum, opercular formula 2a[s].
Size: Holotype: length 38 µm.
Feedback/Report bug