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Escharisphaeridia rudis
Escharisphaeridia rudis Davies, 1983; emend. Prauss, 1989
Holotype: Davies, 1983, pl.10, fig.13
Locus typicus: Ellef Ringnes Island, District of Franklin, Northwest Territories, Canada
Stratum typicum: Late Callovian-Valanginian
Translation Prauss, 1989: LPP
Original diagnosis: Davies, 1983, p. 28
A species of Escharisphaeridia with a spherical to subspherical shape; thick wall; densely granulate ornament with a few large, scattered, irregular shaped tubercules. Tabulation: as revealed by archeopyle sutures, 4", 6". Archeopyle: (4A) with operculum occasionally hinged ventrally.
Size: length 49(65)92 µm; breadth 44(66)90 µm.
Original description: Davies, 1983, p. 28
The autophragm is thick (1.5-2.5 µm). The granulate ornament has considerable variability from verrucate, rugulate, alveolate to imperfectly reticulate as the individual tubercules (1-3 µm in diameter) coalesce. Attempts to separate these variants into different taxa proved impossible due to the intergradation. An inward thickening, the omphalos, at the midventral area is usually present. The archeopyle often has accessory sutures between the precingular plates. No other tabulation is evident.
Emended description: Prauss, 1989, p.34
Cyst proximate/acavate. Outline sphaeroidal to ovoidal. Wall composed of pedium and luxuria, thickwalled. Pedium thin, solid. Luxuria thick, often with fibrous, clavate elements which cover the cyst densely or are sponge-like developed.
Further, microreticulate, rugulate and granulate ornamentation is possible. Sulcal area usually free of ornamentation. Apical area (finis of area 1"/4") luxuriate elements produced into a small horn. Areation and cingulum marked by finate reductions of the luxuria. Areation: ?PR, 4", 6"", Xc, NRs. Hypocyst npnareate. Accessory archaeopyle sutures are indicates.
Dimensions: (diameter, range) 41.3 µm, wall (range) 3.4 µm.
Affinities:
Davies, 1983, p. 28: Sentusidinium cuculliformis, S. echinatum, S. pilosum, S. rioultii, and S. villerense are distinguished from E. rudis by their possession of spinate processes. ?Canningia rotundata is distinguished by its vermiculate ornament and short apical horn. ?Canningia circularia is distinguished from E. rudis by its sharply terminating, less dense apiculate elements. Canningia ringnesiorium is distinguished by its less dense ornament and thinner autophragm. E. pocockii has finer, less dense ornament with a smaller size range (length 38-45 µm, breadth 50-55 µm) and a thinner autophragm.
Holotype: Davies, 1983, pl.10, fig.13
Locus typicus: Ellef Ringnes Island, District of Franklin, Northwest Territories, Canada
Stratum typicum: Late Callovian-Valanginian
Translation Prauss, 1989: LPP
Original diagnosis: Davies, 1983, p. 28
A species of Escharisphaeridia with a spherical to subspherical shape; thick wall; densely granulate ornament with a few large, scattered, irregular shaped tubercules. Tabulation: as revealed by archeopyle sutures, 4", 6". Archeopyle: (4A) with operculum occasionally hinged ventrally.
Size: length 49(65)92 µm; breadth 44(66)90 µm.
Original description: Davies, 1983, p. 28
The autophragm is thick (1.5-2.5 µm). The granulate ornament has considerable variability from verrucate, rugulate, alveolate to imperfectly reticulate as the individual tubercules (1-3 µm in diameter) coalesce. Attempts to separate these variants into different taxa proved impossible due to the intergradation. An inward thickening, the omphalos, at the midventral area is usually present. The archeopyle often has accessory sutures between the precingular plates. No other tabulation is evident.
Emended description: Prauss, 1989, p.34
Cyst proximate/acavate. Outline sphaeroidal to ovoidal. Wall composed of pedium and luxuria, thickwalled. Pedium thin, solid. Luxuria thick, often with fibrous, clavate elements which cover the cyst densely or are sponge-like developed.
Further, microreticulate, rugulate and granulate ornamentation is possible. Sulcal area usually free of ornamentation. Apical area (finis of area 1"/4") luxuriate elements produced into a small horn. Areation and cingulum marked by finate reductions of the luxuria. Areation: ?PR, 4", 6"", Xc, NRs. Hypocyst npnareate. Accessory archaeopyle sutures are indicates.
Dimensions: (diameter, range) 41.3 µm, wall (range) 3.4 µm.
Affinities:
Davies, 1983, p. 28: Sentusidinium cuculliformis, S. echinatum, S. pilosum, S. rioultii, and S. villerense are distinguished from E. rudis by their possession of spinate processes. ?Canningia rotundata is distinguished by its vermiculate ornament and short apical horn. ?Canningia circularia is distinguished from E. rudis by its sharply terminating, less dense apiculate elements. Canningia ringnesiorium is distinguished by its less dense ornament and thinner autophragm. E. pocockii has finer, less dense ornament with a smaller size range (length 38-45 µm, breadth 50-55 µm) and a thinner autophragm.