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Paragonyaulacysta capillosa
Paragonyaulacysta cappilosa (Brideaux and Fisher, 1976) Stover and Evitt, 1978
Originally Pareodinia, subsequently (and now) Paragonyaulacysta.
Holotype: Brideaux and Fisher, 1976, pl.2, figs.5-7
Locus typicus: Elf Hortonwell, District of Franklin, Canada
Stratum typicum: Late Oxfordian-Berriasian
Original diagnosis: Brideaux and Fisher, 1976, p. 20: Pareodinia cappilosa
Periblast with tripartite outline; maximum width at cingulum; prolonged tapering apical horn, subcircular central portion; and moderately prominent antapical prominence (bulge). Periphragm and endophragm closely appressed; periphragm bearing a dense cover of solid, hairlike processes and lineations of processes or faint, low ridges marking outlines of reflected tabulation. Archeopyle intercalary outline often indistinct, formed by loss of two large polygonal reflected intercalary plates; operculum simple, often loosely in place. Reflected tabulation scheme, ?4", 2a, 6", 6c, 5"""-?6""", 1p, 1"""". Cingulum distinct, reflected cingular plates transversely elongate and polygonal; sulcal region rarely distinct, wide anteriorly, narrowing posteriorly; details lacking.
Original description: Brideaux and Fisher, 1976, p. 20: Pareodinia cappilosa
The cyst is elongate, the length generally twice the maximum width, the latter occurring at the latitude of the aingulum. The epitract is distinctly longer than the hypotract; the main portion of the epitract length is formed of the stout, tapering apical horn. The hypotract is prolonged antapically into an antapical prominence, giving the cyst a tripartite outline. The periblast and endoblast are closely appressed. The periphragm is very thin, about 0.5 Ám thick in optical section, and
clearly visible only where gonal parts of the sutures project at the periphery. The endophragm is slightly thicker, about 1.0 Ám thick in optical section. The surface of the periphragm bears a dense cover of slender, tapering hairlike processes, 2-4 Ám but typically 3 Ám long. The processes are more easily seen on the periphery and at the antapices of specimens, but well-preserved specimens confirm a general
process cover. The archeopyle is formed by the loss of two large and polygonal reflected intercalary plates (Type 2I of Evitt, 1967). The outline of the archeopyle is often indistinct. This is especially so when the simple operculum remains in place, and the opening is defined only by the faint principal archeopyle sutures.
Lineate rows of processes or faint low ridges on the periphragm outline a reflected tabulation pattern determined as: ?4", 2a, 6", 6c, 5"""-6""", 1p, 1"""". This tabulation scheme is only partially visible on any given specimen and the scheme is based on a composite study of all material available. Details of the hypotractal and cingular tabulation are generally better preserved than those of the epitract.
The sutures outlining the reflected apical plate series are especially poorly developed but, apparently, there are four reflected apical plates.
The cingulum is variably represented, even on a given specimen. Very faint low ridges, or lineations of processes, outline six reflected cingular plates. The reflected plates are transversely elongate, polygonal and up to 6 Ám in maximum longitudinal dimension. The ventral terminations of the cingulum have been
observed only imperfectly on a few specimens; there is only a slight displacement of these terminations. On such specimens, the sulcal region is faintly visible, but no details of reflected sulcal tabulation are discernible. The sulcus is widest anteriorly and narrows posteriorly. Dimensions - Overall length, 87-135 Ám; maximum overall width, 40-65 Ám.
Affinities:
Brideaux and Fisher, 1976, p. 20: Pareodinia cappilosa
The shape and size of the periblast, the dense cover of hairlike processes and the presence of reflected tabulation distinguish Pareodinia capillosa from other published species assigned to Pareodinia.
Originally Pareodinia, subsequently (and now) Paragonyaulacysta.
Holotype: Brideaux and Fisher, 1976, pl.2, figs.5-7
Locus typicus: Elf Hortonwell, District of Franklin, Canada
Stratum typicum: Late Oxfordian-Berriasian
Original diagnosis: Brideaux and Fisher, 1976, p. 20: Pareodinia cappilosa
Periblast with tripartite outline; maximum width at cingulum; prolonged tapering apical horn, subcircular central portion; and moderately prominent antapical prominence (bulge). Periphragm and endophragm closely appressed; periphragm bearing a dense cover of solid, hairlike processes and lineations of processes or faint, low ridges marking outlines of reflected tabulation. Archeopyle intercalary outline often indistinct, formed by loss of two large polygonal reflected intercalary plates; operculum simple, often loosely in place. Reflected tabulation scheme, ?4", 2a, 6", 6c, 5"""-?6""", 1p, 1"""". Cingulum distinct, reflected cingular plates transversely elongate and polygonal; sulcal region rarely distinct, wide anteriorly, narrowing posteriorly; details lacking.
Original description: Brideaux and Fisher, 1976, p. 20: Pareodinia cappilosa
The cyst is elongate, the length generally twice the maximum width, the latter occurring at the latitude of the aingulum. The epitract is distinctly longer than the hypotract; the main portion of the epitract length is formed of the stout, tapering apical horn. The hypotract is prolonged antapically into an antapical prominence, giving the cyst a tripartite outline. The periblast and endoblast are closely appressed. The periphragm is very thin, about 0.5 Ám thick in optical section, and
clearly visible only where gonal parts of the sutures project at the periphery. The endophragm is slightly thicker, about 1.0 Ám thick in optical section. The surface of the periphragm bears a dense cover of slender, tapering hairlike processes, 2-4 Ám but typically 3 Ám long. The processes are more easily seen on the periphery and at the antapices of specimens, but well-preserved specimens confirm a general
process cover. The archeopyle is formed by the loss of two large and polygonal reflected intercalary plates (Type 2I of Evitt, 1967). The outline of the archeopyle is often indistinct. This is especially so when the simple operculum remains in place, and the opening is defined only by the faint principal archeopyle sutures.
Lineate rows of processes or faint low ridges on the periphragm outline a reflected tabulation pattern determined as: ?4", 2a, 6", 6c, 5"""-6""", 1p, 1"""". This tabulation scheme is only partially visible on any given specimen and the scheme is based on a composite study of all material available. Details of the hypotractal and cingular tabulation are generally better preserved than those of the epitract.
The sutures outlining the reflected apical plate series are especially poorly developed but, apparently, there are four reflected apical plates.
The cingulum is variably represented, even on a given specimen. Very faint low ridges, or lineations of processes, outline six reflected cingular plates. The reflected plates are transversely elongate, polygonal and up to 6 Ám in maximum longitudinal dimension. The ventral terminations of the cingulum have been
observed only imperfectly on a few specimens; there is only a slight displacement of these terminations. On such specimens, the sulcal region is faintly visible, but no details of reflected sulcal tabulation are discernible. The sulcus is widest anteriorly and narrows posteriorly. Dimensions - Overall length, 87-135 Ám; maximum overall width, 40-65 Ám.
Affinities:
Brideaux and Fisher, 1976, p. 20: Pareodinia cappilosa
The shape and size of the periblast, the dense cover of hairlike processes and the presence of reflected tabulation distinguish Pareodinia capillosa from other published species assigned to Pareodinia.