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Fibrocysta prolixa
Fibrocysta prolixa Harker and Sarjeant in Harker et al., 1990 ex Harker and Sarjeant, 1991
This name was not validly published in Harker et al. (1990), since the lodgement of the holotype was not cited (I.C.N. Article 40.7).
Holotype: Harker et al., 1990, pl.3, fig.15; pl.4, figs.1–2; text-fig.18.
Locus typicus: Gerald, Saskatchewan, Canada
Stratum typicum: Early Campanian
Original diagnosis: Harker, Sarjeant and Caldwell, 1990, p.78
Proximochorate cysts having an ovoidal ambitus and bearing numerous non-tabulate, solid, acuminate processes. Apex prolonged into a long, narrow, tapering horn terminating in a fibrous buccinate process. A small protrusion at the antapex gives rise to a long, solid, acuminate process. Phragma thin (ca. 1 Ám), composed of two closely adpressed layers. Periphragm finely granular (relief less than 1 Ám), giving rise to slender, fibrous, acuminate processes, frequently curved. Paratabulation indistinct; cingulum represented by a double row of processes around the equatorial region. Archaeopyle formed by loss of two precingular paraplates.
Original description: Harker, Sarjeant and Caldwell, 1990, p.78
The apical horn, like the cyst body, has a fine granular ornament. It bears numerous short acuminate processes and terminates in an equally short but thicker process that is fibrous and buccinate (Pl. 4, Fig. 1). The processes are composed of four to six fibres arising from the periphragm. Normally they are isolate; only in the cingular region are they occasionally connected proximally to adjacent processes by low fibrous crests. Their arrangement appears nontabulate. The shape and position of the archaeopyle indicate that it was formed by loss of two precingular paraplates (Pl. 3, Figs. 15, 16, Text-fig. 18).
Dimensions: Holotype: overall length 100 Ám, breadth 54 Ám, length of apical horn 34 Ám, apical process 7 Ám, acuminate processes 7-14 Ám. Range: overall length 86-100 Ám, mean 92 Ám; breadth 43-54 Ám, mean 51 Ám, length of apical horn 20-34 Ám, mean 27 Ám, apical process 5-7 Ám, mean 6 Ám, acuminate processes 7-14 Ám.
Affinities:
Harker, Sarjeant and Caldwell, 1990,, p. 78-79: This species is distinguished from all other species of Fibrocysta by having a long apical horn terminating in a short, fibrous and buccinate process. Fibrocysta lappacea (Drugg 1970) Stover and Evitt 1978, is similar in overall shape but has buccinate, not acuminate, processes on the central body and fibrous apical and antapical horns. F. bipolare (Cookson and Eisenack) Stover and Evitt 1978, differs in having a short, broad, solid apical appendage and a long, unstriated antapical appendage (Cookson and Eisenack 1965b, p. 135). The specimens attributed to that species by Benson (1976, pl. 5, figs. 5-6) are more fusiform than the type material and appear more similar to F. prolixa; they differ in having a much more prominent antapical process.
This name was not validly published in Harker et al. (1990), since the lodgement of the holotype was not cited (I.C.N. Article 40.7).
Holotype: Harker et al., 1990, pl.3, fig.15; pl.4, figs.1–2; text-fig.18.
Locus typicus: Gerald, Saskatchewan, Canada
Stratum typicum: Early Campanian
Original diagnosis: Harker, Sarjeant and Caldwell, 1990, p.78
Proximochorate cysts having an ovoidal ambitus and bearing numerous non-tabulate, solid, acuminate processes. Apex prolonged into a long, narrow, tapering horn terminating in a fibrous buccinate process. A small protrusion at the antapex gives rise to a long, solid, acuminate process. Phragma thin (ca. 1 Ám), composed of two closely adpressed layers. Periphragm finely granular (relief less than 1 Ám), giving rise to slender, fibrous, acuminate processes, frequently curved. Paratabulation indistinct; cingulum represented by a double row of processes around the equatorial region. Archaeopyle formed by loss of two precingular paraplates.
Original description: Harker, Sarjeant and Caldwell, 1990, p.78
The apical horn, like the cyst body, has a fine granular ornament. It bears numerous short acuminate processes and terminates in an equally short but thicker process that is fibrous and buccinate (Pl. 4, Fig. 1). The processes are composed of four to six fibres arising from the periphragm. Normally they are isolate; only in the cingular region are they occasionally connected proximally to adjacent processes by low fibrous crests. Their arrangement appears nontabulate. The shape and position of the archaeopyle indicate that it was formed by loss of two precingular paraplates (Pl. 3, Figs. 15, 16, Text-fig. 18).
Dimensions: Holotype: overall length 100 Ám, breadth 54 Ám, length of apical horn 34 Ám, apical process 7 Ám, acuminate processes 7-14 Ám. Range: overall length 86-100 Ám, mean 92 Ám; breadth 43-54 Ám, mean 51 Ám, length of apical horn 20-34 Ám, mean 27 Ám, apical process 5-7 Ám, mean 6 Ám, acuminate processes 7-14 Ám.
Affinities:
Harker, Sarjeant and Caldwell, 1990,, p. 78-79: This species is distinguished from all other species of Fibrocysta by having a long apical horn terminating in a short, fibrous and buccinate process. Fibrocysta lappacea (Drugg 1970) Stover and Evitt 1978, is similar in overall shape but has buccinate, not acuminate, processes on the central body and fibrous apical and antapical horns. F. bipolare (Cookson and Eisenack) Stover and Evitt 1978, differs in having a short, broad, solid apical appendage and a long, unstriated antapical appendage (Cookson and Eisenack 1965b, p. 135). The specimens attributed to that species by Benson (1976, pl. 5, figs. 5-6) are more fusiform than the type material and appear more similar to F. prolixa; they differ in having a much more prominent antapical process.