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Spiniferites aliger
Spiniferites aligerus Singh, 1983
This epithet, meaning winged, is correctly rendered as aliger when masculine, aligera when feminine and algerum when neuter.
Holotype: Singh, 1983, pl.50, fig.1
Locus typicus: Peace River area, Canada
Stratum typicum: Early Cenomanian
Original description: Singh, 1983, p. 143
Chorate cysts; central body prolate, ellipsoidal, bearing up to 25 µm high parasutural crests and projections; antapical parasutural crests highest, forming a strong dorsal and lateral flange around paraplate 1""""; antapical flange wide, rectangular with a straight antapical margin, and oriented parallel to the long axis of the central body; length of the antapical flange ranging from 1/3 to 1/2 of the length of the central body; parasutural crests higher at the paraplate corners in the cingular and apical regions, forming broad-based, conical projections, high, flat, membranous crests, and rarely isolated, acuminate projections; conical projections bifid with broad extremities bearing minute spinules; membranous crests and antapical flange supported by narrow linear thickenings usually protruding as 2- to 3 µm long spinules above the crests; periphragm coarsely granulate; paratabulation not clearly discernible, probably gonyaulacacean; paracingulum helicoidal; ventral ends of the paracingulum offset by about two cingular widths; archeopyle precingular, type P 13" only); operculum free, often remaining in place or slightly displaced.
Size range: Overall length including the crests 72(80)89 µm. Holotype 79 µm. Overall breadth including the crests 60(67)72 µm. Holotype 64 µm. Length of the central body 47(53)60 µm. Holotype 51 µm. Breadth of the central body 39(46)53 µm. Holotype 42 µm.
Length of the antapical flange 16(21)25 µm. Holotype 24 µm. Breadth of the antapical flange 26(34)41 µm. Holotype 33 µm. Length of the remaining projections 10(12)15 µm. Holotype 10 to 12 µm. Specimens measured 20.
Affinities:
Singh, 1983, p. 143: Spiniferites aligerus is characterized by a very large antapical flange, high parasutural crests and projections concentrated in the apical and cingular regions. The pre- and postcingular regions of the central body are usually devoid of high parasutural crests. It lacks distinct trifurcate (gonal) and bifurcate (intergonal) processes, which are replaced by high parasutural crests and projections at the corners of the paraplates. In this respect, S. aligerus belongs to the same morphological group as some species of the genus Spiniferites which either lack processes or have processes with exceptionally short stalks not protruding much above the parasutural crests e.g. Spiniferites cingulatus (O. Wetzel) Sarjeant, 1970.
Spiniferites wetzelii (Deflandre) Sarjeant, 1970, resembles S. aligerus in possessing a large antapical flange, but differs in having trifurcate (gonal) and bifurcate (intergonal) processes, which protrude much above the parasutural crests on the central body (see Kjellstrom, 1973, p. 47, fig. 39).
This epithet, meaning winged, is correctly rendered as aliger when masculine, aligera when feminine and algerum when neuter.
Holotype: Singh, 1983, pl.50, fig.1
Locus typicus: Peace River area, Canada
Stratum typicum: Early Cenomanian
Original description: Singh, 1983, p. 143
Chorate cysts; central body prolate, ellipsoidal, bearing up to 25 µm high parasutural crests and projections; antapical parasutural crests highest, forming a strong dorsal and lateral flange around paraplate 1""""; antapical flange wide, rectangular with a straight antapical margin, and oriented parallel to the long axis of the central body; length of the antapical flange ranging from 1/3 to 1/2 of the length of the central body; parasutural crests higher at the paraplate corners in the cingular and apical regions, forming broad-based, conical projections, high, flat, membranous crests, and rarely isolated, acuminate projections; conical projections bifid with broad extremities bearing minute spinules; membranous crests and antapical flange supported by narrow linear thickenings usually protruding as 2- to 3 µm long spinules above the crests; periphragm coarsely granulate; paratabulation not clearly discernible, probably gonyaulacacean; paracingulum helicoidal; ventral ends of the paracingulum offset by about two cingular widths; archeopyle precingular, type P 13" only); operculum free, often remaining in place or slightly displaced.
Size range: Overall length including the crests 72(80)89 µm. Holotype 79 µm. Overall breadth including the crests 60(67)72 µm. Holotype 64 µm. Length of the central body 47(53)60 µm. Holotype 51 µm. Breadth of the central body 39(46)53 µm. Holotype 42 µm.
Length of the antapical flange 16(21)25 µm. Holotype 24 µm. Breadth of the antapical flange 26(34)41 µm. Holotype 33 µm. Length of the remaining projections 10(12)15 µm. Holotype 10 to 12 µm. Specimens measured 20.
Affinities:
Singh, 1983, p. 143: Spiniferites aligerus is characterized by a very large antapical flange, high parasutural crests and projections concentrated in the apical and cingular regions. The pre- and postcingular regions of the central body are usually devoid of high parasutural crests. It lacks distinct trifurcate (gonal) and bifurcate (intergonal) processes, which are replaced by high parasutural crests and projections at the corners of the paraplates. In this respect, S. aligerus belongs to the same morphological group as some species of the genus Spiniferites which either lack processes or have processes with exceptionally short stalks not protruding much above the parasutural crests e.g. Spiniferites cingulatus (O. Wetzel) Sarjeant, 1970.
Spiniferites wetzelii (Deflandre) Sarjeant, 1970, resembles S. aligerus in possessing a large antapical flange, but differs in having trifurcate (gonal) and bifurcate (intergonal) processes, which protrude much above the parasutural crests on the central body (see Kjellstrom, 1973, p. 47, fig. 39).