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Hystrichogonyaulax canadensis
Hystrichogonyaulax canadensis (Pocock, 1972) Stover and Evitt, 1978
Originally Gonyaulacysta, subsequently Hystrichogonyaulax, thirdly Rhynchodiniopsis.
Tax. jr. synonym of Gonyaulax (as Gonyaulacysta) cladophora Deflandre, 1938, according to Fisher and Riley, 1980.
Jansonius, 1986, retained the species as Rhynchodiniopsis canadensis (Pocock, 1972) Jansonius, 1986, but Kunz, 1990, agreed with Fisher and Riley, 1980.
Holotype: Pocock, 1972, pl.24, fig.1, Jan du Chêne et al., 1986, pl.97, figs.1-4
Locus typicus: Imperial Tidewater Carlyle, Western Canada
Stratum typicum: Oxfordian-Kimmeridgian
Original description: Pocock, 1972, p.89: Gonyaualcysta canadensis
Vesicle more or less isodiametric; epitheca and hypotheca hemispherical; epitheca tapers towards the apex, being terminated by a short apical horn about 10.0 Ám long and 12.0 Ám wide (see diagram); hypotheca smoothly rounded; no antapical processes; transverse furrow helicoidal; strongly developed, longitudinal furrow less well marked; parallel-sided; tabulation 4", 6", 6""", 1""""; archeopyle precingular with a simple free operculum, comprises plate 3", not always developed; sutures reflected onto surface of vesicle as low raised ridges up to 1.0 Ám wide; rows of thin, pinnate spines 2.5 (4.0) 7.7 Ám long and up to 1.0 Ám wide, spaced 2.0 (4.1) 8.8 Ám apart line the crests of the ridges; vesicle two-layered; capsule very thin, smooth; outer layer 1.0-1.5 Ám thick; scabrate; colour pale yellow; length of vesicle 99.0 (104.5) 110.0 Ám; width of vesicle 77.0 (91.4) 106.0 Ám.
Originally Gonyaulacysta, subsequently Hystrichogonyaulax, thirdly Rhynchodiniopsis.
Tax. jr. synonym of Gonyaulax (as Gonyaulacysta) cladophora Deflandre, 1938, according to Fisher and Riley, 1980.
Jansonius, 1986, retained the species as Rhynchodiniopsis canadensis (Pocock, 1972) Jansonius, 1986, but Kunz, 1990, agreed with Fisher and Riley, 1980.
Holotype: Pocock, 1972, pl.24, fig.1, Jan du Chêne et al., 1986, pl.97, figs.1-4
Locus typicus: Imperial Tidewater Carlyle, Western Canada
Stratum typicum: Oxfordian-Kimmeridgian
Original description: Pocock, 1972, p.89: Gonyaualcysta canadensis
Vesicle more or less isodiametric; epitheca and hypotheca hemispherical; epitheca tapers towards the apex, being terminated by a short apical horn about 10.0 Ám long and 12.0 Ám wide (see diagram); hypotheca smoothly rounded; no antapical processes; transverse furrow helicoidal; strongly developed, longitudinal furrow less well marked; parallel-sided; tabulation 4", 6", 6""", 1""""; archeopyle precingular with a simple free operculum, comprises plate 3", not always developed; sutures reflected onto surface of vesicle as low raised ridges up to 1.0 Ám wide; rows of thin, pinnate spines 2.5 (4.0) 7.7 Ám long and up to 1.0 Ám wide, spaced 2.0 (4.1) 8.8 Ám apart line the crests of the ridges; vesicle two-layered; capsule very thin, smooth; outer layer 1.0-1.5 Ám thick; scabrate; colour pale yellow; length of vesicle 99.0 (104.5) 110.0 Ám; width of vesicle 77.0 (91.4) 106.0 Ám.