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Hystrichosphaeropsis downiei
Hystrichosphaeropsis downiei (Pocock, 1972) Stover and Evitt, 1978
Originally Gonyaulacysta, subsequently Hystrichosphaeropsis, thirdly Rhynchodiniopsis?, fourthly Rhynchodiniopsis.
Tax. jr. synonym of Hystrichogonyaulax cladophora (Deflandre, 1938) Stover and Evitt, 1978, according to Fisher and Riley, 1980. This synonymy was accepted by Lentin and Williams, 1981, but was rejected on a later page of the same paper. This inconsistency was corrected in Lentin and Williams, 1985, who accepted the views of Fisher and Riley, 1980, rather than the transfer of this species to Hystrichosphaeropsis by Stover and Evitt, 1978.
Jansonius, 1986, retained the species as Rhynchodiniopsis downiei (Pocock, 1972) Sarjeant, 1982, but Kunz, 1990, agreed with Fisher and Riley, 1980.
Holotype: Pocock, 1972, pl.22, figs.1-2; Jan du Chêne et al., 1986, pl.97, figs.7-12
Locus typicus: Imperial Tidewater Carlyle, W Canada
Stratum typicum: Oxfordian-Kimmeridgian
Original description: Pocock, 1972, p. 87: Gonyaulacysta downiei
Vesicle longer than it is wide; epitheca hemispherical; terminated by a short, blunt process up to 10.0 Ám long and 10.0 Ám wide; hypotheca more elongate; antapex rounded; no processes developed; transverse furrow well developed; helicoidal, longitudinal furrow more or less parallel-sided; tabulation 4", 6", 6""", 1P, 1""""; archeopyle simple, precingular, with simple free operculum; comprises plate 3"; sutures reflected onto surface of vesicle as low raised ridges about 1 Ám wide; bearing rows of pinnate spines 1.5 (3.8) 5.5 Ám long, rising from bases about 1 Ám wide, spaced 2.0-5.0 Ám apart; similar spines flank transverse and longitudinal furrows; vesicle two-layered; capsule thin-walled; smooth, tightly appressed to outer layer; outer layer about 1 Ám thick; granulose; color pale yellow; length of vesicle 91.3-99.0 Ám (excluding spines); equatorial diameter 72.6 (80.0) 88.0 Ám.
Originally Gonyaulacysta, subsequently Hystrichosphaeropsis, thirdly Rhynchodiniopsis?, fourthly Rhynchodiniopsis.
Tax. jr. synonym of Hystrichogonyaulax cladophora (Deflandre, 1938) Stover and Evitt, 1978, according to Fisher and Riley, 1980. This synonymy was accepted by Lentin and Williams, 1981, but was rejected on a later page of the same paper. This inconsistency was corrected in Lentin and Williams, 1985, who accepted the views of Fisher and Riley, 1980, rather than the transfer of this species to Hystrichosphaeropsis by Stover and Evitt, 1978.
Jansonius, 1986, retained the species as Rhynchodiniopsis downiei (Pocock, 1972) Sarjeant, 1982, but Kunz, 1990, agreed with Fisher and Riley, 1980.
Holotype: Pocock, 1972, pl.22, figs.1-2; Jan du Chêne et al., 1986, pl.97, figs.7-12
Locus typicus: Imperial Tidewater Carlyle, W Canada
Stratum typicum: Oxfordian-Kimmeridgian
Original description: Pocock, 1972, p. 87: Gonyaulacysta downiei
Vesicle longer than it is wide; epitheca hemispherical; terminated by a short, blunt process up to 10.0 Ám long and 10.0 Ám wide; hypotheca more elongate; antapex rounded; no processes developed; transverse furrow well developed; helicoidal, longitudinal furrow more or less parallel-sided; tabulation 4", 6", 6""", 1P, 1""""; archeopyle simple, precingular, with simple free operculum; comprises plate 3"; sutures reflected onto surface of vesicle as low raised ridges about 1 Ám wide; bearing rows of pinnate spines 1.5 (3.8) 5.5 Ám long, rising from bases about 1 Ám wide, spaced 2.0-5.0 Ám apart; similar spines flank transverse and longitudinal furrows; vesicle two-layered; capsule thin-walled; smooth, tightly appressed to outer layer; outer layer about 1 Ám thick; granulose; color pale yellow; length of vesicle 91.3-99.0 Ám (excluding spines); equatorial diameter 72.6 (80.0) 88.0 Ám.