Gonyaulax jurassica Deflandre, 1938

Now Gonyaulacysta. Originally Gonyaulax, subsequently (and now) Gonyaulacysta.
axonomic junior synonym: Psaligonyaulax (as Gonyaulacysta) dualis, according to Sarjeant (1982b, p.29) - however, Jan du Chêne et al. (1986a, p.131) retained Gonyaulacysta dualis

Holotype: Deflandre, 1938, pl.6, figs.2-3, text-figs.1-2; Jan du Chêne et al., 1986, pl.37, figs.1-3
Age: Oxfordian