Gonyaulacysta? kleithria DUXBURY 1983

Paratype
Pl. 5, fig(s). 1, 2
NHM registration number: FD62(1)
 

Transmitted light images:

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Dorsal face in high focus
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Optical section
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Ventral face in low focus
 

Original diagnosis:

"A fairly large, partially cavate, gonyaulacacean dinoflagellate cyst species. The smooth endocyst is approximately square in outline and has a distinct, distally rounded and closed apical projection. The pericyst, which is also smooth, is in contact with the endocyst only on the dorsal surface and is produced into a well-developed, straight or concave-sided, open apical horn. Paratabulation of the formula 4', la.s., 6”, ?c, 5''', 1p., 1p.v., 1'''' is marked on the pericoel surface by low crests which are distally irregularly denticulate. An irregular hole is observed in the ventral pericoel, presumably marking the parasulcus. An archeopyle is formed by detachment of paraplate 3''." - From Duxbury (1983, p. 47).