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Ynezidinium malloyi

Ynezidinium malloyi Lucas-Clark and Helenes, 2000, p.115,117–118

Holotype: Lucas-Clark and Helenes, 2000, pl.1, figs.1–3, text-fig.4.
Age: late Paleocene.
Type locality: Arroyo El Bulito,Western Santa Ynez Mountains, Santa Barbara County, California, USA.


Original description: Lucas-Clark and Helenes, 2000:
approximately equal length; A smaller than 1µm. Septum between these paraplates completely developed. Paraplates A, B and C extend up the horn for about half of its length and contact paraplate Q. Paraplates lu and B contact P, which caps the horn and accounts for about one-fifth of its length. Porichnion present at triple junction of A/lu/Q. Sixth precingular paraplate (li) is pentagonal and smaller than the other precingulars. Precingular archeopyle reduced. Loss of operculum occurs within the borders of paraplate 4, leaving the parasutural septa intact.
Operculum simple, free.
Cingulum offset by about 1.5 cingular widths. Cingular paraplates completely outlined by ridges or septa. Septa in the posterior sulcal region may be incomplete or weakly developed.
Paraplates partially outlined include ai, Iu, X and Z.

Dimensions:
Holotype central body 40 µm, total with horn, 62 µm.
25 specimens measured: length including crests and horn 50-70 µm; diameter of central body 40-50 µm; horn 625 µm long. Septa 3-12 µm high.

Comparison: Ynezidinium malloyi is easily recognized by its prominent horn, ventral paratabulation pattern, smooth wall, and strongly developed septa and ridges.
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