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Omatia alaskaensis
Omatia alaskaensis "alaskaensis" Stover and Evitt, 1978, p.178. Holotype: Wiggins, 1969, pl.1, figs.1–3 (as Herendeenia pisciformis). NOW Herendeenia. Originally Omatia, subsequently (and now) Herendeenia. Age: Neocomian, ?late Hauterivian–Barremian.
Original description (Stover and Evitt, 1978)
= Herendeenia pisciformis of Wiggins, 1969
Description of Herendeenia pisciformis of Wiggins, 1969: Revised diagnosis: Wiggins 1969, p. 146, 148: Herendeenia pisciformis. Same as the genus (Herendeenia) with the following additional remarks. The tabulation is indistinct oronly partially discernible unless the sutures are accompanied by the finlike membrane. The difficulty in delineating this pattern increases with coarser theca ornamentation. The operculum is normally discarded, but in rare instances it can be found in place within the archeopyle, or collapsed into the central cyst. The finlike membrane surrounds the margins of the 1', 2', 3', and 1'"' plates, and extends partially along the precingular, postcingular, and posterior intercalary plate margins. Eight prominent peaks are formed by membrane juncture in the apical region, and six less prominent ones are similarly formed in the antapical region. The theca and finlike membrane surfaces are granulose, with a variable degree of coarseness.
Dimensions. Hypotype, over-all length 96 microns, width 35 microns. Over-all length 56-116 microns, width 18-40 microns, on 150 specimens measured. The average over-all length was 86 microns, and the average over-all width was 30 microns
Age and occurrence. Neocomian, probably late Hauterivian to Barremian, of unnamed Lower Cretaceous stratigraphic unit, Kamishak Hills, Alaska Peninsula, and of Herendeen Limestone, Herendeen Bay, Alaska Peninsula. Upper Jurassic of Omati, Papua, New Guinea.
Comments. The holotype is larger than any of the measured specimens from Alaska. However, size is a highly variable characteristic in this species.
Original description (Stover and Evitt, 1978)
= Herendeenia pisciformis of Wiggins, 1969
Description of Herendeenia pisciformis of Wiggins, 1969: Revised diagnosis: Wiggins 1969, p. 146, 148: Herendeenia pisciformis. Same as the genus (Herendeenia) with the following additional remarks. The tabulation is indistinct oronly partially discernible unless the sutures are accompanied by the finlike membrane. The difficulty in delineating this pattern increases with coarser theca ornamentation. The operculum is normally discarded, but in rare instances it can be found in place within the archeopyle, or collapsed into the central cyst. The finlike membrane surrounds the margins of the 1', 2', 3', and 1'"' plates, and extends partially along the precingular, postcingular, and posterior intercalary plate margins. Eight prominent peaks are formed by membrane juncture in the apical region, and six less prominent ones are similarly formed in the antapical region. The theca and finlike membrane surfaces are granulose, with a variable degree of coarseness.
Dimensions. Hypotype, over-all length 96 microns, width 35 microns. Over-all length 56-116 microns, width 18-40 microns, on 150 specimens measured. The average over-all length was 86 microns, and the average over-all width was 30 microns
Age and occurrence. Neocomian, probably late Hauterivian to Barremian, of unnamed Lower Cretaceous stratigraphic unit, Kamishak Hills, Alaska Peninsula, and of Herendeen Limestone, Herendeen Bay, Alaska Peninsula. Upper Jurassic of Omati, Papua, New Guinea.
Comments. The holotype is larger than any of the measured specimens from Alaska. However, size is a highly variable characteristic in this species.