Aktasia compacta

(Bukry, 1969) Varol, in prep. Jan 16, 2026

Set number: 2776

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10µm

Aktasia compacta, Late Cenomanian, The specific location cannot be disclosed.

Set number: 2775

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10µm

Aktasia compacta, Middle Cenomanian, The specific location cannot be disclosed.

Set number: 2774

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10µm

Aktasia compacta, Cenomanian, Vergons, SE France

Set number: 2773

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10µm

Aktasia compacta, Early Cenomanian, Vergons, SE France

Set number: 2772

Aktasia compacta, Early Turonian, Angola, West Africa

Set number: 2771

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10µm

Aktasia compacta, Early Turonian, Angola, West Africa

Final Epithet

Aktasia compacta (Bukry, 1969) Varol, in prep.

Basionym

Vagalapilla compacta compacta Bukry, 1969

Synonyms

Helicolithus compactus (Bukry, 1969) Varol & Girgis, 1994

Dimensions Of Holotype

Maximum size: 5.50 µm

Remarks

Small species of Aktasia (< 6.0 µm) have a zeugoid outer wall and a protolith inner wall composed of eight large sub-quadrilateral segments. The central area contains an asymmetrical diagonal cross whose arms are composed of parallel longitudinal segments arranged in two halves and lacking a distal process.

Aktasia compacta is identified from Aktasia irregularis by being smaller than 6.0 µm.

Aktasia compacta differs from Aktasia trabeculatus by having an asymmetrical cross, whereas the latter has a symmetrical cross.

References

Bukry, D. 1969. Upper Cretaceous coccoliths from Texas and Europe. University of Kansas Paleontological Contributions, Articles 51 (Protista 2): 1-79.

Varol, O. & Girgis, M. 1994. New taxa and taxonomy of some Jurassic to Cretaceous calcareous nannofossils. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen. 192: 221-253.

Taxonomy

Aktasia

Biostratigraphy

Stratigraphic Range

Early Cenomanian - Early Maastrichtian

Age (Ma)

100.50? - 69.91?

Holotype

Vagalapilla compacta compacta Bukry, 1969

Early Santonian

Farm Road 1382, South Dallas County, Texas, USA