Aktasia compacta

Vagalapilla compacta compacta Bukry, 1969

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

Maximum size: 5.50 µm

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.

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.