Main Content

The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Ref ID : 7499

Benjamin M. Waggoner; Naegleria-like Cysts in Cretaceous Amber from Central Kansas. J.Eukaryot.Microbiol. 40(1):97-100, 1993

Reprint

In File

Notes

Fossil protist cysts are reported from the mid-Cretaceous amber of Ellsworth County, Kansas, which is rich in terrestrial microfossils but contains no known macrofossils. On the basis of their distinctive morphology, the cysts can be referred to the genus Naegleria (Schizopyrenida); they most closely resemble cysts of the living species Naegleria gruberi. This is the first known fossil record for this group of amoebas. The current phylogenetic position and paleoecological role of Naegleria are discussed in relation to this find; it provides direct confirmation of morphological stasis in this group, which had previously been inferred from rRNA sequence divergence data.