Ten new and four known taxa of the diatom genus Actinocyclus are described, illustrated, and (or) noted from middle Miocene lake deposits in the Western United States. A key is presented to help separate the taxa based on morphological criteria visible in the light microscope. The geologic ranges of Actinocyclus species in the Western United States are discussed based on examination of over 100 localities of diatomaceous lacustrine deposits.
Additional publication details
Publication type:
Report
Publication Subtype:
USGS Numbered Series
Title:
The diatom genus Actinocyclus in the Western United States
