NEW PROCESS, GENUS AND FAMILY OF LOWER CRETACEOUS DIATOMS FROM AUSTRALIA

Abstract

A new process named “uvular” (L. uvular) was discovered in specimens of Lower Cretaceous (Aptian) diatoms during LM and SEM investigations. The morphology of this centrally-located process is a funnel-shaped depression with a round opening on the valve exterior and a uvula-shaped intrusion on the inside, without visible openings. Three new species are described and united in the new genus Archaegladiopsis Nikolaev & Harwood, based on the presence of the uvular process; these include Archaegladiopsis jacki, A. davidi and A. etheridgei. We separated these species from the genus Gladiopsis Gersonde & Harwood because the generitype, G. speciosus (Schulz) Gersonde & Harwood, possesses an annular (multistrutted) process. The new genus Archaegladiopsis warrants a new Family Archaegladiopsidaceae Nikolaev & Harwood.