A revision of the genus Cyclophora and description of Astrosyne gen. nov. (Bacillariophyta), two genera with the pyrenoids contained within pseudosepta

• DOI: 10.2216/12-004.1
• Publication Date: 2012-10-22T18:41:48Z
• Authors: Matt P. Ashworth; Elizabeth C. Ruck; Christopher S. Lo...; Dwight K. Romanovicz; Edward C. Theriot
• Keywords: Pyrenoid; Chlorophyceae; Incertae sedis; Frustule

Ashworth M.P., Ruck E.C., Lobban C.S., Romanovicz D.K., and Theriot E.C. 2012. A revision of the genus Cyclophora description Astrosyne gen. nov. (Bacillariophyta), two genera with pyrenoids contained within pseudosepta. Phycologia 51: 684–699. DOI: 10.2216/12-004.1The araphid pennate diatom is characterized by an elliptical to circular pseudoseptum at centre one valve; C. tenuis only commonly reported species. New species have included some pseudosepta on both valves, we emended generic accommodate these. Three were described from light scanning electron microscopy: castracanei sp. nov., tabellariformis minor Of these, was isovalvar a valves; heterovalvar but differed in shape type species; very small had iso- frustules. Other differences stria density arrangement slits apical fields. Developmentally, areolae boundary filled as grew. Also radiata which possessed valves radially symmetrical valve outline. Transmission microscopy (TEM) observations cytoplasmic ultrastructural organization three-gene sequencing (nuclear-encoded subunit rRNA, rbcL psbC) cultured cells carried out all except minor. TEM showed that localized Astrosyne. Phylogenetic analysis DNA sequences also supported close relationship between these genera. While A. not first suggested be derived lineage, localization central may most distinctive synaopomorphy amongst diatoms such different outlines.