Glossary
Like the rest of this website, the glossary is a work in progress. If we’ve missed a term, please contact us to let us know the term and references.
Capitate
Capitate describes a valve end, or apex, as having the shape of a head, or the shape of a rounded knob.
Other terms for valve ends include subcapitate (less strongly capitate), rostrate, and subrostrate (less strongly rostrate). Subcapitate and subrostrate are quite similar and many taxa may be described as having subcapitate to subrostrate valve ends.
In general, capitate and subcapitate ends are more expanded than the narrowest point on the valve, while rostrate and subrostrate ends are not more expanded than the narrowest point.
Image Credit: Sarah Spaulding
Image Credit: Marina Potapova
Image Credit: Marina Potapova
Image Credit: Sarah Spaulding
The headpole of Didymosphenia geminata is distinctly capitate.
Image Credit: Marina Potapova
The valve ends of Planothidium haynaldii are broadly capitate.
Image Credit: Marina Potapova
The ends of Achnanthidium dutheii are capitate.