Guide to Terpsinoë
- Valves elongate, margins undulate
- Valve center with rimoportula
- Porefields present at valve apices
- Transverse costae distinct
Terpsinoë is a multipolar, 'centric' diatom. The frustules are heavily silicified and elongate, with strongly undulate margins. Porefields are located at the valve apices. Internal, heavily silicified transverse costae are present. In girdle view, the transverse costae appear to form the shape of musical notes. Rimoportulae are positioned near the center of the valve face.
Terpsinoë grows commonly in tropical and subtropical regions, often on oceanic islands. In the US, Terpsinoë is known from groundwater springs in Texas (San Marco Springs) and Florida rivers (Wekiwa).