Abstract
The palm family generally has characteristic phytoliths with many conical projections. Diagnostic, amorphous spheroid, echinate phytoliths are present in all organs of the sago palm (Metroxylon sagu Rottb.), which constitute approximately 8–9% of leaflet dry weight. For phytolith observation, transmitted-light (TLM) and scanning electron microscopy (SEM) were used at x400 and x1000 magnifications. The terminal angles and length of conical projections were calculated according to Heron’s formula. The mean maximum diameter of phytoliths and the mean number, mean terminal angle, and mean length of conical projections of M. sagu were 13.2 μm, 26.0, 84.0°, and 0.54 μm, respectively, under TLM. Meanwhile, the phytoliths of M. sagu were 15.1 μm of the mean maximum diameter of phytoliths, 21.6 of the mean number of conical projections, 91.4° of the mean terminal angle of conical projections, and 1.45 μm of the conical projection lengths under SEM. It is possible to utilize spheroid echinate morphology, conical projections arranged at the periphery, and terminal angles and lengths of conical projections as indicators of the identification of M. sagu phytoliths.
https://ror.org/00f2txz25 
