Epitheca

An epitheca is the larger half of a frustule. The epitheca overlaps the hypotheca. In Greek epitheca means outer sheath.

See also frustule, hypotheca, valve, and cingulum.

Round, F.E., Crawford, R.M. and Mann, D.G. (1990) The Diatoms. Biology and Morphology of the Genera. Cambridge University Press, Cambridge, 747 pp.