Fultoportula

A fultoportula is a process consisting of a central tube passing through the valve and two or more satellite pores that surround and support the central tube. Externally, the fultoportula appears as either a tube, or a simple pore in the valve wall. Internally, the satellite pores are visible.

The plural is fultoportulae. These processes are found only in the centric order Thalassiosirales. In Latin, the meaning is "strutted opening".

Fultoportulae are usually associated with the secretion of β-chitin fibrils which help to maintain buoyancy in the plankton by increasing the cell surface area.

Alternative Terms

strutted process: Used by Ross et al. (1979).

Citations

Cox, E.J. (2011) Morphology, cell wall, cytology, ultrastructure, and morphogenetic studies. Overview and specific observations. In: The Diatom World (J. Seckbach and J.P. Kociolek, Eds,), Cellular origin, life in extreme habitats and astrobiology, Vol. 19, pp. 21–45, Springer, Dordrecht.
Ross, R., Cox, E.J., Karayeva, N.I., Mann, D.G., Paddock, T.B.B., Simonsen, R. and Sims, P.A. (1979) An amended terminology for the siliceous components of the diatom cell Nova Hedwigia, Beihefte 64: 513-533
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.

Fultoportulae Ex — Image (also SEM) of the external view of *Stephanodiscus yellowstonensis*. The external expression of marginal fultoportulae is indicated by arrows; the marginal fultoportulae are positioned below spines.

Fultoportulae Int — SEM, internal view of valve of *Stephanodiscus* sp. showing the rimoportula (R), central fultoportula (CF) and four marginal fultoportulae (MF). Each fultoportula has two satellite pores surrounding the central tube.