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Name derivation:
Greek Diplo meaning double;neis is derived from naus; Latin navis: ship (Silva 1980)
Classification:
Diploneis Cleve, P.T. 1894; 85 of 508 species have been flagged as currently accepted taxonomically. OrderNaviculales; Family Diploneidaceae
Morphology:
Found as single cells usually lying in valve view. Valves can be linear to elliptical with bluntly rounded poles and in some species, the middle of the cell is constricted. The raphe lies in the middle of the cell, with two large continous longitudinal canals on each side. Striations vary from species to species. Each cell has two plastids on either side of the apical plane, containing one pyrenoid.
Similar genera:
Some species of Diploneis are oval and similiar in shape to Caloneis. The longitudinal canals on each side of the raphe distinguishes Diploneis from Caloneis. Some species of Diploneis that have a constricted mid-section resemble Cymatopleura. Once again the distinguishing characteristic is the two channels running down each side of the raphe in the center of the valve face. Cymatopleura also has a keel.
Habitat:
Found in both marine and freshwater habitats. Diploneis fenestrata, a new aerophilic diatom is described from Lumangwe falls, Zambia. This novel species occurs as an epiphyte on the roots and stems of trees located within the spray zone of the falls. Its morphology was examined with both light and scanning electron microscopy. D. fenestrata is distinguished from other taxa in the genus Diploneis by its prominent square openings ranging in number from 4-14 occurring within the area of the longitudinal canal only at the outer cell wall (Taylor et. al 2014).
References:
Round, F. E., Crawford, R. M., Mann, D. G. 1990. The Diatoms. Cambridge University Press. New York, NY. Silva, P.C. 1980. Names of classes and genera of living algae. Balm, Schellema & Holkema, Utrecht dr. W. junk b.v., Publishers, The Hague. Taylor, J.C., B. Karthick, C. Cocquyt and P. Lang 2014. Diploneis fenestrata sp nov (Bacillariophyta), a new aerophilic diatom species from Zambia, Africa. Phytotaxa 167(1): 79-82. Wehr, J., Sheath, R. 2003. Freshwater Algae of North America Ecology and Classification. Academis Press. San Diego, CA.