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Name derivation:
Classification:
Craticula Grunow 1867; 44 of 56 species descriptions are currently accepted taxonomically (Guiry and Guiry 2015. Order Bacillariophycidae; Family Naviculinaeae; 20 of 137 species descriptions are currently accepted taxonomically. Some taxonomists consider this genus to be unacceptable, because craticular stages are monstrosities belonging to other genera (Ibid.).
Morphology:
Symmetric biraphe unicells with raphe along apical axis of valve. Has prominent costae (thickened bars at right angles to long axis.   At least some species are polymorphic along gradients of salinity (Fuelling, in Diatoms of the United States, online)..
Similar genera:
Habitat:
Marine and freshwater, especially streams and rivers.
References:
Grunow, A. (1868 '1867'). Algae. In: Travel the Austrian frigate Novara Around the World in 1857, 1858, 1859 under the command of Commodore B. von Wüllerstorf-Urbair. Botanical Theil. First volume. Spore plants. (Fenzl, E. et al. Eds) Guiry, M.D. and G.M. Guiry 2015. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 17 January 2013.