Proboscia alata

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Taxonomic Group:Diatom
Trophic Status:Autotrophic
Size Range:7-18 μm wide x up to 1 mm long (Cupp 1943, Horner 2002); 2.5-13 μm wide (Tomas 1997)
Key Characteristics:Cells cylindrical, straight, and long; valves end in short tube-like processes that resemble an elephant's trunk; depression at base of tube accepts process of adjacent cell; numerous small chloroplasts
Confused With:At first glance, with a single cell Lioloma pacificum, which is also extremely elongate, but is a pennate diatom with one square end, the other with a flattened foot pole
Toxin:None known