leucania unipuncta

armyworm \armyworm\, Army worm \Ar"my worm`\ (Zool.)
   (a) A lepidopterous insect, which in the larval state often
       travels in great multitudes from field to field,
       destroying grass, grain, and other crops. The common army
       worm of the northern United States is the noctuid moth
       ({Pseudaletia unipuncta}, formerly {Leucania unipuncta}.
       The name is often applied to other related species, as
       the cotton worm.
   (b) The larva of a small two-winged fly ({Sciara}), which
       marches in large companies, in regular order. See {Cotton
       worm}, under {Cotton}.

   Syn: army worm
        [1913 Webster]

   2. the larva of the fungus gnat; -- they march in large
      companies in regular order.
      [WordNet 1.5] Arna