Figure above :  Wing-venation of a number of representatives of the family Chironomidae  ( = Tendipedidae)
      ( Nematocera).
      Reading from left to right and from top to bottom :
      53 -- Trichotanypus  nigriventris KIEFF.
      54 -- Polypedulum  nubeculosum MEIG.
      55 -- Thienemanniella  spec.