Helcomyzidae is a small family of 13 species in 6 genera. Six species
  in 3 genera occur only in the Holarctic Region and 7 species in 3 genera
  occur only in far southern regions. Only 2 species are recorded from the
  Australasian/Oceanian Regions. Hennig (1973) listed Icaridion from
  the Campbell Is in the Helcomyzidae. It is treated in this catalog in the
  Coelopidae. 
  
  Immature stages of some northern species are known to develop in seaweed
  lying on shores and the adults frequent beaches.
  Ref.: Harrison (1959, NZ gen.).
MAORIMYIA Tonnoir & Malloch, 1928: 155. Type species: Trigonometopus
  bipunctatus Hutton, 1901, orig. des.
  bipunctata Hutton, 1901: 86 (Trigonometopus). NZ (Chatham
  Is); NZ (NZ).
PARACTORA Bigot, 1887f: 33. Type species: Paractora fuegiana Bigot, 1887 [= Heteromyza rufipes Macquart, 1843], mon.
  ACTOCELES Enderlein, 1912e: 43. Type species: Actoceles abscondita Enderlein, 1912, orig. des.
  asymmetrica Enderlein, 1930d: 259 (Actoceles). Macquarie I.