After Adl et al., 2005

<==o Choanomonada Kent, 1880 [Choanoflagellida] (collar-flagellates, choanoflagellates)
   |--o Monosigidae Zhukov & Karpov, 1985 [Conodosigidae Kent, 1880]
   |  |-- Codonosiga
   |  |-- Monosiga
   |  `-- Sphaeroeca
   |--o Salpingoecidae Kent, 1880
   |  |-- Salpingoeca
   |  `-- Stelexomonas
   `--o Acanthoecidae Norris, 1965
      |-- Bicosta
      `-- Stephanoeca

Reference(s):