After Emig & Pardo, 2003- ["The BrachNet"], and Benedetto, 2007

<==o †Orthida Schuchert & Cooper, 1932
   |?- †Bethia serraticulma Sutton, Briggs, Siveter & Siveter, 2005
   |--o †Orthidina Schuchert & Cooper, 1932
   |  |--o †Orthoidea
   |  |  |-- †Productorthidae
   |  |  `--o †Heterorthidae
   |  |     `--o †Tarfaya Havlícek, 1971
   |  |        |?- †T. grandis (Harrington, 1938) Villas & Herrera, 2004 [Eoorthis grandis Harrington, 1938; Nanorthis grandis (Harrington) Castellaro, 1963; Nanorthis? grandis (Harrington) Benedetto, 2007]
   |  |        `-- †T. marocana Havlícek, 1971
   |  `--o †Plectorthoidea Schuchert & LeVene, 1929
   |     |?- †Diplonorthis Mitchell, 1977
   |     |?- †Cyrtonotella Schuchert & Cooper, 1931
   |     |-- †Nanorthidae Havlícek, 1977
   |     `--o †Euorthisinidae Havlícek, 1977
   |        |?- †Lesserorthis havliceki Benedetto, 2007
   |        |-- †Protorthisina simplex Benedetto, 2007
   |        `--o †Euorthisina Havlícek, 1950
   |           |-- †E.? nazarenensis Benedetto, 2007
   |           |-- †E. moesta (Barrande, 1879) [Orthisina moesta Barrande, 1879] [type]
   |           |-- †E. kobayashii Havlícek & Branisa, 1980 [incl.? E. orthiformis Havlícek & Branisa, 1980 (Benedetto, 2007)]
   |           |-- †E. parva Xu & Liu, 1984
   |           `-- †E. paucicostata Xu & Liu, 1984
   `--o †Dalmanellidina
      |-- †Dalmanelloidea
      `-- †Enteletoidea

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