After Whittington, Chang, Dean, Fortey, Jell, Laurie, Palmer, Repina, Rushton & Shergold, 1997, Gon, 2002 and Lieberman, 2001

<==o †Holmiinae Hupé, 1953 [taxonomic history]
   |--o †Holmia Matthew, 1890
   |  `-- †H. kjerulfi (Linnarsson, 1873 [1871?]) [Paradoxides kjerulfi Linnarsson, 1873]
   |--o †Andalusiana Sdzuy, 1961
   |  `-- †A. cornuta Sdzuy, 1961
   |--o †Cambropallas Geyer, 1993
   |  `-- †C. telesto Geyer, 1993
   |--o †Elliptocephala Emmons, 1844
   |  |-- †E. asaphoides Walcott, 1910 [non Emmons, 1844?]
   |  `-- †E. logani (Walcott)
   |--o †Esmeraldina Resser & Howell, 1938
   |  `-- †E. rowei (Walcott, 1910) [Holmia rowei Walcott, 1910]
   |--o †Holmiella Fritz, 1972
   |  `-- †H. preancora Fritz, 1972
   |--o †Iyouella Geyer & Palmer, 1995
   |  `-- †I. contracta Geyer & Palmer, 1995
   |--o †Palmettaspis Fritz, 1995
   |  `-- †P. consorta Fritz, 1995
   |--o †Schmidtiellus Moberg in Moberg & Segerberg, 1906
      |--o †S. mickwitzi (Schmidt, 1888) [Olenellus mickwitzi Schmidt, 1888]
      |  |-- †S. m. mickwitzi (Schmidt, 1888)
      |  `-- †S. m. torelli (Moberg, 1899) [Olenellus mickwitzi torelli Moberg, 1899]
      `-- †S. reetae

Reference(s):