After Olson, 1985, Feduccia, 1996, Sibley & Monroe, 1990, Livezey & Zusi, 2001, Mayr, 2004, 2005, and Sangster, 2005

<==o “Caprimulgiformes” (kehrääjälinnut; nightjars) [Recent: 22 genera / 115 species]
   |?- Steatornithidae (rasvalinnut) [paraphyletic??] [1/1]
   `--+--o “Podargidae traditionalis”
      |  |-- Podargidae (pöllökehrääjät) [1/3]
      |  `-- Batrachostomidae [subfamily of Podargidae??] [1/11]
      `--o Cypselomorphae Huxley, 1867 sensu Mayr, 2002
         |-- †Protocypselomorphus manfredkelleri Mayr, 2005; M.Eoc. CEu.
         |--o †Archaeotrogonidae Mourer-Chauviré, 1980
         |  |-- †Hassiavis laticauda Mayr, 1998; M.Eoc. CEu.
         |  `--o †Archaeotrogon
         |     |-- †A. venustus
         |     |-- †A. zitteli
         |     |-- †A. cayluxensis
         |     `-- †A. hoffstetteri
         `--+--o Caprimulgiformes sensu stricto
            |  |-- Nyctibiidae (pökkelökehrääjät) [1/7]
            |  `--o Caprimulgidae (nightjars; kehrääjät)
            |     |?- †Ventivorus ragei
            |     |-- Chordeilinae (haukkakehrääjät) [4/9]
            |     `-- Caprimulginae (varsinaiset kehrääjät) [13/77]
            `--o Daedalornithes Sangster, 2005
               |-- Aegothelidae (owlet-nightjars; australiankehrääjät) [1/7]
               `-- Apodiformes (swifts & hummingbirds; kirskulinnut) [Recent: 131 genera / 443 species]

Reference(s):