Ptychopteridae is an ancient and rather diverse nematoceran family with three extant and 12 fossil genera subdivided into 80 extinct species belonging to five subfamilies (Eskov & Lukashevich, 2015; Lukashevich, 2019, 2020; Liu & Huang, 2020). Several undescribed ptychopterid larvae from the Upper Triassic of Germany represent the oldest record of the family (Barth et al., 2011). Crenoptychoptera Kalugina, 1985, an extinct genus belonging to the subfamily Eoptychopterinae Handlirsch, 1906, includes seven described species. All these species were recorded from the Lower Jurassic to the Lower Cretaceous of Eurasia: C. dobbertinensis Ansorge, 1998 from the Lower Jurassic of the Former Clay in Germany (Lukashevich et al., 1998), C. conspecta Lukashevich, 1995 from the Lower Jurassic of Ust-Baley in Russia (Lukashevich, 1995), the type species C. antica Kalugina, 1985 and C. defossa Kalugina, 1985 from the Middle Jurassic of the Kubekovo in Russia (Kalugina & Kovalev, 1985), C. bavarica Krzemiński & Ansorge, 1995 from the Upper Jurassic of Wegscheid in Germany (Krzemiński & Ansorge, 1995), C. liturata Lukashevich, 2011 from Upper Jurassic of Shar Teg in Mongolia, and C. gronskayae Kalugina, 1989 from the Upper Jurassic to Lower Cretaceous of Kempendyay in Russia (Kalugina, 1989; Lukashevich, 2011). Three species discovered from the Daohugou beds of China have been assigned to Crenoptychoptera (Hao et al., 2009), but a following study suggested that they should be placed in Axymyiidae (Zhang, 2010).
