Comment on Phylogenetic analyses with four new Cretaceous bristletails reveal inter-relationships of Archaeognatha and Gondwana origin of Meinertellidae

Archaeognatha (Machilida plus dagger Monura), with similar to 450 extant species worldwide, represent a key lineage for the understanding of insect evolution. In a recently published phylogenetic analysis on Archaeognatha, based on a total-evidence approach, a Machilidae key fossil (Gigamachilis triassicus) from the Middle Triassic Lagerstatte of Monte San Giorgio and a representative of dagger Monura (Dasyleptus triassicus) from the same fossiliferous site, were not considered. In the present study, the phylogenetic analyses performed by Zhang et al. (2018) using maximum parsimony and Bayesian inference were repeated including these two key taxa; in addition, Tricholepidion gertschi and Lepisma saccharina were included as representatives of Zygentoma. In the total-evidence Bayesian analysis, dagger Monura was found to be paraphyletic, whereas in the maximum parsimony analysis, performed only on morphological characters, they were monophyletic. Moreover, the attribution of G. triassicus to Machilidae is now confirmed by these analyses, indicating that members of the extant group of Machilidae were already present in the Middle Triassic, at least similar to 100 Myr before the previous estimate.