Dasyleptus is an extinct genus of wingless insects, and the only member of the family Dasyleptidae and order or suborder Monura. They resembled juveniles of their modern relatives and had a single lengthy filament projecting from the end of the abdomen. They also had a pair of leg-like cerci and some non-ambulatory abdominal appendages. The largest specimens reached or more, not counting the length of the filament. Dasyleptus species are mostly known only from the Late Carboniferous and Permian, but one species recorded from the Middle Triassic indicates that they survived the Permian–Triassic extinction event. Dasyleptus and Monura are now typically treated as members of the living order Archaeognatha, though this placement was questioned in a 2026 study, which found it to be a stem-group insect and the most primitive insect known.
Taxonomy The genus includes the following species:
Dasyleptus artinskianus – Early Permian (Artinskian), Wellington Formation, Kansas, United States Dasyleptus brongniarti – Middle Permian (Roadian), Mitina Formation, Kuznetsk Basin, Russia Dasyleptus lucasi (type species) – Late Carboniferous (Gzhelian), Commentry Shales, France Dasyleptus noli – Late Carboniferous (Gzhelian), Commentry Shales, France Dasyleptus rowlandi – Early Permian (Asselian), Bursum Formation, New Mexico, United States Dasyleptus sharovi – Early Permian (Artinskian), Wellington Formation, United States Dasyleptus sinensis – Late Permian/Early Triassic, Kayitou Formation, China Dasyleptus triassicus – Middle Triassic (Ladinian), Meride Limestone, Monte San Giorgio, Switzerland
Phylogeny Position of Dasyleptus after Tihelka et al. 2026, placing it outside of the Archaeognatha and crown insects as a whole.
See also Tonganoxichnus, a trace fossil attributed to Monura
References