After terrestrialization, the diversification of arthropods and vertebrates is thought to have occurred in two distinct phases1, the first between the Silurian and the Frasnian stages (Late Devonian period) (425–385 million years (Myr) ago), and the second characterized by the emergence of numerous new major taxa, during the Late Carboniferous period (after 345 Myr ago). These two diversification periods bracket the depauperate vertebrate Romer’s gap (360–345 Myr ago) and arthropod gap (385–325 Myr ago)1, which could be due to preservational artefact2,3. Although a recent molecular dating has given an age of 390 Myr for the Holometabola4, the record of hexapods during the Early–Middle Devonian (411.5–391 Myr ago, Pragian to Givetian stages) is exceptionally sparse and based on fragmentary remains, which hinders the timing of this diversification. Indeed, although Devonian Archaeognatha are problematic5,6, the Pragian of Scotland has given some Collembola and the incomplete insect Rhyniognatha, with its diagnostic dicondylic, metapterygotan mandibles5,7. The oldest, definitively winged insects are from the Serpukhovian stage (latest Early Carboniferous period)8. Here we report the first complete Late Devonian insect, which was probably a terrestrial species. Its ‘orthopteroid’ mandibles are of an omnivorous type, clearly not modified for a solely carnivorous diet. This discovery narrows the 45-Myr gap in the fossil record of Hexapoda, and demonstrates further a first Devonian phase of diversification for the Hexapoda, as in vertebrates, and suggests that the Pterygota diversified before and during Romer’s gap.
Access optionsAccess options
Subscribe to Journal
Get full journal access for 1 year
only $3.90 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
We thank O. Béthoux who discovered and prepared most of the arthropod material from Strud including the specimen described herein. We also thank G. Budd and G. Edgecombe for discussion on the fossil material and improving the first version of the paper, Gesves local council staff and field workers of the Strud expeditions, G. Odebert and S. Fernandez for preparing illustrations, and C. Lemzaouda and O. Béthoux for photographs of the associated arthropod fauna. Thanks are due to A. Folie for our request of a catalogue number for the specimen described herein (requests for materials can be sent to firstname.lastname@example.org). This work was partly supported by the French National Agency under the TERRES project (number ANR-2010-BLAN-607). Support for M.S.E. was provided by US National Science Foundation grant DEB-0542909.
This file contains Supplementary Text and Supplementary Figures 1-4. This file was replaced on 5 October 2012.
About this article