A winged relative of ice ‐crawlers in amber bridges the cryptic extant Xenonomia and a rich fossil record

The origin of the distinctive xenonomian insects has been a matter of debate. The head morphology described here demonstrates that a new Cretaceous fossil is a crown Xenonomia. The new specimen bridges the species-poor extant Xenonomia clade with a rich Permian fossil record. AbstractUntil the advent of phylogenomics, the atypical morphology of extant representatives of the insect orders Grylloblattodea (ice-crawlers) and Mantophasmatodea (gladiators) had confounding effects on efforts to resolve their placement within Polyneoptera. This recent research has unequivocally shown that these species-poor groups are closely related and form the clade Xenonomia. Nonetheless, divergence dates of these groups remain poorly constrained, and their evolutionary history debated, as the few well-identified fossils, characterized by a suite of morphological features similar to that of extant forms, are comparatively young. Notably, the extant forms of both groups are wingless, whereas most of the pre-Cretaceous insect fossil record is composed of winged insects, which represents a major shortcoming of the taxonomy. Here, we present new specimens embedded in mid-Cretaceous amber from Myanmar and belonging to the recently described speciesAristovia daniili. The abundant material and pristine preservation allowed a detailed documentation of the morphology of the species, including critical head features. Combined with a morphological data set encompassing all Polyneoptera, these new data uneq...
Source: Insect Science - Category: Biology Authors: Tags: ORIGINAL ARTICLE Source Type: research