Lepidoptera

Kristensen, Niels P., Scoble, Malcolm J. & Karsholt, Ole, 2007, Lepidoptera phylogeny and systematics: the state of inventorying moth and butterfly diversity, Zootaxa 1668, pp. 699-747 : 726

Fossil Lepidoptera

In none of the other major insect orders is the fossil record as poor as in the Lepidoptera . This is undoubtedly partly due to the special properties of their wings, which not only are particularly fragile because of the paucity (shared with caddisflies) of cross-veins and only moderate sclerotization of the principal longitudinal veins, but, and in particular, because the scale vestiture render them more un-wettable than other insect wings ( Wagner et al. 1996)—a factor that evidently impedes their fossilisation in lacustrine (or near-shore marine) sediments. No known fossil Lepidoptera represent organisation types that differ markedly from extant ones, and fossils have so far contributed little, if anything, to the understanding of phylogenetic interrelationships within the order. Nevertheless, fossils provide the only direct means for establishing the minimum ages of individual evolutionary lineages.

The fossil record of Lepidoptera (as of other insects) was recently reviewed by Grimaldi & Engel (2005), whose excellent account is recommended strongly. The oldest fossil currently believed to belong to the Lepidoptera is Archaeolepis manae from the Lower Jurassic (ca 190 MYO) and according to Grimaldi & Engel a recent re-examination of the specimen has given additional support to its ordinal placement. A small number of moths are known from younger Jurassic strata, but the first lepidopteran fossil that can with any certainty be assigned to a known family lineage (viz., Micropterigidae ) is from the Lower Cretaceous. The existence of Glossata also in the lower Cretaceous is documented by a larval fossil with a distinct spinneret, while reexamination of an alleged adult glossatan moth from the upper Jurassic failed to confirm the presence of a proboscis. Indeed the presence of glossatans of this age would be unexpected, if angiosperm feeding evolved in the stem lineage of Heterobathmiidae + Glossata. Following Labandeira et al. (1994), leaf mines from the Mid Cretaceous Dakota formation attributed to a member of Gracillariidae-Phyllocnistinae have been considered to demarcate the known minimum age of the Ditrysia. Nevertheless, Grimaldi & Engel rightly caution about the uncertainty inherent in identifying leaf miners. In any case there is little doubt that the main radiation of the Lepidoptera followed the main radiation of angiosperms in the Cretaceous. The point has repeatedly been made that since bat predation is probably the principal selective force behind the evolution of tympanal organs in nocturnal Lepidoptera , all the tympanate moths lineages (including such species-rich lineages as pyraloids, geometroids and noctuoids) cannot have predated the origin of bats whose currently known minimum age is Early Tertiary. The minimum age for the butterfly families Pieridae and Nymphalidae as estimated from molecular evolution is more than 70 MYO, hence the butterflies as a whole must be somewhat older ( Braby et al. 2006, Wahlberg 2006).