A Global Phylogeny of Leafmining Ectoedemia Moths (Lepidoptera: Nepticulidae): Exploring Host Plant Family Shifts and Allopatry as Drivers of Speciation

Abstract

BackgroundHost association patterns in Ectoedemia (Lepidoptera: Nepticulidae) are also encountered in other insect groups with intimate plant relationships, including a high degree of monophagy, a preference for ecologically dominant plant families (e.g. Fagaceae, Rosaceae, Salicaceae, and Betulaceae) and a tendency for related insect species to feed on related host plant species. The evolutionary processes underlying these patterns are only partly understood, we therefore assessed the role of allopatry and host plant family shifts in speciation within Ectoedemia.MethodologySix nuclear and mitochondrial DNA markers with a total aligned length of 3692 base pairs were used to infer phylogenetic relationships among 92 species belonging to the subgenus Ectoedemia of the genus Ectoedemia, representing a thorough taxon sampling with a global coverage. The results support monophyletic species groups that are congruent with published findings based on morphology. We used the obtained phylogeny to explore host plant family association and geographical distribution to investigate if host shifts and allopatry have been instrumental in the speciation of these leafmining insects.SignificanceWe found that, even though most species within species groups commonly feed on plants from one family, shifts to a distantly related host family have occasionally occurred throughout the phylogeny and such shifts are most commonly observed towards Betulaceae. The largest radiations have occurred within species groups that feed on Fagaceae, Rosaceae, and Salicaceae. Most species are restricted to one of the seven global biogeographic regions, but within species groups representatives are commonly found in different biogeographic regions. Although we find general patterns with regard to host use and biogeography, there are differences between clades that suggest that different drivers of speciation, and perhaps drivers that we did not examine, have shaped diversity patterns in different clades.

Stigmella multispicata Rociene. & Stonis, an Asian leafminer on Siberian elm, now widespread in eastern North America (Lepidoptera, Nepticulidae)

“…Our methodology for DNA barcoding has been described in other papers (van Nieukerken et al 2012a, 2012c, Doorenweerd et al 2015, 2016). We present a Neighbor Joining tree, with KP2 distances, of the selected taxa, made with tools provided by BOLD Systems (Ratnasingham and Hebert 2007).…”

A new leafminer on grapevine and Rhoicissus (Vitaceae) in South Africa within an expanded generic concept of Holocacista (Insecta, Lepidoptera, Heliozelidae)

“…PCR conditions and primers are described in our earlier studies (van Nieukerken et al 2012a; van Nieukerken et al 2012b; Doorenweerd et al 2015). Sequencing was outsourced to Macrogen Corporation, Amsterdam or BaseClear B.V., Leiden.…”

A revised checklist of Nepticulidae fossils (Lepidoptera) indicates an Early Cretaceous origin

“…However, by a combination of recent stratigraphic evaluation of the Dakota Formation (Brenner et al 2000), and updates in global geochronological tie-points (Ogg et al 2008), the lower portion of the Dakota Formation is re-dated at 102 Ma. We consider it impossible that these mines are related to modern Platanus feeders in the genus Ectoedemia, which belong to a much later evolved, subordinate clade (Doorenweerd et al 2015), even though there is a superficial resemblance.…”

“…• # 33 Nepticulidae: incertae sedis Browniea DT91 Insect damage; Donovan et al 2014 The host family Cornaceae (including Nyssaceae, to which Browniea was originally assigned) is used as a host by some Ectoedemia in North-America (Doorenweerd et al 2015) and undescribed Acalyptris species in Asia (data EJvN). However, the mines of this record are different from the mines of extant Cornaceae-feeding species.…”

“…Many species are (strict) monophages or oligophages (sensu Menken & Roessingh 1998), and some genera or species groups are specialized on a single plant family. Several studies provide a phylogeny of the family or its subgroups (Scoble 1983, van Nieukerken 1986, Puplesis 1994, Hoare & van Nieukerken 2013, Doorenweerd et al 2015.…”