Characterization, distribution, biology and impact on Italian walnut orchards of the invasive North-American leafminerCoptodisca lucifluella(Lepidoptera: Heliozelidae)

Abstract

The leafminer Coptodisca sp. (Lepidoptera: Heliozelidae), recently recorded for the first time in Europe on Italian black and common walnut trees, is shown to be the North-American Coptodisca lucifluella (Clemens) based on morphological (forewing pattern) and molecular (cytochrome oxidase c subunit I sequence) evidence. The phylogenetic relatedness of three species feeding on Juglandaceae suggests that C. lucifluella has likely shifted, within the same host plant family, from its original North-American hosts Carya spp. to Juglans spp. Over the few years since its detection, it has established in many regions in Italy and has become a widespread and dominant invasive species. The leafminer completes three to four generations per year, with the first adults emerging in April-May and mature larvae of the last generation starting hibernation in September-October. Although a high larval mortality was recorded in field observations (up to 74%), the impact of the pest was substantial with all leaves infested at the end of the last generation in all 3 years tested. The distribution of the leafminer in the canopy was homogeneous. The species is redescribed and illustrated, a lectotype is designated and a new synonymy is established.

A molecular phylogeny for the oldest (nonditrysian) lineages of extant Lepidoptera, with implications for classification, comparative morphology and life‐history evolution

“…Most of the species elsewhere in the world are contained in Heliozela , Antispila and Coptodisca , but Antispila Hübner is a composite ‘waste basket’ taxon, and several species need to be removed to the previously monotypic Holocacista Walsingham & Durrant (van Nieukerken & Geertsema, ). Coptodisca Walsingham is restricted to North and Central America (Bernardo et al , ). The adult female has a piercing oviscapt, and the larvae are usually leaf miners, with prolegs absent or nearly so and thoracic legs usually absent, although these are well developed and five‐segmented in some Heliozela (Davis, ).…”

DNA barcodes for bio-surveillance: regulated and economically important arthropod plant pests

“…More recently, DNA barcoding led to the recognition of a buprestid beetle, Agrilus ribesi, whose introduction to North America had been overlooked for a century (Jendek et al 2015). Barcoding has also been used to detect invasive tephritid fruit flies in Nigeria (Onah et al 2015), leafminers in Papua New Guinea (Blacket et al 2015) and Italy (Bernardo et al 2015), a stink bug (Halyomorpha halys) in Europe (Cesari et al 2015), and a cotton bug, Oxycarenus hyalinipennis, in Florida (Nagoshi et al 2012). Based on its effectiveness in species identification, the Quarantine Barcode of Life project (www.qbol.org) worked towards establishing DNA barcoding as the core technology for identifying quarantine organisms in support of plant health, and to gain its acceptance by the pest regulators as the standard method for the identification of plant pests (van de Vossenberg et al 2013).…”

Blowing in the wind: a unique aerial descent on a leaf in a caterpillar

“…, Bernardo et al. ). As for caterpillars living on leaf surfaces, a limacodid larva, Scopelodes contracta , completely cuts the basal part of a tree leaf, parachutes to the ground on the leaf, and spins a cocoon in the soil (Yamazaki ).…”

“…Some leafminers induce early leaf abscission from host trees and fall down to the ground within leaves, which allows pupation in the litter (Kahn andCornell 1983, Yamazaki andSugiura 2008). Antispila and Coptodisca (Heliozelidae) larvae cut leaf mines to make portable cases in the canopy and descend to the forest floor on silk threads for hibernation and pupation (van Nieukerken et al 2012, Bernardo et al 2015. As for caterpillars living on leaf surfaces, a limacodid larva, Scopelodes contracta, completely cuts the basal part of a tree leaf, parachutes to the ground on the leaf, and spins a cocoon in the soil (Yamazaki 2010).…”