Jean-François Landry

DNA barcodes for 1/1000 of the animal kingdom

This study reports DNA barcodes for more than 1300 Lepidoptera species from the eastern half of North America, establishing that 99.3 per cent of these species possess diagnostic barcode sequences. Intraspecific divergences averaged just 0.43 per cent among this assemblage, but most values were lower. The mean was elevated by deep barcode divergences (greater than 2%) in 5.1 per cent of the species, often involving the sympatric occurrence of two barcode clusters. A few of these cases have been analysed in detail, revealing species overlooked by the current taxonomic system. This study also provided a large-scale test of the extent of regional divergence in barcode sequences, indicating that geographical differentiation in the Lepidoptera of eastern North America is small, even when comparisons involve populations as much as 2800 km apart. The present results affirm that a highly effective system for the identification of Lepidoptera in this region can be built with few records per species because of the limited intra-specific variation. As most terrestrial and marine taxa are likely to possess a similar pattern of population structure, an effective DNA-based identification system can be developed with modest effort.

Allopatry as a Gordian Knot for Taxonomists: Patterns of DNA Barcode Divergence in Arctic-Alpine Lepidoptera

Many cold adapted species occur in both montane settings and in the subarctic. Their disjunct distributions create taxonomic complexity because there is no standardized method to establish whether their allopatric populations represent single or different species. This study employs DNA barcoding to gain new perspectives on the levels and patterns of sequence divergence among populations of 122 arctic-alpine species of Lepidoptera from the Alps, Fennoscandia and North America. It reveals intraspecific variability in the barcode region ranging from 0.00–10.08%. Eleven supposedly different species pairs or groups show close genetic similarity, suggesting possible synonymy in many cases. However, a total of 33 species show evidence of cryptic diversity as evidenced by the presence of lineages with over 2% maximum barcode divergence in Europe, in North America or between the two continents. Our study also reveals cases where taxonomic names have been used inconsistently between regions and exposes misidentifications. Overall, DNA barcodes have great potential to both increase taxonomic resolution and to make decisions concerning the taxonomic status of allopatric populations more objective.

Pyrosequencing for Mini-Barcoding of Fresh and Old Museum Specimens

DNA barcoding is an effective approach for species identification and for discovery of new and/or cryptic species. Sanger sequencing technology is the method of choice for obtaining standard 650 bp cytochrome c oxidase subunit I (COI) barcodes. However, DNA degradation/fragmentation makes it difficult to obtain a full-length barcode from old specimens. Mini-barcodes of 130 bp from the standard barcode region have been shown to be effective for accurate identification in many animal groups and may be readily obtained from museum samples. Here we demonstrate the application of an alternative sequencing technology, the four-enzymes single-specimen pyrosequencing, in rapid, cost-effective mini-barcode analysis. We were able to generate sequences of up to 100 bp from mini-barcode fragments of COI in 135 fresh and 50 old Lepidoptera specimens (ranging from 53–97 year-old). The sequences obtained using pyrosequencing were of high quality and we were able to robustly match all the tested pyro-sequenced samples to their respective Sanger-sequenced standard barcode sequences, where available. Simplicity of the protocol and instrumentation coupled with higher speed and lower cost per sequence than Sanger sequencing makes this approach potentially useful in efforts to link standard barcode sequences from unidentified specimens to known museum specimens with only short DNA fragments.

In the dark in a large urban park: DNA barcodes illuminate cryptic and introduced moth species

To facilitate future assessments of diversity following disturbance events, we conducted a first level inventory of nocturnal Lepidoptera in Stanley Park, Vancouver, Canada. To aid the considerable task, we employed high-throughput DNA barcoding for the rough sorting of all material and for tentative species identifications, where possible. We report the preliminary species list of 190, the detection of four new exotic species (Argyresthia pruniella, Dichelia histrionana, Paraswammerdamia lutarea, and Prays fraxinella), and the potential discovery of two cryptic species. We describe the magnitude of assistance that barcoding presents for faunal inventories, from reducing specialist time to facilitating the detection of native and exotic species at low density.

A Molecular Phylogeny for Yponomeutoidea (Insecta, Lepidoptera, Ditrysia) and Its Implications for Classification, Biogeography and the Evolution of Host Plant Use

Background Yponomeutoidea, one of the early-diverging lineages of ditrysian Lepidoptera, comprise about 1,800 species worldwide, including notable pests and insect-plant interaction models. Yponomeutoids were one of the earliest lepidopteran clades to evolve external feeding and to extensively colonize herbaceous angiosperms. Despite the group’s economic importance, and its value for tracing early lepidopteran evolution, the biodiversity and phylogeny of Yponomeutoidea have been relatively little studied. Methodology/Principal Findings Eight nuclear genes (8 kb) were initially sequenced for 86 putative yponomeutoid species, spanning all previously recognized suprageneric groups, and 53 outgroups representing 22 families and 12 superfamilies. Eleven to 19 additional genes, yielding a total of 14.8 to 18.9 kb, were then sampled for a subset of taxa, including 28 yponomeutoids and 43 outgroups. Maximum likelihood analyses were conducted on data sets differing in numbers of genes, matrix completeness, inclusion/weighting of synonymous substitutions, and inclusion/exclusion of “rogue” taxa. Monophyly for Yponomeutoidea was supported very strongly when the 18 “rogue” taxa were excluded, and moderately otherwise. Results from different analyses are highly congruent and relationships within Yponomeutoidea are well supported overall. There is strong support overall for monophyly of families previously recognized on morphological grounds, including Yponomeutidae, Ypsolophidae, Plutellidae, Glyphipterigidae, Argyresthiidae, Attevidae, Praydidae, Heliodinidae, and Bedelliidae. We also assign family rank to Scythropiinae (Scythropiidae stat. rev.), which in our trees are strongly grouped with Bedelliidae, in contrast to all previous proposals. We present a working hypothesis of among-family relationships, and an informal higher classification. Host plant family associations of yponomeutoid subfamilies and families are non-random, but show no trends suggesting parallel phylogenesis. Our analyses suggest that previous characterizations of yponomeutoids as predominantly Holarctic were based on insufficient sampling. Conclusions/Significance We provide the first robust molecular phylogeny for Yponomeutoidea, together with a revised classification and new insights into their life history evolution and biogeography.

Taxonomic review of the leek moth genus Acrolepiopsis (Lepidoptera: Acrolepiidae) in North America

The North American species of Acrolepiopsis are reviewed and include six described species: A. assectella (Zeller), A. californica Gaedike, A. heppneri Gaedike, A. incertella (Chambers), A. leucoscia (Meyrick), and A. reticulosa (Braun). Acrolepiopsis liliivora Gaedike is considered a junior synonym of A. californica (new synonymy). Acrolepiopsis assectella, commonly known as the leek moth, is a recently invasive alien species in North America and a pest of the plant genus Allium, including leek, onion, garlic, and related cultivated plants. A key to species based on adults is provided, diagnostic characters including male and female genitalia are illustrated, and geographical distribution, host plants, and larval feeding pattern and damage (where known) are given. Diagnostics and illustrations are presented also for A. sapporensis (Matsumura); known as the Asiatic onion leafminer, it is very similar to A. assectella and is an invasive alien species present in Hawaii, though not in North America. Adult diagnostic characters of the genus Acrolepiopsis, the family Acrolepiidae, and the superfamily Yponomeutoidea are also provided and illustrated. DNA barcoding data (short sequences of the mitochondrial cytochrome c oxidase I gene) obtained for five of the six species revealed interspecific differences averaging 8.1%, whereas intraspecific variation was ≤ 0.16%, and provided unequivocal species separation matching morphology-based identifications.

Larval case architecture and implications of host-plant associations for North American Coleophora (Lepidoptera; Coleophoridae)

The case-bearing moths of North America are represented by a single genus, Coleophora, which contains approximately 144 described species. All are external seed or leaf miners that inhabit portable silk cases during most of the larval stage. Architectural and ecological characters from larval cases were used in cladistic analysis to investigate existing case groups for 32 North American species of Coleophora. Cladistic analysis confirmed monophyly of certain case groups, but not of others. Host-plant preferences were also examined. The pattern of host plant use reflects more closely preference for certain plant tissues (seeds versus leaves) and growth forms (herbaceous versus woody) with exploitation of different plant taxa, rather than preference for certain plant taxa with exploitation of different plant tissues. q 2002 The Willi Hennig

DNA barcoding and morphology reveal three cryptic species of Anania (Lepidoptera: Crambidae: Pyraustinae) in North America, all distinct from their European counterpart

Anania coronata (Hufnagel), a Holarctic species of pyraustine crambid moth, has long been treated as having two geographically separated subspecies – the nominotypical Anania coronata in the Palaearctic Region and Anania coronata tertialis (Guenée) in the Nearctic Region. Maximum likelihood and Bayesian inference analysis of mitochondrial DNA barcodes both recover four well‐supported, reciprocally monophyletic groups within Anania coronata. Qualitative and quantitative analyses of genital structures reveal diagnostic differences that correspond to the four barcode lineages. On the basis of both molecular and morphological evidence, we conclude that Anania coronata is actually a complex of four species. Anania coronata (Hufnagel) is restricted to Europe, whereas three species occur in North America: Anania tertialis (Guenée), Anania plectilis (Grote & Robinson) and Anania tennesseensissp.n. Yang.

Plutella australiana (Lepidoptera, Plutellidae), an overlooked diamondback moth revealed by DNA barcodes.

Abstract The genus Plutella was thought to be represented in Australia by a single introduced species, Plutella xylostella (Linnaeus), the diamondback moth. Its status as a major pest of cruciferous crops, and the difficulty in developing control strategies has motivated broad-ranging studies on its biology. Prior genetic work has generally supported the conclusion that populations of this migratory species are connected by substantial gene flow. However, the present study reveals the presence of two genetically divergent lineages of this taxonin Australia. One shows close genetic and morphological similarity with the nearly cosmopolitan Plutella xylostella. The second lineage possesses a similar external morphology, but marked sequence divergence in the barcode region of the cytochrome c oxidase I gene, coupled with clear differences in genitalia. As a consequence, members of this lineage are described as a new species, Plutella australiana Landry & Hebert, which is broadly distributed in the eastern half of Australia.

Combining DNA barcoding and morphological analysis to identify specialist floral parasites (Lepidoptera: Coleophoridae: Momphinae: Mompha)

Close interactions between insects and plants have played a major role in the evolution of both these diverse groups of organisms. Studying these interactions, however, can be difficult because many insects, especially parasites, impinge most strongly on plants during larval stages when they are morphologically difficult to identify, and many belong to diverse groups for which most species remain undescribed. We used DNA barcoding to identify nondescript lepidopteran larvae that regularly parasitize flower buds of the coastal dune endemic Camissoniopsis cheiranthifolia (Onagraceae). We obtained cytochrome oxidase 1 mitochondrial DNA sequences from 201 parasite specimens from across the host geographical range. The Barcode of Life Database Identification System combined with Bayesian analysis grouped all 15 parasite haplotypes in a distinct, monophyletic clade within the genus Mompha (Lepidoptera: Coleophoridae: Momphinae), a group known to be host specialists on plants of the Onagraceae. Species identity and phylogenetic affinities within Mompha could not be confirmed because few barcode sequences exist from this diverse and poorly known group of moths. However, morphological analysis, including detailed dissection of genitalia for a subsample of 23 reared adults and comparison with known species of Mompha, also indicated that the larvae parasitizing C. cheiranthifolia constitute a distinct and undescribed species within this genus. Knowing that floral parasitism of C. cheiranthifolia involves a single, putatively host‐specific microlepidopteran greatly facilitates formulating and testing hypotheses concerning how floral parasitism has promoted the evolution of striking floral diversity within this species. More generally, DNA barcoding combined with morphological analysis can greatly hasten identification of problematic specimens and enhance our understanding of the diversity, ecology and evolution of plant–insect interactions.