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International audience; Background: Herbivorous insects represent a major fraction of global biodiversity and the relationships they have established with their food plants range from strict specialists to broad generalists. Our knowledge of these relationships is of primary importance to basic (e.g. the study of insect ecology and evolution) and applied biology (e.g. monitoring of pest or invasive species) and yet remains very fragmentary and understudied. In Lepidoptera, caterpillars of families Saturniidae and Sphingidae are rather well known and considered to have adopted contrasting preferences in their use of food plants. The former are regarded as being rather generalist feeders, whereas the latter are more specialist. New information: To assemble and synthesise the vast amount of existing data on food plants of Lepidoptera families Saturniidae and Sphingidae, we combined three major existing databases to produce a dataset collating more than 26,000 records for 1256 species (25% of all species) in 121 (67%) and 167 (81%) genera of Saturniidae and Sphingidae, respectively. This dataset is used here to document the level of polyphagy of each of these genera using summary statistics, as well as the calculation of a polyphagy score derived from the analysis of Phylogenetic Diversity of the food plants used by the species in each genus.

Two species complexes within the genus Xylophanes are addressed using a combination of morphological study and analysis of DNA barcode sequences. The existence of two and three cryptic species respectively within the X. loelia and X. neoptolemus complexes is revealed following consideration of both adult habitus and genital morphology, and the results of a phylogenetic analysis of partial COI sequences—DNA barcodes—for 38 specimens. The taxonomic status of the available names is discussed and to clarify and stabilize the confused nomenclature of this group, a neotype for Sphinx neoptolemus Cramer, 1780, and lectotypes for Choerocampa loelia Druce, 1878 and Chaerocampa trilineata Walker, [1865], are designated. We describe three new species: X. lolita n. sp. Vaglia and Haxaire; X. balcazari n. sp. Haxaire and Vaglia; and X. cthulhu n. sp. Haxaire and Vaglia. The first is endemic to southeastern Brazil and closely allied to X. loelia; the second two are relatives of X. neoptolemus, of which the first is known only from Guerrero and Michoacán states in Mexico while the second is widely distributed in lowland forests of Central America.

The authors review the taxonomy of the group of species related to Cechenena aegrota (Butler, 1875). They demonstrate that the species in Sundaland, which most authors have referred to by this name, is not this species but a separate taxon, Cechenena chimaera (Rothschild, 1894). True aegrota is a more modest looking insect found further north on mainland Asia, from Sikkim to Vietnam. The habitus, male genitalia and distributions of the two species, together with those of the related Cechenena transpacífica (Clark, 1923), are described and illustrated.The status of the other synonyms of C. aegrota are discussed., Sur l'identité de Cechenena aegrota (Butler, 1875) et des espèces proches (Lepidoptera, Sphingidae). Les auteurs révisent le groupe des espèces apparentées à Cechenena aegrota (Butler, 1875). Ils démontrent que, dans la littérature, ce que la grande majorité des auteurs désignent sous ce nom n'est pas cette espèce, mais C. chimaera (Rothschild, 1894). Le vrai aegrota est un insecte d'allure plus modeste, et volant beaucoup plus au nord, du Sikkim au Vietnam. Les répartitions des deux espèces sont présentées et visualisées sur une carte, les habitus et les génitalia de ces deux taxons ainsi que ceux de l'espèce-sœur de chimaera, C. transpacifica (Clark, 1923), sont illustrés. Les statuts des autres synonymes de C. aegrota sont débattus., Haxaire Jean, Kitching Ian J. On the identity of Cechenena aegrota (Butler, 1875) and related species (Lepidoptera, Sphingidae). In: Bulletin de la Société entomologique de France, volume 108 (4), octobre 2003. pp. 355-360.

Description of a new Hawk-moth from French Guiana, Manduca duquefi (Lepidoptera, Sphingidae). Manduca duquefi n. sp. is described from one male collected at Petit Saut (French Guiana). From its pattern it is closed to M. reducta (Gehlen, 1930), but the genitalia show that it is most closely related to M. contracta (Butler, 1875)., Manduca duquefi n. sp. est décrit à partir d'un mâle collecté à Petit-Saut (Guyane française). Par l'habitus, il se positionne à côté de M. reducta (Gehlen, 1930), mais ses pièces génitales l'apparentent plutôt à M. contracta (Butler, 1875)., Haxaire Jean, Vaglia Thierry. Description d'un nouveau Sphinx de Guyane française, Manduca duquefi (Lepidoptera, Sphingidae). In: Bulletin de la Société entomologique de France, volume 112 (3), septembre 2007. pp. 331-333.

Main objectiveWe examine the extent of taxonomic and biogeographical uncertainty in a well-studied group of Australian Lepidoptera, the hawkmoths (Sphingidae).MethodsWe analysed the diversity of Australian sphingids through the comparative analysis of their DNA barcodes, supplemented by morphological re-examinations and sequence information from a nuclear marker in selected cases. The results from the analysis of Australian sphingids were placed in a broader context by including conspecifics and closely related taxa from outside Australia to test taxonomic boundaries.ResultsOur results led to the discovery of six new species in Australia, one case of erroneously synonymized species, and three cases of synonymy. As a result, we establish the occurrence of 75 species of hawkmoths on the continent. The analysis of records from outside Australia also challenges the validity of current taxonomic boundaries in as many as 18 species, including Agrius convolvuli (Linnaeus, 1758), a common species that has gained adoption as a model system. Our work has revealed a higher level of endemism than previously recognized. Most (90%) Australian sphingids are endemic to the continent (45%) or to Australia, the Pacific Islands and the Papuan and Wallacean regions (45%). Only seven species (10%) have ranges that extend beyond this major biogeographical boundary toward SE Asia and other regions of the Old World.Main conclusionsThis study has established that overlooked cryptic diversity and inaccurate species delineation produced significant misconceptions concerning diversity and distribution patterns in a group of insects that is considered well known taxonomically. Because DNA barcoding represents a straightforward way to test taxonomic boundaries, its implementation can improve the accuracy of primary diversity data in biogeography and conservation studies.

International audience; The hawkmoth genus Manduca is a diverse group of very large, conspicuous moths that has served as an important model across many biological disciplines. Two species in particular, the tobacco hornworm (Manduca sexta) and the tomato hornworm (Manduca quinquemaculatus) have been researched extensively. Studies across biological fields have referred to these two species as being closely related or even sister species, but the extent to which these two model organisms are related remains largely unknown. We conducted a comprehensive multi-gene phylogenetic analysis of Manduca, based on both an ML and Bayesian framework, which resulted in a monophyletic Manduca but only when two other genera, Dolba and Einyglottis are included. We tentatively conclude that the sister group to Manduca sexta comprises the Caribbean M. afflicta and M. johanni, and the sister lineage to this clade includes M. quinquemaculatus and the Hawaiian M. blackburni. Thus, M. sexta and M. quinquemaculatus are closely related, but are not sister species. Biogeographical analyses reveal an ancestral center of diversification in Central America, and Manduca appears to have subsequently colonized North and South America. Our phylogeny provides an important foundation for comparative studies of two model organisms and their relatives. (C) 2013 Elsevier Inc. All rights reserved.

Interspecific hybridisation is a rare but widespread phenomenon identified as a potential complicating factor for the identification of species through DNA barcoding. Hybrids can, however, also deceive morphology-based taxonomy, resulting in the description of invalid species based on hybrid specimens. As the result of an unexpected case of discordance between barcoding results and current morphology-based taxonomy, we discovered an example of such a hybrid ‘species’ in hawkmoths. By combining barcodes, morphology and a nuclear marker, we show that Gnathothlibus collardi Haxaire, 2002 is actually an F1 hybrid between two closely related species that co-occur on Tahiti. In accordance with the International Code of Zoological Nomenclature, the taxon G. collardi is thus invalid as a species. This study demonstrates the potential of DNA barcodes to detect overlooked hybrid taxa. With the growth of sequence libraries, we anticipate that more unsuspected hybrid species will be detected, particularly among those taxa that are very rare, such as those known from only the type specimen.

Background When a specimen belongs to a species not yet represented in DNA barcode reference libraries there is disagreement over the effectiveness of using sequence comparisons to assign the query accurately to a higher taxon. Library completeness and the assignment criteria used have been proposed as critical factors affecting the accuracy of such assignments but have not been thoroughly investigated. We explored the accuracy of assignments to genus, tribe and subfamily in the Sphingidae, using the almost complete global DNA barcode reference library (1095 species) available for this family. Costa Rican sphingids (118 species), a well-documented, diverse subset of the family, with each of the tribes and subfamilies represented were used as queries. We simulated libraries with different levels of completeness (10-100% of the available species), and recorded assignments (positive or ambiguous) and their accuracy (true or false) under six criteria. Results A liberal tree-based criterion assigned 83% of queries accurately to genus, 74% to tribe and 90% to subfamily, compared to a strict tree-based criterion, which assigned 75% of queries accurately to genus, 66% to tribe and 84% to subfamily, with a library containing 100% of available species (but excluding the species of the query). The greater number of true positives delivered by more relaxed criteria was negatively balanced by the occurrence of more false positives. This effect was most sharply observed with libraries of the lowest completeness where, for example at the genus level, 32% of assignments were false positives with the liberal criterion versus < 1% when using the strict. We observed little difference (< 8% using the liberal criterion) however, in the overall accuracy of the assignments between the lowest and highest levels of library completeness at the tribe and subfamily level. Conclusions Our results suggest that when using a strict tree-based criterion for higher taxon assignment with DNA barcodes, the likelihood of assigning a query a genus name incorrectly is very low, if a genus name is provided it has a high likelihood of being accurate, and if no genus match is available the query can nevertheless be assigned to a subfamily with high accuracy regardless of library completeness. DNA barcoding often correctly assigned sphingid moths to higher taxa when species matches were unavailable, suggesting that barcode reference libraries can be useful for higher taxon assignments long before they achieve complete species coverage.