Hyles Euphorbiae Research Articles

High-quality haploid genomes corroborate 29 chromosomes and highly conserved synteny of genes in Hyles hawkmoths (Lepidoptera: Sphingidae)

BackgroundMorphological and traditional genetic studies of the young Pliocene genus Hyles have led to the understanding that despite its importance for taxonomy, phenotypic similarity of wing patterns does not correlate with phylogenetic relationship. To gain insights into various aspects of speciation in the Spurge Hawkmoth (Hyles euphorbiae), we assembled a chromosome-level genome and investigated some of its characteristics.ResultsThe genome of a male H. euphorbiae was sequenced using PacBio and Hi-C data, yielding a 504 Mb assembly (scaffold N50 of 18.2 Mb) with 99.9% of data represented by the 29 largest scaffolds forming the haploid chromosome set. Consistent with this, FISH analysis of the karyotype revealed n = 29 chromosomes and a WZ/ZZ (female/male) sex chromosome system. Estimates of chromosome length based on the karyotype image provided an additional quality metric of assembled chromosome size. Rescaffolding the published male H. vespertilio genome resulted in a high-quality assembly (651 Mb, scaffold N50 of 22 Mb) with 98% of sequence data in the 29 chromosomes. The larger genome size of H. vespertilio (average 1C DNA value of 562 Mb) was accompanied by a proportional increase in repeats from 45% in H. euphorbiae (measured as 472 Mb) to almost 55% in H. vespertilio. Several wing pattern genes were found on the same chromosomes in the two species, with varying amounts and positions of repetitive elements and inversions possibly corrupting their function.ConclusionsOur two-fold comparative genomics approach revealed high gene synteny of the Hyles genomes to other Sphingidae and high correspondence to intact Merian elements, the ancestral linkage groups of Lepidoptera, with the exception of three simple fusion events. We propose a standardized approach for genome taxonomy using nucleotide homology via scaffold chaining as the primary tool combined with Oxford plots based on Merian elements to infer and visualize directionality of chromosomal rearrangements. The identification of wing pattern genes promises future understanding of the evolution of forewing patterns in the genus Hyles, although further sequencing data from more individuals are needed. The genomic data obtained provide additional reliable references for further comparative studies in hawkmoths (Sphingidae).

A survey on sphingidae (lepidoptera) species of south eastern Turkey with new distributional records

This paper provides comments on the Sphingidae species of south eastern Turkey by the field surveys are conducted between in 2015-2017. A total of 15 species are determined as a result of the investigations from Batman, Diyarbakır and Mardin provinces. With this study, the number of sphinx moths increased to 13 in Batman, 14 in Diyarbakır and 8 in Mardin. Among them, 7 species for Batman, 4 species for Diyarbakır and 1 species for Mardin are new record. For each species, original reference, type locality, material examined, distribution in the world and in Turkey, and larval hostplants are given. Adults figures of Smerinthus kindermanni Lederer, 1852; Marumba quercus ([Denis & Schiffermüller], 1775); Rethera komarovi (Christoph, 1885); Macroglossum stellatarum (Linnaeus, 1758); Hyles euphorbiae (Linnaeus, 1758) and H. livornica (Esper, [1780]) are illustrated.

Functional characterization of the Hyles euphorbiae hawkmoth transcriptome\xa0reveals strong expression of phorbol ester detoxification and seasonal cold hardiness genes

BackgroundThe European spurge hawkmoth, Hyles euphorbiae (Lepidoptera, Sphingidae), has been intensively studied as a model organism for insect chemical ecology, cold hardiness and evolution of species delineation. To understand species isolation mechanisms at a molecular level, this study aims at determining genetic factors underlying two adaptive ecological trait candidates, phorbol ester (TPA) detoxification and seasonal cold acclimation.MethodA draft transcriptome of H. euphorbiae was generated using Illumina sequencing, providing the first genomic resource for the hawkmoth subfamily Macroglossinae. RNA expression levels in tissues of experimental TPA feeding larvae and cooled pupae was compared to levels in control larvae and pupae using 26 bp RNA sequence tag libraries (DeepSuperSAGE). Differential gene expression was assessed by homology searches of the tags in the transcriptome.ResultsIn total, 389 and 605 differentially expressed transcripts for detoxification and cold hardiness, respectively, could be identified and annotated with proteins. The majority (22 of 28) of differentially expressed detox transcripts of the four ‘drug metabolism’ enzyme groups (cytochrome P450 (CYP), carboxylesterases (CES), glutathione S-transferases (GST) and lipases) are up-regulated. Triacylglycerol lipase was significantly over proportionally annotated among up-regulated detox transcripts. We record several up-regulated lipases, GSTe2, two CESs, CYP9A21, CYP6BD6 and CYP9A17 as candidate genes for further H. euphorbiae TPA detoxification analyses. Differential gene expression of the cold acclimation treatment is marked by metabolic depression with enriched Gene Ontology terms among down-regulated transcripts almost exclusively comprising metabolism, aerobic respiration and dissimilative functions. Down-regulated transcripts include energy expensive respiratory proteins like NADH dehydrogenase, cytochrome oxidase and ATP synthase. Gene expression patterns show shifts in carbohydrate metabolism towards cryoprotectant production. The Glycolysis enzymes, G1Pase, A1e, Gpi and an Akr isoform are up-regulated. Glycerol, an osmolyte which lowers the body liquid supercooling point, appears to be the predominant polyol cryoprotectant in H. euphorbiae diapause pupae. Several protein candidates involved in glucose, glycerol, myo-inositol and potentially sorbitol and trehalose synthesis were identified. ConclusionsA majority of differently expressed transcripts unique for either detoxification or cold hardiness indicates highly specialized functional adaptation which may have evolved from general cell metabolism and stress response.The transcriptome and extracted candidate biomarkers provide a basis for further gene expression studies of physiological processes and adaptive traits in H. euphorbiae.

The Generalist Inside the Specialist: Gut Bacterial Communities of Two Insect Species Feeding on Toxic Plants Are Dominated by Enterococcus sp.

Some specialist insects feed on plants rich in secondary compounds, which pose a major selective pressure on both the phytophagous and the gut microbiota. However, microbial communities of toxic plant feeders are still poorly characterized. Here, we show the bacterial communities of the gut of two specialized Lepidoptera, Hyles euphorbiae and Brithys crini, which exclusively feed on latex-rich Euphorbia sp. and alkaloid-rich Pancratium maritimum, respectively. A metagenomic analysis based on high-throughput sequencing of the 16S rRNA gene revealed that the gut microbiota of both insects is dominated by the phylum Firmicutes, and especially by the common gut inhabitant Enterococcus sp. Staphylococcus sp. are also found in H. euphorbiae though to a lesser extent. By scanning electron microscopy, we found a dense ring-shaped bacterial biofilm in the hindgut of H. euphorbiae, and identified the most prominent bacterium in the biofilm as Enterococcus casseliflavus through molecular techniques. Interestingly, this species has previously been reported to contribute to the immobilization of latex-like molecules in the larvae of Spodoptera litura, a highly polyphagous lepidopteran. The E. casseliflavus strain was isolated from the gut and its ability to tolerate natural latex was tested under laboratory conditions. This fact, along with the identification of less frequent bacterial species able to degrade alkaloids and/or latex, suggest a putative role of bacterial communities in the tolerance of specialized insects to their toxic diet.

Pollination of a threatened orchid by an introduced hawk moth species in the tallgrass prairie of North America

The decline of the threatened western prairie fringed orchid (Platanthera praeclara Sheviak and Bowles) is associated with destruction of the tallgrass prairie in North America. The role of pollinators in conservation and recovery is not well understood. We studied interactions with hawk moth pollinators in one of the three remaining metapopulations of P. praeclara. In an experiment, plants exposed to moths showed three signs of visitation that were associated with production of seed capsules. Plants not exposed to moths failed to produce capsules. The signs of visitation were used to estimate visitation rates at field sites over a four-year period. A majority of plants were visited (89%) and most flowers receiving pollen produced a seed capsule (60%). We discovered two new native hawk moth pollinator species, Lintneria eremitus (Hübner) and Hyles lineata (Fabricius), giving a total of five pollinators for this P. praeclara metapopulation. Only one of the five species was found in each of the nine years of trapping. This was the sole non-native pollinator, Hyles euphorbiae L., a Eurasian species introduced to North America to control an invasive weed, leafy spurge (Euphorbia esula L.).Given that plants with a greater diversity of pollinators have reduced risk of extinction, conservation and recovery plans should expand the definition of suitable P. praeclara habitat to include resources required by native pollinators, including the host plants that feed hawk moth larvae and the nectar plants that feed hawk moth adults before and after the nectar provided by P. praeclara.

Larval pattern morphotypes in the Western Palaearctic Hyles euphorbiae complex (Lepidoptera: Sphingidae: Macroglossinae)

AbstractExternal morphological variation in larval pattern elements in the Hyles euphorbiae complex is documented and described from independent samples of numerous populations across Europe and North Africa. Variability in the distribution of black cuticle and other colours was found to be much higher within populations than previously believed and it proved difficult to characterize any species, subspecies and even local population unequivocally using this feature alone. A representative sample of larvae from the Canary Islands, Madeira, North Africa, Iberia, Italy, Germany, Eastern Europe, Malta, Greece and Yemen, is illustrated, supplemented by observations from photographs of larvae from the Middle East and Western Asia. Taxonomy-independent definitions of larval morphotypes demonstrate significant overlap between species. We discuss the results in the context of Western Palaearctic biogeography, postulating several areas of hybridisation between the more northern Hyles euphorbiae and more southern H. tithymali that have led to the mosaic distribution patterns observed, and consider the potential of these moths for tracking the future eff ects of climate change in the Mediterranean Basin.

Eleven hawkmoth microsatellite loci of Canary Island Hyles tithymali (Lepidoptera)

We describe the first eleven microsatellite loci for hawkmoths in Hyles tithymali from the Canary Islands. They are polymorphic with 3–13 alleles per locus, an expected heterozygosity between 0.18 and 0.86, and an observed heterozygosity between 0.11 and 0.68. As typical for Lepidoptera, the yield of new loci was low due to the presence of microsatellite gene families, mildly repetitive and variable flanking regions. These first microsatellites provide informative results in population studies of Hyles tithymali, a thermophilic species hybridising with Hyles euphorbiae in the Mediterranean.

Experimental population genetics in insects: inheritance of ISSR-PCR bands in an artificial population

Inter-simple sequence repeat (ISSR)-PCR fingerprints are being increasingly used to establish relationships between closely related animals, although their inheritance patterns have not been examined closely as yet. To better understand the genetics of this relatively novel genomic fingerprint technique and to assess the tokogenetic information content of the data for the Hyles euphorbiae (Linnaeus, 1758) complex (HEC; Lepidoptera: Sphingidae) precisely, we examined five separated pairs of moths of Hyles euphorbiae from Spain (10 moths) and their offspring as an artificial population. ISSR-PCR fingerprints were obtained with four primers and the 0/1 matrix analysed. The cluster algorithm Neighbour Joining was successful in reconstructing the families as monophyletic, although intra-familial cluster formation cannot be represented by a dichotomous branching pattern. In contrast, the band sharing index did not detect significant differences in variability between siblings and individuals of H. euphorbiae from different localities compared at random. Rather high levels of recombination were detected, which surprisingly did not appear to obscure the tokogenetic signal to a significant degree. Thus ISSR-PCR fingerprints appear to be appropriate markers to study relationships between HEC individuals of two consecutive generations, while being too variable for higher levels.

Revisiting Leafy Spurge Biocontrol: A Case Study

History of Biocontrol Introductions Biological control efforts were expanded in North Dakota in the mid-1980s7 (Table 1). The stem-boring beetle (Oberea erythrocephala), the hawk moth (Hyles euphorbiae), and the gall midge (Spurgia esulae) are established at low population levels throughout the state.8 In addition, four Aphthona species are also established in North Dakota. Aphthona fl ava is established but shows a slow population increase.7 A. nigriscutis was originally the most successful biocontrol agent;9 however, a mixed population of black beetles, A. czwalinae and A. lacertosa, reproduced and expanded rapidly in the mid-1990s and became the most successful Aphthona species in reducing the leafy spurge.9,10 Successful establishment of Aphthona is variable along with its effectiveness in controlling leafy spurge across variable habitats in North Dakota.7,9,11 Temperature, moisture, soil type, ground cover, slope, and/or associated vegetation at release sites affects fl ea beetle survival and establishment10,12 with different Aphthona species exhibiting differing preferences to these factors.13 Post-establishment monitoring is an important aspect of classical biological control. However, limited quantitative post-establishment data are available, especially, for Aphthona spp.

Introduced leafy spurge hawkmoth, Hyles euphorbiae L., appears in Saskatoon

Introduced leafy spurge hawkmoth, Hyles euphorbiae L., appears in Saskatoon

A New species of Hyles (Lepidoptera, Sphingidae) from Mongolia with Distributional Notes on the other Members of the Genus

A new species of Hyles, Hyles churkini sp. nova, is described from S-W Mongolia. This new species is compared with other Mongolian Hyles species and a brief description of their habitats is presented. Hyles chamyla (Denso, 1913) and Hyles euphorbiae (Linnaeus, 1758) were first recorded in Mongolia. The pictures of Hyles zygophylli xanthophyli (Derzhavets, 1977) are presented for the first time.

Sequestration of phorbol esters by aposematic larvae of Hyles euphorbiae (Lepidoptera: Sphingidae)?

The larvae of the hawkmoth species Hyles euphorbiae have a conspicuous aposematic colouration and show gregarious behaviour. It has thus been suggested that they sequester phorbol esters from their food plants which include different species of the genus Euphorbia (Euphorbiaceae) for chemical protection against predators. To test this hypothesis in more detail, we fed larvae an artificial diet with three doses of 12-tetradecanoyl-phorbol-13-acetate (TPA), then examined the faeces and the larval tissues, such as integument, haemolymph and gut of the caterpillars for the presence of TPA. In order to determine the ability of the larvae to detoxify phorbol esters, other larvae were directly injected with a TPA solution and analysed in the same manner. Our study indicates that the larvae of Hyles euphorbiae do not sequester phorbol esters. Upon oral application TPA was not found in the larval integument or the haemolymph. Instead, it was mostly metabolised (about 70–90%). Nevertheless, about 10-30% were retained and recovered in the faeces. The larvae were also able to metabolise and thus detoxify the phorbol ester when TPA was injected directly into the body. These hawkmoth caterpillars are relatively large and have a gut full of plant material, which they regurgitate into the direction of the predator when attacked in nature. Since phorbol esters are very potent toxins and irritants, we postulate that the gut content (and especially the plant slurry disgorged as regurgitant from the anterior gut) alone could be aversive for a potential predator, even if some metabolism has taken place. Thus, although H. euphorbiae caterpillars do not actively sequester phorbol esters, their aposematic colouration appears to be based on chemical defence through phorbol esters retained in the gut.

Survival of Leafy Spurge Hawk Moths (Hyles euphorbiae) When Larvae Are Exposed to 2,4-D or Picloram

Larvae of the leafy spurge hawk moth were sprayed with and/or were fed leafy spurge plants sprayed with 2,4-D or picloram. Larval survival was not affected from contact with the chemicals, from feeding on contaminated foliage, or from a combination of both. Viable second-generation adult moths were produced in all treatments. Thus, leafy spurge infested with the leafy spurge hawk moth can be sprayed with 2,4-D or picloram without injury to larvae that have reached the fourth or fifth instar stages.