Papilio phylogeny based on mitochondrial cytochrome oxidase I and II genes

Genetic diversity, population structure and ecological niche modeling of Thyrinteina arnobia (Lepidoptera: Geometridae), a native Eucalyptus pest in Brazil

Thyrinteina arnobia (Lepidoptera: Geometridae) is a native American species. Despite its historical importance as an insect pest in Eucalyptus plantations, more information is needed regarding the population diversity, demography, and climatic variables associated with its distribution in different regions of Brazil. We used a phylogeographic approach to infer the genetic diversity, genetic structure, and demographic parameters of T. arnobia. We also conducted an ecological niche modeling (ENM) to predict suitable areas for T. arnobia occurrence in Brazil and other countries worldwide. Although T. arnobia populations have low genetic diversity in Brazil, we identified mitochondrial haplogroups predominating in different Brazilian regions and high ФST and ФCT values in AMOVA, suggesting a low frequency of insect movement among these regions. These results indicate that outbreaks of T. arnobia in Eucalyptus areas in different regions of Brazil are associated with local or regional populations, with no significant contribution from long-distance dispersal from different regions or biomes, suggesting that pest management strategies would be implemented on a regional scale. In Brazil, the demographic and spatial expansion signals of T. arnobia seem to be associated with the history of geographical expansion of Eucalyptus plantations, a new sustainable host for this species. ENM indicated that isothermality and annual rainfall are critical climatic factors for the occurrence of T. arnobia in tropical and subtropical areas in the Americas. ENM also suggested that T. arnobia is a potential pest in Eucalyptus areas in all Brazilian territory and in regions from Africa, Asia, and Oceania.

Phylogenetic and Comparative Genomics Study of Papilionidae Based on Mitochondrial Genomes

Most species of Papilionidae are large and beautiful ornamental butterflies. They are recognized as model organisms in ecology, evolutionary biology, genetics, and conservation biology but present numerous unresolved phylogenetic problems. Complete mitochondrial genomes (mitogenomes) have been widely used in phylogenetic studies of butterflies, but mitogenome knowledge within the family Papilionidae is limited, and its phylogeny is far from resolved. In this study, we first report the mitogenome of Byasa confusa from the subfamily Papilioninae of Papilionidae. The mitogenome of B. confusa is 15,135 bp in length and contains 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and an AT-rich control region (CR), closely mirroring the genomic structure observed in related butterfly species. Comparative analysis of 77 Papilionidae mitogenomes shows gene composition and order to be identical to that of an ancestral insect, and the AT bias, Ka/Ks, and relative synonymous codon usage (RSCU) are all consistent with that of other reported butterfly mitogenomes. We conducted phylogenetic analyses using maximum-likelihood (ML) and Bayesian-inference (BI) methods, with 77 Papilionidae species as ingroups and two species of Nymphalidae and Lycaenidae as outgroups. The phylogenetic analysis indicated that B. confusa were clustered within Byasa. The phylogenetic trees show the monophyly of the subfamily Papilioninae and the tribes Leptocircini, Papilionini, and Troidini. The data supported the following relationships in tribe level on Papilioninae: (((Troidini + Papilionini) + Teinopalpini) + Leptocircini). The divergence time analysis suggests that Papilionidae originated in the late Creataceous. Overall, utilizing the largest number of Papilionidae mitogenomes sequenced to date, with the current first exploration in a phylogenetic analysis on Papilionidae (including four subfamilies), this study comprehensively reveals the mitogenome characteristics and mitogenome-based phylogeny, providing information for further studies on the mitogenome, phylogeny, evolution, and taxonomic revision of the Papilionidae family.

Montane diversification as a mechanism of speciation in neotropical butterflies

The mountains in the Atlantic Forest domain are environments that harbor a high biodiversity, including species adapted to colder climates that were probably influenced by the climatic variations of the Pleistocene. To understand the phylogeographic pattern and assess the taxonomic boundaries between two sister montane species, a genomic study of the butterflies Actinote mantiqueira and A. alalia (Nymphalidae: Acraeini) was conducted. Analyses based on partial sequences of the mitochondrial gene COI (barcode region) failed to recover any phylogenetic or genetic structure discriminating the two species or sampling localities. However, single nucleotide polymorphisms gathered using Genotyping-by-Sequencing provided a strong isolation pattern in all analyses (genetic distance, phylogenetic hypothesis, clustering analyses, and F ST statistics) which is consistent with morphology, separating all individuals of A. alalia from all populations of A. mantiqueira. The three sampled mountain ranges where A. mantiqueira populations occur-Serra do Mar, Serra da Mantiqueira, and Poços de Caldas Plateau-were identified as three isolated clusters. Paleoclimate simulations indicate that both species' distributions changed according to climatic oscillations in the Pleistocene period, with the two species potentially occurring in areas of lower altitude during glacial periods when compared to the interglacial periods (as the present). Besides, a potential path between their distribution through the Serra do Mar Mountain range was inferred. Therefore, the Pleistocene climatic fluctuation had a significant impact on the speciation process between A. alalia and A. mantiqueira, which was brought on by isolation at different mountain summits during interglacial periods, as shown by the modeled historical distribution and the observed genetic structure.

A comprehensive phylogeny and revised taxonomy illuminate the origin and diversification of the global radiation of Papilio (Lepidoptera: Papilionidae)

The swallowtail genus Papilio (Lepidoptera: Papilionidae) is species rich, distributed worldwide, and has broad morphological habits and ecological niches. Because of its elevated species richness, it has been historically difficult to reconstruct a densely sampled phylogeny for this clade. Here we provide a taxonomic working list for the genus, resulting in 235 Papilio species, and assemble a molecular dataset of seven gene fragments representing ca. 80% of the currently described diversity. Phylogenetic analyses reconstructed a robust tree with highly supported relationships within subgenera, although a few nodes in the early history of the Old World Papilio remain unresolved. Contrasting with previous results, we found that Papilio alexanor is sister to all Old World Papilio and that the subgenus Eleppone is no longer monotypic. The latter includes the recently described Fijian Papilio natewa with the Australian Papilio anactus and is sister to subgenus Araminta (formerly included in subgenus Menelaides) occurring in Southeast Asia. Our phylogeny also includes rarely studied (P. antimachus, P. benguetana) or endangered species (P. buddha, P. chikae). Taxonomic changes resulting from this study are elucidated. Molecular dating and biogeographic analyses indicate that Papilio originated ca. 30 million years ago (Oligocene), in a northern region centered on Beringia. A rapid early Miocene radiation in the Paleotropics is revealed within Old World Papilio, potentially explaining their low early branch support. Most subgenera originated in the early to middle Miocene followed by synchronous southward biogeographic dispersals and repeated local extirpations in northern latitudes. This study provides a comprehensive phylogenetic framework for Papilio with clarification of subgeneric systematics and species taxonomic changes enumerated, which will facilitate further studies to address questions on their ecology and evolutionary biology using this model clade.

One Species, Hundreds of Subspecies? New Insight into the Intraspecific Classification of the Old World Swallowtail (Papilio machaon Linnaeus, 1758) Based on Two Mitochondrial DNA Markers

The Old World swallowtail Papilio machaon Linnaeus, 1758 is one of the most well-known and most characteristic members of the family Papilionidae. Over the past two centuries, the butterfly has been the subject of many studies. P. machaon is characterised by a tendency to change the wing colour pattern. In turn, due to the great interest of collectors and amateur entomologists, these studies have been converted into the description of over 100 colour forms, aberrations and subspecies. In this study, mitochondrial DNA (mtDNA), 16S rDNA and cytochrome b sequences were used to examine the correlation between the intraspecific classification and genetic structure of P. machaon. The study used 87 specimens from 59 different localities covering the geographic distribution of this species in the Palaearctic. The phylogenetic relationships within and between the Old World swallowtail subspecies showed that the intraspecific classification proposed by various authors does not correlate with the variability in mitochondrial DNA sequences. In addition, populations occurring at the species distribution borders in the Palaearctic Region (i.e., Japan, Kamchatka, Morocco and Sakhalin) are genetically distinct from other species.

Differentiation patterns of emperor moths (Lepidoptera: Saturniidae: Saturniinae) of a continental island: divergent evolutionary history driven by Pleistocene glaciations

Background

On the basis of molecular dating, Pleistocene glaciations have been proposed as the major driving force of biota speciation in the Palearctic and the pre-Quaternary origin of Amazonian taxa. However, the major driving factors in East Asia remain unclear. All 16 saturniine species inhabiting Taiwan with congeners of populations, subspecies, or species in East Asia constitute research objects for addressing the mode of speciation because of the repeated formation and disappearance of a landbridge from the Asian mainland to Taiwan during glacial cycles.

Methods

The genetic divergences of mitochondrial cytochrome c oxidase subunit I (COI) and 16S rDNA and the nuclear 28S rDNA of the saturniine species from Taiwan and the Asian mainland were assessed to determine the monophyly of each genus and species of Saturniinae. Moreover, 519 saturniine COI sequences of 114 taxa from adjacent East and Southeast Asian populations and closely related species were retrieved from GenBank and analyzed. The differentiation timing and possible origination of the insular saturniines were elucidated based on phylogenetic relationships, haplotype networks, and lineage calibrations.

Results

Approximately 90% of intraspecific COI divergence was <2%; all divergences exceeding 2% originated from comparisons between allopatric populations or subspecies. Relationship analyses revealed that multiple introductions likely occurred in insular saturniines and that some East Asian saturniines were paraphyletic as deduced by analyzing endemic insular species. Calibration dating revealed that Taiwanese endemic saturniines split from sibling Asian species 0.2-2.7 million years ago (Mya), whereas subspecific-level and population-level splitting events occurred 0.1-1.7 Mya and 0.2-1.2 Mya, respectively. Moreover, phylogenetic patterns combined with geographical distributions revealed that hill-distributed Taiwanese saturniines are closely related to those from southern China and Southeast Asia, whereas saturniines inhabiting altitudes higher than 1,500 m in Taiwan have siblings distributed in temperate Northeast Asia.

Discussion

The Global DNA Barcoding Initiative was successfully applied to study the population genetic structure in species. Most Formosan saturniines are distinct and monophyletic, reflecting the vicariant barrier of the Taiwan Strait; Pleistocene glacial cycles provided opportunities for insular saturniines to experience repeated isolation from and secondary contact with the continental mainland. Each insular saturniine may have evolved with a unique differentiation timing pattern that possibly emerged in the Early, Middle, or Late Pleistocene with these patterns differing from the consistent pattern that occurred in the temperate Palearctic and tropical Amazonian regions. Moreover, multiple migrations or artificial genetic admixtures may have also occurred, as suggested by the coexistence of two divergent lineages in a few Taiwanese saturniines.

Complete mitochondrial genome of Papilio elwesi and its phylogenetic analyses with other swallowtail butterflies (Lepidoptera, Papilionidae)

The complete mitochondrial genome of Papilio elwesi was sequenced and annotated using high-throughput sequencing in the present study. The mitochondrial genome (mitogenome) is a circular molecule of 15,082 bp in length, containing 37 genes (13 protein-coding genes, 22 transfer RNA genes, and two ribosomal RNA genes) and a putative control region. We performed mitogenomic phylogenetic analyses of 34 swallowtail species employing methods of Bayesian inference and maximum-likelihood. Our results further confirm that P. elwesi is a member of the subgenus Pterourus in Papilio sensu lato.

Spatial and host related genomic variation in partially sympatric cactophagous moth species

Surveys of patterns of genetic variation in natural sympatric and allopatric populations of recently diverged species are necessary to understand the processes driving intra- and interspecific diversification. The South American moths Cactoblastis cactorum, Cactoblastis doddi and Cactoblastis bucyrus are specialized in the use of cacti as host plants. These species have partially different geographic ranges and differ in patterns of host plant use. However, there are areas that overlap, particularly, in northwestern Argentina, where they are sympatric. Using a combination of genome-wide SNPs and mitochondrial data we assessed intra and interspecific genetic variation and investigated the relative roles of geography and host plants on genetic divergence. We also searched for genetic footprints of hybridization between species. We identified three well delimited species and detected signs of hybridization in the area of sympatry. Our results supported a hypothetical scenario of allopatric speciation in the generalist C. cactorum and genetic interchange during secondary geographic contact with the pair of specialists C. bucyrus and C. doddi that probably speciated sympatrically. In both cases, adaptation to new host plants probably played an important role in speciation. The results also suggested the interplay of geography and host plant use as drivers of divergence and limiting gene flow at intra and interspecific levels.

A New and Rare Actinote Hübner (Lepidoptera: Nymphalidae: Heliconiinae: Acraeini) from Southeastern Brazil

The present paper describes a new species of Actinote (Nymphalidae, Heliconiinae, Acraeini), Actinote keithbrowni Freitas, Francini & Mielke sp. nov., from southeastern Brazil, based on morphological and molecular data. The new species is very similar in wing pattern to Actinote eberti, within what we term the "light-gray mimicry complex." The host plants and immature stages of the new species are unknown. Actinote keithbrowni sp. nov. is one of the rarest species of Actinote from Brazil: in total, only eight individuals of this species are known from a narrow region of the Itatiaia massif despite years of collecting effort in that region since the 1940s.

Gene flow across host-associated populations of the rice stem borer Chilo suppressalis Walker (Lepidoptera: Crambidae): implications for Bt resistance management in rice

BACKGROUND

The rice stem borer, Chilo suppressalis, is a serious pest of rice, but also damages an aquatic vegetable, water oats (Zizania latifolia Turcz.). The time at which mating occurs is different between populations of rice stem borer associated with rice and those associated with water-oats, which suggests that undetected cryptic species may be associated with these plant hosts. If true, this would have significant management implications. This study is the first empirical test of this idea, using population genetic tools from two sampling cohorts. We genotyped 320 rice stem borer individuals from 2014, collected from rice and water-oats across five locations (where they exist in sympatry), using seven microsatellite loci.

RESULTS

We found no genetic structuring associated with host plant species. On water oats, some rice stem borers were found that had a similar mating time to the rice population, so in 2016, a second cohort of samples was screened by their timing of mating to get 'pure rice feeders' and 'pure water oats feeders'. These samples were genotyped with microsatellites, mitochondrial DNA (mtDNA) (COI and COII), and a nuclear gene (EF1-α). Our mtDNA data suggest a relatively low amount of population subdivision associated with plant host, but the microsatellite data revealed no such genetic structure, and we were only able to identify one haplotype of EF1-α.

CONCLUSIONS

Our results indicate gene flow between rice and water oats populations of rice stem borer, indicating that water oats will likely provide a refuge for resistance management of Bt rice. © 2019 Society of Chemical Industry.

Review of Molecular Identification Techniques for Forensically Important Diptera

The medico-legal section of forensic entomology focuses on the analysis of insects associated with a corpse. Such insects are identified, and their life history characteristics are evaluated to provide information related to the corpse, such as postmortem interval and time of colonization. Forensically important insects are commonly identified using dichotomous keys, which rely on morphological characteristics. Morphological identifications can pose a challenge as local keys are not always available and can be difficult to use, especially when identifying juvenile stages. If a specimen is damaged, certain keys cannot be used for identification. In contrast, molecular identification can be a better instrument to identify forensically important insects, regardless of life stage or specimen completeness. Despite more than 20 yr since the first use of molecular data for the identification of forensic insects, there is little overlap in gene selection or phylogenetic methodology among studies, and this inconsistency reduces efficiency. Several methods such as genetic distance, reciprocal monophyly, or character-based methods have been implemented in forensic identification studies. It can be difficult to compare the results of studies that employ these different methods. Here we present a comprehensive review of the published results for the molecular identification of Diptera of forensic interest, with an emphasis on evaluating variation among studies in gene selection and phylogenetic methodology.

Phylogeography of the gall-inducing micromoth Eucecidoses minutanus Brèthes (Cecidosidae) reveals lineage diversification associated with the Neotropical Peripampasic Orogenic Arc

We investigated the molecular phylogenetic divergence and historical biogeography of the gall-inducing micromoth Eucecidoses minutanus Brèthes (Cecidosidae) in the Neotropical region, which inhabits a wide range and has a particular life history associated with Schinus L. (Anacardiaceae). We characterize patterns of genetic variation based on 2.7 kb of mitochondrial DNA sequences in populations from the Parana Forest, Araucaria Forest, Pampean, Chacoan and Monte provinces. We found that the distribution pattern coincides with the Peripampasic orogenic arc, with most populations occurring in the mountainous areas located east of the Andes and on the Atlantic coast. The phylogeny revealed a marked geographically structured differentiation, which highlights a first split into two major clades: western (Monte and Chacoan) and eastern (Pampean and coastal forests). Together with AMOVA and network analysis, phylogeny revealed the existence of six well-defined lineages, which are isolated by distance. The TMRCA for Eucecidoses was estimated at ca. 65 Mya, and the divergence among major clades occurred by the Plio-Pleistocene ca. 20-25 Mya, with the extant six lineages emerging about 0.9 to 5.7 Mya (later than the rise of Schinus). These results are associated with a diversification pattern of either a late burst of speciation or early extinction. Population range expansion for some lineages concurring with major climatic changes that occurred during the wet-dry events of the Pleistocene in the region was recovered in both neutrality tests and past dynamics through time analysis. A possible biogeographic scenario reconstructed suggests that Eucecidoses likely emerged from a central meta-population in the south and later dispersed (ca. 38 Mya) using western and eastern as two major routes. Thus, a combination of dispersal and vicariance events that occurred in the ancestral populations might have shaped the current distribution of extant lineages. Speciation driven by host plant shift is potentially involved in the evolutionary history of Eucecidoses.

Influence of Wolbachia infection on mitochondrial DNA variation in the genus Polytremis (Lepidoptera: Hesperiidae)

The maternally inherited obligate bacteria Wolbachia is known for infecting the reproductive tissues of a wide range of arthropods and can contribute to phylogenetically discordant patterns between mtDNA and nDNA. In this study, we tested for an association between mito-nuclear discordance in Polytremis and Wolbachia infection. Six of the 17 species of Polytremis were found to be infected with Wolbachia. Overall, 34% (70/204) of Polytremis specimens were Wolbachia positive and three strains of Wolbachia identified using a wsp marker were further characterized as six strains based on MLST markers. Wolbachia acquisition in Polytremis appears to occur mainly through horizontal transmission rather than codivergence based on comparison of the divergence times of Wolbachia and Polytremis species. At the intraspecific level, one of the Wolbachia infections (wNas1) is associated with reduced mtDNA polymorphism in the infected Polytremis population. At the interspecific level, there is one case of mito-nuclear discordance likely caused by introgression of P. fukia mtDNA into P. nascens driven by another Wolbachia strain (wNas3). Based on an absence of infected males, we suspect that one Wolbachia strain (wNas2) affects sex ratio, but the phenotypic effects of the other strains are unclear. These data reveal a dynamic interaction between Polytremis and Wolbachia endosymbionts affecting patterns of mtDNA variation.

A preliminary molecular phylogeny of shield-bearer moths (Lepidoptera: Adeloidea: Heliozelidae) highlights rich undescribed diversity

Heliozelidae are a widespread, evolutionarily early diverging family of small, day-flying monotrysian moths, for which a comprehensive phylogeny is lacking. We generated the first molecular phylogeny of the family using DNA sequences of two mitochondrial genes (COI and COII) and two nuclear genes (H3 and 28S) from 130 Heliozelidae specimens, including eight of the twelve known genera: Antispila, Antispilina, Coptodisca, Heliozela, Holocacista, Hoplophanes, Pseliastis, and Tyriozela. Our results provide strong support for five major Heliozelidae clades: (i) a large widespread clade containing the leaf-mining genera Antispilina, Coptodisca and Holocacista and some species of Antispila, (ii) a clade containing most of the described Antispila, (iii) a clade containing the leaf-mining genus Heliozela and the monotypic genus Tyriozela, (iv) an Australian clade containing Pseliastis and (v) an Australian clade containing Hoplophanes. Each clade includes several new species and potentially new genera. Collectively, our data uncover a rich and undescribed diversity that appears to be especially prevalent in Australia. Our work highlights the need for a major taxonomic revision of the family and for generating a robust molecular phylogeny using multi-gene approaches in order to resolve the relationships among clades.

Mitochondrial DNA markers reveal high genetic diversity and strong genetic differentiation in populations of Dendrolimus kikuchii Matsumura (Lepidoptera: Lasiocampidae)

Dendrolimus kikuchii Matsumura, 1927 is a serious forest pest causing great damage to coniferous trees in China. Despite its economic importance, the population genetics of this pest are poorly known. We used three mitochondrial genes (COI, COII and Cytb) to investigate the genetic diversity and genetic differentiation of 15 populations collected from the main distribution regions of D. kikuchii in China. Populations show high haplotype and nucleotide diversity. Haplotype network and phylogenetic analysis divides the populations into three major clades, the central and southeastern China (CC+SEC) clade, the eastern China (EC) clade, and the southwestern China (SWC) clade. Populations collected from adjacent localities share the same clade, which is consistent with the strong relationship of isolation by distance (r = 0.74824, P = 0.00001). AMOVA analysis indicated that the major portion of this molecular genetic variation is found among the three groups of CC+SEC, EC and SWC (61.26%). Of 105 pairwise FST comparisons, 93 show high genetic differentiation. Populations of Puer (PE), Yangshuo (YS) and Leishan (LS) are separated from other populations by a larger genetic distance. Distributions of pairwise differences obtained with single and combined gene data from the overall populations are multimodal, suggesting these populations had no prior population expansion in southern China. The nonsignificant neutral test on the basis of Tajima' D and Fu's Fs, and the lack of a star-shaped haplotype network together with the multiple haplotypes support this hypothesis. Pleistocene climatic fluctuations, combined with the host specificity to Pinus species, made these regions of south China into a refuge for D. kikuchii. The high level of population genetic structuring is related to their weak flight capacity, their variations of life history and the geographic distance among populations.

Independent evolution of sexual dimorphism and female-limited mimicry in swallowtail butterflies (Papilio dardanus and Papilio phorcas)

Several species of swallowtail butterflies (genus Papilio) are Batesian mimics that express multiple mimetic female forms, while the males are monomorphic and nonmimetic. The evolution of such sex-limited mimicry may involve sexual dimorphism arising first and mimicry subsequently. Such a stepwise scenario through a nonmimetic, sexually dimorphic stage has been proposed for two closely related sexually dimorphic species: Papilio phorcas, a nonmimetic species with two female forms, and Papilio dardanus, a female-limited polymorphic mimetic species. Their close relationship indicates that female-limited polymorphism could be a shared derived character of the two species. Here, we present a phylogenomic analysis of the dardanus group using 3964 nuclear loci and whole mitochondrial genomes, showing that they are not sister species and thus that the sexually dimorphic state has arisen independently in the two species. Nonhomology of the female polymorphism in both species is supported by population genetic analysis of engrailed, the presumed mimicry switch locus in P. dardanus. McDonald-Kreitman tests performed on SNPs in engrailed showed the signature of balancing selection in a polymorphic population of P. dardanus, but not in monomorphic populations, nor in the nonmimetic P. phorcas. Hence, the wing polymorphism does not balance polymorphisms in engrailed in P. phorcas. Equally, unlike in P. dardanus, none of the SNPs in P. phorcas engrailed were associated with either female morph. We conclude that sexual dimorphism due to female polymorphism evolved independently in both species from monomorphic, nonmimetic states. While sexual selection may drive male-female dimorphism in nonmimetic species, in mimetic Papilios, natural selection for protection from predators in females is an alternative route to sexual dimorphism.

Tsukiyamaia, a new genus of the tribe Baorini (Lepidoptera, Hesperiidae, Hesperiinae)

Skippers of the tribe Baorini are evidently a monophyletic group in the subfamily Hesperiinae. In this study, a new Baorini member Tsukiyamaia albimacula gen. n. et sp. n. is described from north Myanmar, southwest China and north Vietnam. Despite its peculiar and striking wing-pattern, this new genus has some important characters of Baorini, such as a broad and bifid uncus and a well-developed gnathos. Based on an analysis of male genitalia and the molecular phylogenies inferred from both mitochondrial and nuclear genes (28 taxa, total aligned length: 2968 bp), it is proposed that the genus Tsukiyamaia is closely related to the genus Polytremis, which has high species diversity in China. This study not only describes a new skipper but also highlights that Tsukiyamaia is important in clarifying phylogenetic relationship of Polytremis and its allies.

Taxonomic interpretation of chromosomal and mitochondrial DNA variability in the species complex close to Polyommatus (Agrodiaetus) dama (Lepidoptera, Lycaenidae)

In this paper, by using combination of molecular and chromosomal markers, populations of Polyommatus (Agrodiaetus) karindus (Riley, 1921) from north-west and central Iran are analyzed. It has been found that taxon usually identified as Polyommatus (Agrodiaetus) karindus is represented in Iran by two geographically separated groups of individuals, strongly differentiated by their karyotypes and mitochondrial haplotypes. It is demonstrated that populations from NW Iran have the haploid chromosome number n = 68, while the haploid chromosome number of Polyommatus (Agrodiaetus) karindus from central Iran is found to be n = 73. Phylogenetic analysis revealed that these groups also differ by at least eight nucleotide substitutions in a 690 bp fragment of the mitochondrial COI gene and form separated groups of clusters in Bayesian inference tree. Thus, population entities from central Iran are described here as a new subspecies Polyommatus (Agrodiaetus) karindus saravandi ssp. n. Strong chromosomal and molecular differentiation are confirmed between Polyommatus (Agrodiaetus) karindus and its sister species, Polyommatus (Agrodiaetus) dama (Staudinger, 1892).

Repeated Reticulate Evolution in North American Papilio machaon Group Swallowtail Butterflies

Hybridization between distinct populations or species is increasingly recognized as an important process for generating biodiversity. However, the interaction between hybridization and speciation is complex, and the diverse evolutionary outcomes of hybridization are difficult to differentiate. Here we characterize potential hybridization in a species group of swallowtail butterflies using microsatellites, DNA sequences, and morphology, and assess whether adaptive introgression or homoploid hybrid speciation was the primary process leading to each putative hybrid lineage. Four geographically separated hybrid populations were identified in the Papilio machaon species group. One distinct mitochondrial DNA clade from P. machaon was fixed in three hybrid taxa (P. brevicauda, P. joanae, and P. m. kahli), while one hybrid swarm (P. zelicaon x machaon) exhibited this hybrid mtDNA clade as well as widespread parental mtDNA haplotypes from both parental species. Microsatellite markers and morphology showed variable admixture and intermediacy, ranging from signatures of prolonged differential introgression from the paternal species (P. polyxenes/P. zelicaon) to current gene flow with both parental species. Divergences of the hybrid lineages dated to early- to mid-Pleistocene, suggesting that repeated glaciations and subsequent range shifts of parental species, particularly P. machaon hudsonianus, facilitated initial hybridization. Although each lineage is distinct, P. joanae is the only taxon with sufficient evidence (ecological separation from parental species) to define it as a homoploid hybrid species. The repetition of hybridization in this group provides a valuable foundation for future research on hybridization, and these results emphasize the potential for hybridization to drive speciation in diverse ways.

Phylogeny and Historical Biogeography of Asian Pterourus Butterflies (Lepidoptera: Papilionidae): A Case of Intercontinental Dispersal from North America to East Asia

The phylogenetic status of the well-known Asian butterflies often known as Agehana (a species group, often treated as a genus or a subgenus, within Papilio sensu lato) has long remained unresolved. Only two species are included, and one of them especially, Papilio maraho, is not only rare but near-threatened, being monophagous on its vulnerable hostplant, Sassafras randaiense (Lauraceae). Although the natural history and population conservation of "Agehana" has received much attention, the biogeographic origin of this group still remains enigmatic. To clarify these two questions, a total of 86 species representatives within Papilionidae were sampled, and four genes (concatenated length 3842 bp) were used to reconstruct their phylogenetic relationships and historical scenarios. Surprisingly, "Agehana" fell within the American Papilio subgenus Pterourus and not as previously suggested, phylogenetically close to the Asian Papilio subgenus Chilasa. We therefore formally synonymize Agehana with Pterourus. Dating and biogeographic analysis allow us to infer an intercontinental dispersal of an American ancestor of Asian Pterourus in the early Miocene, which was coincident with historical paleo-land bridge connections, resulting in the present "East Asia-America" disjunction distribution. We emphasize that species exchange between East Asia and America seems to be a quite frequent occurrence in butterflies during the Oligocene to Miocene climatic optima.

The complete mitochondrial genome of Papilio glaucus and its phylogenetic implications

Due to the intriguing morphology, lifecycle, and diversity of butterflies and moths, Lepidoptera are emerging as model organisms for the study of genetics, evolution and speciation. The progress of these studies relies on decoding Lepidoptera genomes, both nuclear and mitochondrial. Here we describe a protocol to obtain mitogenomes from Next Generation Sequencing reads performed for whole-genome sequencing and report the complete mitogenome of Papilio (Pterourus) glaucus. The circular mitogenome is 15,306 bp in length and rich in A and T. It contains 13 protein-coding genes (PCGs), 22 transfer-RNA-coding genes (tRNA), and 2 ribosomal-RNA-coding genes (rRNA), with a gene order typical for mitogenomes of Lepidoptera. We performed phylogenetic analyses based on PCG and RNA-coding genes or protein sequences using Bayesian Inference and Maximum Likelihood methods. The phylogenetic trees consistently show that among species with available mitogenomes Papilio glaucus is the closest to Papilio (Agehana) maraho from Asia.

Genetic evaluation of the evolutionary distinctness of a federally endangered butterfly, Lange's Metalmark

Background

The Mormon Metalmark (Apodemia mormo) species complex occurs as isolated and phenotypically variable colonies in dryland areas across western North America. Lange’s Metalmark, A. m. langei, one of the 17 subspecies taxonomically recognized in the complex, is federally listed under the U.S. Endangered Species Act of 1973. Metalmark taxa have traditionally been described based on phenotypic and ecological characteristics, and it is unknown how well this nomenclature reflects their genetic and evolutionary distinctiveness. Genetic variation in six microsatellite loci and mitochondrial cytochrome oxidase subunit I sequence was used to assess the population structure of the A. mormo species complex across 69 localities, and to evaluate A. m. langei’s qualifications as an Evolutionarily Significant Unit.

Results

We discovered substantial genetic divergence within the species complex, especially across the Continental Divide, with population genetic structure corresponding more closely with geographic proximity and local isolation than with taxonomic divisions originally based on wing color and pattern characters. Lange’s Metalmark was as genetically divergent as several other locally isolated populations in California, and even the unique phenotype that warranted subspecific and conservation status is reminiscent of the morphological variation found in some other populations.

Conclusions

This study is the first genetic treatment of the A. mormo complex across western North America and potentially provides a foundation for reassessing the taxonomy of the group. Furthermore, these results illustrate the utility of molecular markers to aid in demarcation of biological units below the species level. From a conservation point of view, Apodemia mormo langei’s diagnostic taxonomic characteristics may, by themselves, not support its evolutionary significance, which has implications for its formal listing as an Endangered Species.

Electronic supplementary material

The online version of this article (doi:10.1186/s12862-015-0354-9) contains supplementary material, which is available to authorized users.

Morphological characters are compatible with mitogenomic data in resolving the phylogeny of nymphalid butterflies (lepidoptera: papilionoidea: nymphalidae)

Nymphalidae is the largest family of butterflies with their phylogenetic relationships not adequately approached to date. The mitochondrial genomes (mitogenomes) of 11 new nymphalid species were reported and a comparative mitogenomic analysis was conducted together with other 22 available nymphalid mitogenomes. A phylogenetic analysis of the 33 species from all 13 currently recognized nymphalid subfamilies was done based on the mitogenomic data set with three Lycaenidae species as the outgroups. The mitogenome comparison showed that the eleven new mitogenomes were similar with those of other butterflies in gene content and order. The reconstructed phylogenetic trees reveal that the nymphalids are made up of five major clades (the nymphaline, heliconiine, satyrine, danaine and libytheine clades), with sister relationship between subfamilies Cyrestinae and Biblidinae, and most likely between subfamilies Morphinae and Satyrinae. This whole mitogenome-based phylogeny is generally congruent with those of former studies based on nuclear-gene and mitogenomic analyses, but differs considerably from the result of morphological cladistic analysis, such as the basal position of Libytheinae in morpho-phylogeny is not confirmed in molecular studies. However, we found that the mitogenomic phylogeny established herein is compatible with selected morphological characters (including developmental and adult morpho-characters).

Phylogenetic utility of ribosomal genes for reconstructing the phylogeny of five Chinese satyrine tribes (Lepidoptera, Nymphalidae)

Satyrinae is one of twelve subfamilies of the butterfly family Nymphalidae, which currently includes nine tribes. However, phylogenetic relationships among them remain largely unresolved, though different researches have been conducted based on both morphological and molecular data. However, ribosomal genes have never been used in tribe level phylogenetic analyses of Satyrinae. In this study we investigate for the first time the phylogenetic relationships among the tribes Elymniini, Amathusiini, Zetherini and Melanitini which are indicated to be a monophyletic group, and the Satyrini, using two ribosomal genes (28s rDNA and 16s rDNA) and four protein-coding genes (EF-1α, COI, COII and Cytb). We mainly aim to assess the phylogenetic informativeness of the ribosomal genes as well as clarify the relationships among different tribes. Our results show the two ribosomal genes generally have the same high phylogenetic informativeness compared with EF-1α; and we infer the 28s rDNA would show better informativeness if the 28s rDNA sequence data for each sampling taxon are obtained in this study. The placement of the monotypic genus Callarge Leech in Zetherini is confirmed for the first time based on molecular evidence. In addition, our maximum likelihood (ML) and Bayesian inference (BI) trees consistently show that the involved Satyrinae including the Amathusiini is monophyletic with high support values. Although the relationships among the five tribes are identical among ML and BI analyses and are mostly strongly-supported in BI analysis, those in ML analysis are lowly- or moderately- supported. Therefore, the relationships among the related five tribes recovered herein need further verification based on more sampling taxa.

Genetic Diversity and Structure of Brazilian Populations of Diatraea saccharalis (Lepidoptera: Crambidae): Implications for Pest Management

The sugarcane borer, Diatraea saccharalis (F.), is the main pest of sugarcane in Brazil. Genetic variability and gene flow among 13 Brazilian populations of the species were evaluated based on mitochondrial DNA sequences to estimate the exchange of genetic information within and among populations. We found high genetic structure among sampled localities (ΦST=0.50923), and pairwise genetic distances were significantly correlated to geographic distances. Demographic analysis and genealogical network of mitochondrial sequences indicate population growth and admixture of D. saccharalis populations, events likely related to the sequential expansion of the corn and sugarcane crops in Brazil. The implications of these findings for pest management are discussed.

A new Heraclides swallowtail (Lepidoptera, Papilionidae) from North America is recognized by the pattern on its neck

Heraclidesrumiko Shiraiwa & Grishin, sp. n. is described from southwestern United States, Mexico, and Central America (type locality: USA, Texas, Duval County). It is closely allied to Heraclidescresphontes (Cramer, 1777) and the two species are sympatric in central Texas. The new species is diagnosed by male genitalia and exhibits a nearly 3% difference from Heraclidescresphontes in the COI DNA barcode sequence of mitochondrial DNA. The two Heraclides species can usually be told apart by the shape and size of yellow spots on the neck, by the wing shape, and the details of wing patterns. "Western Giant Swallowtail" is proposed as the English name for Heraclidesrumiko. To stabilize nomenclature, neotype for Papiliocresphontes Cramer, 1777, an eastern United States species, is designated from Brooklyn, New York, USA; and lectotype for Papiliothoas Linnaeus, 1771 is designated from Suriname. We sequenced DNA barcodes and ID tags of nearly 400 Papilionini specimens completing coverage of all Heraclides species. Comparative analyses of DNA barcodes, genitalia, and facies suggest that Heraclidesoviedo (Gundlach, 1866), reinstated status, is a species-level taxon rather than a subspecies of Heraclidesthoas (Linnaeus, 1771); and Heraclidespallas (G. Gray, [1853]), reinstated status, with its subspecies HeraclidesPapiliobajaensis (J. Brown & Faulkner, 1992), comb. n., and Heraclidesanchicayaensis Constantino, Le Crom & Salazar, 2002, stat. n., are not conspecific with Heraclidesastyalus (Godart, 1819).

The evolutionary genetics of highly divergent alleles of the mimicry locus in Papilio dardanus

BACKGROUND

The phylogenetic history of genes underlying phenotypic diversity can offer insight into the evolutionary origin of adaptive traits. This is especially true where single genes have large phenotypic effects, for example in determining polymorphic mimicry in butterflies. Here, we characterise the evolutionary history of two candidate genes for the mimicry switch in the polymorphic Batesian mimic Papilio dardanus coding for the transcription factors engrailed and invected.

RESULTS

We show that phased haplotypes associated with the dominant morphs f. poultoni and f. planemoides are phylogenetically highly divergent, in particular at non-synonymous sites. Some non-synonymous changes are shared between the divergent alleles suggesting either convergence or a shared ancestry. Gene trees for invected do not show this pattern. Despite their great divergence, all engrailed alleles of P. dardanus were monophyletic with respect to alleles of closely related species. Phylogenetic analyses therefore reveal no evidence for introgression from other species. A McDonald-Kreitman test conducted on a population sample from South Africa confirms a significant excess of intraspecific non-synonymous diversity in P. dardanus engrailed, suggesting long-term balanced polymorphism at this locus.

CONCLUSIONS

The divergence between engrailed haplotypes suggests an evolutionary history distorted by selection with multiple changes reflecting recurrent selective sweeps. The high level of intraspecific polymorphism observed is characteristic of balancing selection on this locus, as expected if the gene engrailed is under phenotypic selection for the maintenance of multiple mimetic morphs. Non-synonymous changes in key functional portions of a major transcription factor are likely to be deleterious but if maintained in a dominant allele at low frequency, heterozygosity would reduce the associated genetic load.

Neotropical Monogenoidea. 58. Three new species of Gyrodactylus (Gyrodactylidae) from Scleromystax spp. (Callichthyidae) and the proposal of COII gene as an additional fragment for barcoding gyrodactylids

Based on molecular markers (COII and ITS1-ITS2) and morphological data, we describe three new Neotropical species of Gyrodactylus von Nordmann, 1832 from Scleromystax barbatus (Quoy et Gaimard) and Scleromystax macropterus (Regan) from southern Brazil. The three new species can be distinguished from each other by sequences of both molecular markers and morphology of hooks and anchors. Gyrodactylus bueni sp. n. is characterised by having hook with shaft curved, heel straight, shelf straight, toe pointed, anchor with superficial root slender, elongate and male copulatory organ armed with two rows of spinelets. Gyrodactylus major sp. n. presents hook with shaft, point curved, proximal shaft straight, heel convex, shelf convex, toe concave, anchor with superficial root robust and male copulatory organ armed with two rows of spinelets. Gyrodactylus scleromystaci sp. n. presents hook with shaft, point recurved, heel convex, shelf convex, toe pointed, anchor with superficial root curved and male copulatory organ armed with two rows of spinelets. These species appear to be closely related to other species of Gyrodactylus known from other species of Callichthyidae. These new species, however, differ by the comparative morphology of the haptoral hard structures and molecular data. Comparative analysis of sequences from these species of Gyrodactylus suggests that the COII gene may represent an important marker for the taxonomy of species of Gyrodactylidae and, perhaps, for species of other lineages of Monogenoidea.

Wolbachia infection status and genetic structure in natural populations of Polytremis nascens (Lepidoptera: Hesperiidae)

The maternally inherited obligate bacteria Wolbachia is known for infecting the reproductive tissues of a wide range of arthropods. In this study, we surveyed Wolbachia infections in Polytremis nascens (Lepidoptera: Hesperiidae) from 14 locations in China by amplifying the 16S rRNA gene with a nested PCR method and revealed the effect of Wolbachia on host mitochondrial DNA. The results show that 31% (21/67) are Wolbachia positive among all specimens and mainly prevails in southern populations in China. No significant difference in the prevalence is found between the sexes. Notably, the nucleotide diversity of Wolbachia infected butterflies is smaller compared to that of uninfected butterflies. The mitochondrial DNA of infected group appear to be not evolving neutrally (Tajima's D value=-2.3303 and Fu's F values=-3.7068). The analysis of molecular variance shows significant differentiation of mitochondrial haplotypes between infected and uninfected specimens (FST=0.6064). The mismatch analysis speculated the different expansion pattern in Wolbachia infected specimens and all P. nascens specimens. These results suggest that the populations of P. nascens may have recently been subjected to a Wolbachia-induced sweep. Additionally, phylogenetic analysis differentiated the mitochondrial haplotypes of P. nascens into three major clades. The clades are in perfect agreement with the pattern of Wolbachia infection. One of the clades grouped with the butterflies infected with Wolbachia. The remaining two clades grouped with uninfected butterflies from the central-west of China populations and Eastern and Southern China populations respectively, which are isolated mainly by the Yangtze River. The analysis of haplotype networks, geographic distribution and population size change shows that Haplotype 1 in central-west of China is the ancestral haplotype and the populations of P. nascens are expanded.

Molecular systematics of the Simulium jenningsi species group (Diptera: Simuliidae), with three new fast-evolving nuclear genes for phylogenetic inference

A molecular phylogeny was inferred for the 22 nominal species of black flies in the Simulium jenningsi species group, which includes major pests of humans and livestock in North America. Females are structurally monomorphic, presenting a problem for identification of the pests. For each species, we sequenced approximately two kilobases from the mitochondrial genome (ND2, Cox I, proximal one-half of Cox II) and about six kilobases from the nuclear genome (ca. 2 kilobases each from 3 rapidly evolving nuclear genes: big zinc finger [BZF], "5-intron gene" [5intG], and elongation complex protein 1 [ECP1]) and analyzed them phylogenetically using maximum likelihood and Bayesian methods. The three nuclear loci have not previously been used in phylogenetic studies. The mitochondrial region recovered 6 group members as monophyletic. BZF, 5intG, and ECP1 sequences each permitted identification of 13 species and recovered the S. fibrinflatum and S. taxodium subgroups. Simulium aranti Stone and Snoddy and S. luggeri Nicholson and Mickel were consistently recovered at the base of the group. Simulium ozarkense Moulton and Adler, S. dixiense Stone and Snoddy, S. krebsorum Moulton and Adler, and S. haysi Stone and Snoddy branched off before two well-supported sister groups of the remaining species. This remainder consisted of species occupying slow, sandy lowland streams-S. definitum Moulton and Adler, S. jonesi Stone and Snoddy, and the S. taxodium subgroup (S. taxodium Snoddy and Beshear, S. chlorum Moulton and Adler, S. confusum Moulton and Adler, and S. lakei Snoddy)-as sister to two clades of species inhabiting swift, rocky upland streams-the S. fibrinflatum subgroup (S. fibrinflatum Twinn, S. notiale Stone and Snoddy, and S. snowi Stone and Snoddy) and a clade comprised of S. anchistinum Moulton and Adler, S. jenningsi Malloch, and S. nyssa Stone and Snoddy, plus species having cocoons without anterolateral apertures (S. infenestrum Moulton and Adler, S. podostemi Snoddy, S. penobscotense Snoddy and Bauer, and S. remissum Moulton and Adler). Simulium snowi Stone and Snoddy is here considered a synonym of S. notiale Stone and Snoddy. Trees inferred from BZF and 5intG were largely concordant with those from ECP1, but slightly less resolved. Combining mitochondrial and nuclear data sets did not greatly improve the performance of the ECP1 data set alone. We, therefore, propose ECP1 as the gold standard for identification of members of the S. jenningsi group. Maximum likelihood analysis of combined sequences from all three nuclear genes, with three morphological constraints imposed, yielded a tree proposed as the best hypothesis of relationships among group members, based on all available data.

The complete chloroplast genome sequence of Mahonia bealei (Berberidaceae) reveals a significant expansion of the inverted repeat and phylogenetic relationship with other angiosperms

Mahonia bealei (Berberidaceae) is a frequently-used traditional Chinese medicinal plant with efficient anti-inflammatory ability. This plant is one of the sources of berberine, a new cholesterol-lowering drug with anti-diabetic activity. We have sequenced the complete nucleotide sequence of the chloroplast (cp) genome of M. bealei. The complete cp genome of M. bealei is 164,792 bp in length, and has a typical structure with large (LSC 73,052 bp) and small (SSC 18,591 bp) single-copy regions separated by a pair of inverted repeats (IRs 36,501 bp) of large size. The Mahonia cp genome contains 111 unique genes and 39 genes are duplicated in the IR regions. The gene order and content of M. bealei are almost unarranged which is consistent with the hypothesis that large IRs stabilize cp genome and reduce gene loss-and-gain probabilities during evolutionary process. A large IR expansion of over 12 kb has occurred in M. bealei, 15 genes (rps19, rpl22, rps3, rpl16, rpl14, rps8, infA, rpl36, rps11, petD, petB, psbH, psbN, psbT and psbB) have expanded to have an additional copy in the IRs. The IR expansion rearrangement occurred via a double-strand DNA break and subsequence repair, which is different from the ordinary gene conversion mechanism. Repeat analysis identified 39 direct/inverted repeats 30 bp or longer with a sequence identity ≥ 90%. Analysis also revealed 75 simple sequence repeat (SSR) loci and almost all are composed of A or T, contributing to a distinct bias in base composition. Comparison of protein-coding sequences with ESTs reveals 9 putative RNA edits and 5 of them resulted in non-synonymous modifications in rpoC1, rps2, rps19 and ycf1. Phylogenetic analysis using maximum parsimony (MP) and maximum likelihood (ML) was performed on a dataset composed of 65 protein-coding genes from 25 taxa, which yields an identical tree topology as previous plastid-based trees, and provides strong support for the sister relationship between Ranunculaceae and Berberidaceae. Molecular dating analyses suggest that Ranunculaceae and Berberidaceae diverged between 90 and 84 mya, which is congruent with the fossil records and with recent estimates of the divergence time of these two taxa.

Ancestral gene organization in the mitochondrial genome of Thyridosmylus langii (McLachlan, 1870) (Neuroptera: Osmylidae) and implications for lacewing evolution

The first complete mitochondrial genome of the lacewing family Osmylidae (Thyridosmylus langii (McLachlan, 1870)) (Neuroptera) was sequenced in this study. The genome is a circular molecule of 16,221 bp containing the typical 37 genes but is arranged in the same order as that of the putative ancestor of hexapod and lacks translocation of trnC as shared by all previously sequenced neuropteran mtDNAs. This reveals that trnC translocation does not represent an organizational synapomorphy in the mitochondrion for the entire Neuroptera clade. Comparative analysis of neuropteran tRNA genes reveals a relatively slow and conserved evolution of the mitochondrion throughout the order. Secondary structure models of the ribosomal RNA genes of T. langii largely agree with those proposed for other insect orders. Nevertheless, domain I of T. langii rrnL is consisted of nine helices rather than eight helices which is typical for neuropteran rrnL. Protein-coding genes have typical mitochondrial start codons, with the exception of COI, which uses the TCG start codon also found in Ithonidae and Chrysopidae. Like other neuropteran insects, the control region is the most AT-rich region and comparatively simple, with little evidence of conserved blocks or long tandem repeats. Considering the issues of base-compositional and branch length heterogeneity, we used a range of phylogenetic approaches to recover neuropteridan relationships and explored the effect of method choice on recovery of monophyly of Neuropterida: ((Neuroptera + Megaloptera) + Raphidioptera). The monophyly of Neuroptera and the more basal position of Osmylidae were also recovered by different datasets and phylogenetic methods.

A new Brazilian Passiflora leafminer: Spinivalva gaucha, gen. n., sp. n. (Lepidoptera, Gracillariidae, Gracillariinae), the first gracillariid without a sap-feeding instar

Male, female, pupa, larva and egg of a new genus and species of Gracillariidae (Gracillariinae), Spinivalva gaucha Moreira and Vargas from southern Brazil are described and illustrated with the aid of optical and scanning electron microscopy. A preliminary analysis of mitochondrial DNA sequences including members of related lineages is also provided. The immature stages are associated with Passiflora actinia, Passiflora misera and Passiflora suberosa (Passifloraceae), and build mines on the adaxial leaf surface. Initially the mines are serpentine in shape, but later in larval ontogeny become a blotch type. Although the larvae are hypermetamorphic as in other Gracillariidae, there is no sap-feeding instar in Spinivalva gaucha; the larva feeds on the palisade parenchyma, thus producing granular frass during all instars. Pupation occurs outside the mine; prior to pupating, the larva excretes numerous bubbles that are placed in rows on the lateral margins of the cocoon external surface. This is the second genus of gracillariid moth described for the Atlantic Rain Forest, and the second gracillariid species known to be associated with Passifloraceae.

Complete mitochondrial genome of the Common Evening Brown, Melanitis leda Linnaeus (Lepidoptera: Nymphalidae: Satyrinae)

The complete mitochondrial genome (mitogenome) of Melanitis leda (Lepidoptera: Nymphalidae: Satyrinae) is a circular molecule of 15,122 bp in length, containing 37 typical animal mitochondrial genes and 1 control region, known in insects as the AT-rich region. Its gene content and order are identical to all other available butterfly mitogenomes. All protein-coding genes (PCGs) start with a typical ATN initiation codon, except for COI, which is initiated by the CGA codon as observed in other butterfly species. A total of 97 bp of intergenic spacers are interspersed in 11 regions, ranging in size from 1 to 45 bp. The 314-bp-long AT-rich region is the smallest of all the butterfly corresponding regions available and contains some conserved structures similar to those found in other butterfly mitogenomes, including the motif ATAGA followed by a 19-bp poly-T stretch and a microsatellite-like (AT)6 element preceded by the ATTTA motif.

Complete Mitogenomes of Euploea mulciber (Nymphalidae: Danainae) and Libythea celtis (Nymphalidae: Libytheinae) and Their Phylogenetic Implications

The complete mitochondrial genome sequences of the two butterfly species Euploea mulciber (Lepidoptera: Nymphalidae: Danainae) and Libythea celtis (Lepidoptera: Nymphalidae: Libytheinae) were determined in this study, comprising 15,166 bp and 15,164 bp, respectively. The orientation and the gene order of the two mitogenomes are identical to those of most of the other lepidopteran species. All protein-coding genes of Euploea mulciber and Libythea celtis mitogenomes start with a typical ATN codon with the exception of COI gene which uses CGA as its initial codon. All tRNA genes possess the typical cloverleaf secondary structure except for tRNASer (AGN), which has a simple loop with the absence of the DHU stem. There are short microsatellite-like repeat regions, but no conspicuous macrorepeats scattered throughout the A + T-rich regions. Phylogenetic analysis among the available butterfly species suggests that Libythea celtis (Libytheinae) is closely related to Calinaga davidis (Calinaginae), indicating that the subfamily Libytheinae may not represent a basal lineage of the Nymphalidae as previously suggested, and that Euploea mulciber stands at the base of the nymphalid tree as a sister to all other nymphalids.

Unprecedented ichneumonid parasitoid wasp diversity in tropical forests

The megadiverse parasitoid wasp family Ichneumonidae (Hymenoptera) is classically considered an exception to the extensively studied latitudinal diversity gradient: the majority of ichneumonid species are described from temperate regions. The gradient has been hypothesized to be dependent on the biology of the wasps, but recently questions of sampling and description biases have been raised. Here, we show with primary data that the species richness of Ichneumonidae is markedly underestimated in tropical areas and that latitudinal diversity patterns in the family remain uncharacterized. We discovered a startling 177 likely undescribed orthocentrine species with relatively low sampling effort in the forests of Central America and Amazonian Ecuador, over three times the previously known orthocentrine diversity in the world's tropics. Species accumulation curves reveal that we are just beginning to unveil the true extent of tropical orthocentrine diversity. We also found evidence for cryptic species; our DNA analysis revealed additional species not easily distinguishable using morphological characteristics. The difficulty in establishing species richness patterns of Ichneumonidae probably follows from the relative lack of taxonomic expertise and the low density of ichneumonid species throughout the landscape.

Diffuse coevolution between two Epicephala species (Gracillariidae) and two Breynia species (Phyllanthaceae)

The diffuse coevolution between two moth species (Epicephala lativalvaris and E. mirivalvata) and two plant species (Breynia fruticosa and B. rostrata) is reported based on field observations and indoor experiments conducted in Hainan and Fujian, China. Study results showed that the two Epicephala species jointly pollinated the two Breynia species, which led to a unique obligate pollination mutualism of two-to-two species specificity. A single Epicephala larva exclusively fed on seeds of host plants and developed to maturity by consuming all six seeds of each fruit, whereas a fraction of intact fruits were left to ensure the reproduction of plants within the whole population. Larvae of the two Epicephala species are competitive for resources; the population of E. mirivalvata is much smaller than that of E. lativalvaris, which has resulted from the differences in the female ovipositor structures and oviposition mode. The life history of Epicephala species highly coincides with the phenology of Breynia plants, and different phenology of B. fruticosa resulted in the different life history of the two Epicephala species in Hainan and Fujian. The natural hybridization of two host plants, possibly induced by the alternate pollination of two Epicephala species, is briefly discussed.