Phylogenetic relationships among superfamilies of Cicadomorpha (Hemiptera: Auchenorrhyncha) inferred from the wing base structure

The infraorder Cicadomorpha is a monophyletic group of the order Hemiptera, suborder Auchenorrhyncha, and is composed of three superfamilies: Cercopoidea (spittle bugs), Cicadoidea (cicadas) and Membracoidea (leafhoppers and treehoppers). Phylogenetic relationships among the superfamilies have been highly controversial morphologically and molecularly, but recent molecular phylogenetic analyses provided support for Cercopoidea + Cicadoidea. In this study, we examined morphology of the wing base structure in Cicadomorpha and tested the previous phylogenetic hypotheses using the characters selected from the wing base. As a result, a sister‐group relationship between Cicadoidea and Cercopoidea was supported by three synapomorphies (presence of a projection posterior to the anterior notal wing process, presence of a novel notal process anterior to the posterior notal wing process, presence of a novel sclerite between the distal median plate and the base of anal vein). The present study provides the first unambiguous and prominent morphological support for Cicadoidea + Cercopoidea.     

Molecular phylogeny of Cicadomorpha (Insecta: Hemiptera: Cicadoidea, Cercopoidea and Membracoidea): adding evidence to the controversy

Abstract. The hemipteran infraorder Cicadomorpha comprises the superfamilies Cicadoidea (cicadas), Cercopoidea (spittlebugs or froghoppers) and Membracoidea (leafhoppers and treehoppers). Earlier attempts to determine relationships among these three monophyletic lineages using either morphological or molecular data suffered from insufficient sampling (taxonomic and data) and problematic tree rooting, leading to discordant results. Presented here are phylogenetic reconstructions within Cicadomorpha based on DNA nucleotide sequence data from multiple genetic markers (18S rDNA, 28S rDNA, and histone 3) sequenced from representative taxa of Cicadidae, Tettigarctidae, Cercopidae, Aphrophoridae, Clastopteridae, Machaerotidae, Epipygidae, Cicadellidae, Membracidae, Myerslopiidae and Aetalionidae. To test the robustness of the phylogenetic signal, these sequence data were analysed separately and in combination under various alignment parameters using both manual alignment (of both attenuated and full sequences) and alignment via clustal x . The results demonstrate clearly that, despite the alignment method used, basing a phylogeny on a single gene region is often misleading. Analyses of the combination of datasets support the major relationships within Cicadomorpha as (Membracoidea (Cicadoidea, Cercopoidea)). Internal relationships recovered within each superfamily shows evidence for: (1) the placement of Myerslopiidae as the sister group of the remaining Membracoidea; (2) the paraphyly of Cicadellidae; (3) the sister-group relationship between Machaerotidae and Clastopteridae; (4) the monophyly of Cercopidae; (5) the diversification of Epipygidae from within the possibly paraphyletic Aphrophoridae.     

Superfamily Membracoidea (Homoptera: Auchenorrhyncha). II. Cladistic analysis and conclusions

Abstract. Homologies among traditional morphological characters in the Membracoidea ( sensu lato ) are reassessed and the phylogenetic relationships among higher membracoid taxa are explored, incorporating new morphological evidence from nymphs and adults. Weighted and unweighted parsimony analyses of a matrix of sixty–three characters and thirty-nine OTUs representing the families Aetalionidae, Cicadellidae, Melizoderidae and Membracidae, and an outgroup (superfamily Cercopoidea) yielded various topologies that were largely congruent but presented alternative hypotheses of relationships among the Membracidae. These analyses indicate that the superfamily consists of the following clades: Cicadellidae + (Melizoderidae + (Aetalionidae + Membracidae)). The family Membracidae, traditionally characterized by the presence of a posterior pronotal process, apparently gave rise to Nicomia Stål and other genera that lack this process.     

Two ancient bacterial endosymbionts have coevolved with the planthoppers (Insecta: Hemiptera: Fulgoroidea)

ABSTRACT: BACKGROUND: Members of the hemipteran suborder Auchenorrhyncha (commonly known as planthoppers, tree- and leafhoppers, spittlebugs, and cicadas) are unusual among insects known to harbor endosymbiotic bacteria in that they are associated with diverse assemblages of bacterial endosymbionts. Early light microscopic surveys of species representing the two major lineages of Auchenorrhyncha (the planthopper superfamily Fulgoroidea; and Cicadomorpha, comprising Membracoidea [tree- and leafhoppers], Cercopoidea [spittlebugs], and Cicadoidea [cicadas]), found that most examined species harbored at least two morphologically distinct bacterial endosymbionts, and some harbored as many as six. Recent investigations using molecular techniques have identified multiple obligate bacterial endosymbionts in Cicadomorpha; however, much less is known about endosymbionts of Fulgoroidea. In this study, we present the initial findings of an ongoing PCR-based survey (sequencing 16S rDNA) of planthopper-associated bacteria to document endosymbionts with a long-term history of codiversification with their fulgoroid hosts. RESULTS: Results of PCR surveys and phylogenetic analyses of 16S rDNA recovered a monophyletic clade of Betaproteobacteria associated with planthoppers; this clade included Vidania fulgoroideae, a recently described bacterium identified in exemplars of the planthopper family Cixiidae. We surveyed 77 planthopper species representing 18 fulgoroid families, and detected Vidania in 40 species (representing 13 families). Further, we detected the Sulcia endosymbiont (identified as an obligate endosymbiont of Auchenorrhyncha in previous studies) in 30 of the 40 species harboring Vidania. Concordance of the Vidania phylogeny with the phylogeny of the planthopper hosts (reconstructed based on sequence data from five genes generated from the same insect specimens from which the bacterial sequences were obtained) was supported by statistical tests of codiversification. Codiversification tests also supported concordance of the Sulcia phylogeny with the phylogeny of the planthopper hosts, as well as concordance of planthopper-associated Vidania and Sulcia phylogenies. CONCLUSIONS: Our results indicate that the Betaproteobacterium Vidania is an ancient endosymbiont that infected the common ancestor of Fulgoroidea at least 130 million years ago. Comparison of our findings with the early light-microscopic surveys conducted by Muller suggests that Vidania is Muller's x-symbiont, which he hypothesized to have codiversified with most lineages of planthoppers and with the Sulcia endosymbiont.     

Insights into chromosomal evolution of Cicadomorpha using fluorochrome staining and mapping 18S rRNA and H3 histone genes

The infraorder Cicadomorpha (Hemiptera) is a cosmopolitan species‐rich lineage of phytophagous insects. They have holocentric chromosomes and vary greatly in diploid number across families, with X0 as the predominant sex male mechanism. Here, we advance the understanding of chromosome mapping of repetitive elements of four families of cicadomorphan insects, the spittlebugs (Cercopidae), leafhoppers (Cicadellidae), and treehoppers (Aetalionidae and Membracidae). Sampled individuals from 19 species show considerable variation in diploid number, which may have originated from fusions between autosomes or between autosomes and the ancient X. The distribution of CMA₃⁺ blocks, primarily observed in low numbers in autosomal regions, was a conserved trait. Likewise, fluorescence in situ hybridization (FISH) mapping revealed mainly one locus per haploid genome for the 18S rRNA gene and for H3, each of which is located on distinct chromosomes. Despite the extensive variation in the number of autosomes and sex systems, the number of loci of ribosomal and H3 genes remained stable and may reflect the ancestral genome organizations in these groups. These results shed light on the chromosomal‐level organization in Cicadomorpha and provide new insights into the evolutionary history of karyotypes and repetitive elements in this diverse insect lineage.     

Does wing morphology affect recolonization of restored farmland by ground‐dwelling beetles?

Revegetation of previously cleared land is widely used to increase habitat area and connectivity of remnant vegetation for biodiversity conservation. Whether new habitat attracts or supports fauna depends on the dispersal traits of those fauna as well as the structure and composition of the surrounding landscape. Here, we examined wing morphology as a key dispersal trait for beetles in a revegetated landscape and asked, first, how it was related to phylogeny (family), trophic position, and body size. Second, we asked if wing morphology of recolonizing (or persisting) beetles varied with habitat characteristics at multiple scales, from microhabitat to landscape context. Third, we examined how common winged and wingless species responded to habitat at multiple scales. We measured the wing morphology of ground‐dwelling beetles from a restoration chronosequence, including paddocks, “young” revegetation (8–11 years old), “old” revegetation (14–19 years old), and fenced remnant vegetation. We found that body size and family membership were significant predictors of winglessness, with wingless species of carabids and curculionids being larger than their winged counterparts. We found no difference in the number of sites occupied by winged and wingless species, and no relationship between the wing morphology traits represented in different locations and habitat characteristics or landscape context. Furthermore, the most abundant species of both winged and wingless ground‐dwelling beetles had relatively little affinity to any habitat successional stage. Thus, despite intrinsic differences in wing morphology among species of ground‐dwelling beetle, we found no evidence that flight‐related dispersal limitations influenced recolonization (or persistence) in this landscape.     

Higher‐level phylogeny of the insect order Hemiptera: is Auchenorrhyncha really paraphyletic?

The higher‐level phylogeny of the order Hemiptera remains a contentious topic in insect systematics. The controversy is chiefly centred on the unresolved question of whether or not the hemipteran suborder Auchenorrhyncha (including the extant superfamilies Fulgoroidea, Membracoidea, Cicadoidea and Cercopoidea) is a monophyletic lineage. Presented here are the results of a multilocus molecular phylogenetic investigation of relationships among the major hemipteran lineages, designed specifically to address the question of Auchenorrhyncha monophyly in the context of broad taxonomic sampling across Hemiptera. Phylogenetic analyses (maximum parsimony, maximum likelihood and Bayesian inference) were based on DNA nucleotide sequence data from seven gene regions (18S rDNA, 28S rDNA, histone H3, histone 2A, wingless, cytochrome c oxidase I and NADH dehydrogenase subunit 4) generated from 86 in‐group exemplars representing all major lineages of Hemiptera (plus seven out‐group taxa). All combined analyses of these data recover the monophyly of Auchenorrhyncha, and also support the monophyly of each of the following lineages: Hemiptera, Sternorrhyncha, Heteropterodea, Heteroptera, Fulgoroidea, Cicadomorpha, Membracoidea, Cercopoidea and Cicadoidea. Also presented is a review of the major lines of morphological and molecular evidence for and against the monophyly of Auchenorrhyncha.     

十二种沫蝉的染色体研究 (同翅目： 沫蝉总科)

观察了同翅目头喙亚目12种沫蝉雄性的染色体数目和减数分裂行为。通过对沫蝉总科现有核型资料的分析,认为沫蝉总科的核型特点是：①染色体较小,数目较多,总科内染色体数目变化范围较大,众数为2n=26（24+XO）;②染色体的易位现象极为普遍,因此可以推测,通过染色体的易位导致染色体数目增加是核型进化的主要机制;③减数分裂前期Ⅰ具有典型的花束期,但没有弥散期。因此从精子发生来看沫蝉总科与叶蝉总科、角蝉总科和蝉总科的关系更为密切,而与蜡蝉总科的关系较远。头喙亚目的亲缘关系可能是：蜡蝉总科+{蝉总科+［沫蝉总科+（叶蝉总科+角蝉总科）］}。     

缅甸北部白垩纪中期克钦琥珀华翅蝉科(昆虫纲, 半翅目)新材料

根据产自缅甸北部白垩纪中期克钦琥珀中的一块昆虫化石标本,建立了1新种——克钦雅翅蝉(Ornatiala kachinensis sp. nov.),归于华翅蝉科(Sinoalidae Wang and Szwedo, 2012)。根据新化石材料,对雅翅蝉属的鉴别特征进行了修订。此外,利用支序分类学分析手段对新种的生物系统学地位进行了确定,并对华翅蝉前翅色型、翅脉变异等问题进行了探讨。新材料的发现进一步证实克钦琥珀生物群中的华翅蝉生物多样性程度较高,为优势昆虫类群。     

A revised interpretation of the wing base structure in Odonata

Abstract Homology of the wing base structure in the Odonata is highly controversial, and many different interpretations of homology have been proposed. In extreme cases, two independent origins of insect wings have been suggested, based on comparative morphology between the odonate and other pterygote wing bases. Difficulties in establishing homology of the wing base structures between Odonata and other Pterygota result mainly from their extreme differences in morphology and function. In the present paper, we establish homology of the wing base structures between Neoptera, Ephemeroptera and Odonata using highly conservative and unambiguously identifiable characters (the basal wing hinge and subcostal veins) as principal landmarks. Homology of the odonate wing base structure with those of Ephemeroptera and Neoptera can be identified reliably. Based on this interpretation, the ancestral condition of the insect wing base structure is discussed.     

POPULATIONS OF MONARCH BUTTERFLIES WITH DIFFERENT MIGRATORY BEHAVIORS SHOW DIVERGENCE IN WING MORPHOLOGY

The demands of long‐distance flight represent an important evolutionary force operating on the traits of migratory species. Monarchs are widespread butterflies known for their annual migrations in North America. We examined divergence in wing morphology among migratory monarchs from eastern and western N. America, and nonmigratory monarchs in S. Florida, Puerto Rico, Costa Rica, and Hawaii. For the three N. American populations, we also examined monarchs reared in four common environment experiments. We used image analysis to measure multiple traits including forewing area and aspect ratio; for laboratory‐reared monarchs we also quantified body area and wing loading. Results showed wild monarchs from all nonmigratory populations were smaller than those from migratory populations. Wild and captive‐reared eastern monarchs had the largest and most elongated forewings, whereas monarchs from Puerto Rico and Costa Rica had the smallest and roundest forewings. Eastern monarchs also had the largest bodies and high measures of wing loading, whereas western and S. Florida monarchs had less elongated forewings and smaller bodies. Among captive‐reared butterflies, family‐level effects provided evidence that genetic factors contributed to variation in wing traits. Collectively, these results support evolutionary responses to long‐distance flight in monarchs, with implications for the conservation of phenotypically distinct wild populations.     

Evolutionary relationships of wing venation and wing size and shape in Aphidiinae (Hymenoptera: Braconidae)

We explored evolutionary changes in wing venation and wing size and shape in Aphidiinae, one of the well-known groups of parasitic wasps from the family Braconidae. Forewings of 53 species from 12 genera were examined, for which a molecular phylogeny was constructed on the basis of the mitochondrial barcoding gene COI. By covering all types of wing venation within the subfamily Aphidiinae and by using landmark-based geometric morphometrics and phylogenetic comparative methods, we tested whether evolutionary changes in wing shape correlate to the changes in wing venation and if both changes relate to wing size. The relationship between wing morphology and host specificity has been also investigated. We found that six types of wing venation, with different degree of vein reduction, could be recognized. Wing venation type is largely genus specific, except in the case of maximal reduction of wing venation which could be found across examined Aphidiinae taxa. The reconstruction of evolutionary changes in wing venation indicates that evolutionary changes in wing shape are related to the changes in wing size, indicating that miniaturization play a role in evolution of wing morphology while host specialization does not affect the wing shape within the subfamily Aphidiinae.     

蝉次目昆虫“足-消化道-马氏管”的形态/功能分化及其在蝉次目昆虫系统演化中的意义

对蝉次目3个总科(蝉总科,沫蝉总科,角蝉总科)代表类群(12种成虫)的足、消化道和马氏管的形态结构及其分化进行了比较形态学研究,提出蝉次目昆虫消化道及马氏管整体结构可被划分为两种类型的观点(蝉总科和沫蝉总科消化道及马氏管整体结构为同一种类型,角蝉总科消化道及马氏管整体结构为另一种类型),并分别绘制了两种类型的模式结构图;基于成虫的马氏管比较形态学研究,提出蝉次目昆虫成虫马氏管可被划分为6部分的观点,并分别绘制了角蝉科、叶蝉科、蝉科和沫蝉科成虫的马氏管区域分化模式结构图。研究结果表明,蝉次目昆虫的足、消化道、马氏管的形态、功能分化与其生物学、行为生态学特性等密切相关,其形态学特征既为蝉次目各类群的单系性提供了重要支持证据,也为进一步从行为学、生态学、生物学等方面探讨蝉次目的系统演化历史提供了新的信息;研究结果支持蝉总科和沫蝉总科为姊妹群的观点,即蝉次目3个总科的系统关系为角蝉总科+(蝉总科+沫蝉总科)。     

Uracil‐DNA glycosylases—Structural and functional perspectives on an essential family of DNA repair enzymes

Uracil‐DNA glycosylases (UDGs) are evolutionarily conserved DNA repair enzymes that initiate the base excision repair pathway and remove uracil from DNA. The UDG superfamily is classified into six families based on their substrate specificity. This review focuses on the family I enzymes since these are the most extensively studied members of the superfamily. The structural basis for substrate specificity and base recognition as well as for DNA binding, nucleotide flipping and catalytic mechanism is discussed in detail. Other topics include the mechanism of lesion search and molecular mimicry through interaction with uracil‐DNA glycosylase inhibitors. The latest studies and findings detailing structure and function in the UDG superfamily are presented.     

Wing colors based on arrangement of the multilayer structure of wing scales in lycaenid butterflies (Insecta: Lepidoptera)

Male wing colors and wing scale morphology were examined for three species of lycaenid butterflies: Chrysozephyrus ataxus, Favonius cognatus and F. jezoensis. Measurement of spectral reflectance on the wing surface with a spectrophotometer revealed species‐specific reflection spectra, with one or two peaks in the ultraviolet and/or green ranges. Observations of wing scales using an optical microscope revealed that light was reflected from the inter‐ridge regions, where transmission electron microscopy revealed a multilayer structure. Based on the multilayer dimensions obtained, three models were devised and compared to explain the measured reflectance spectrum. The results showed that the best fit is a model in which thicknesses of thin films of the multilayer system are not constant and air spaces between cuticle layers are more or less packed with cuticle spacers. This suggests that the specific wing colors of the species examined are produced by the species‐specific arrangement of the multilayer structure of wing scales.