Phylogeny and the modalities of acoustic diversification in extant Eneopterinae (Insecta, Orthoptera, Grylloidea, Eneopteridae)

Calling with a tegminal stridulatory apparatus is widespread in crickets. However, the evolution of cricket stridulums has been poorly studied and then only on the basis of prephylogenetic models, which are unable to account for the huge diversity recently documented for acoustic features in crickets. The present paper focuses on the evolution of acoustic devices in the subfamily Eneopterinae. This is the first attempt to reconstruct the phylogeny of a large and diverse cricket clade in order to analyze the evolution of emitting structures using precise homology statements. In the first step, we reconstruct the phylogeny of this clade using a morphological data set of 193 characters and 45 taxa. The resultant phylogeny supports the monophyly of the subfamily and that of the 13 genera represented by at least two species in our taxonomic sample. Phylogenetic relationships within the subfamily also support the definition of five tribes: Eurepini, Eneopterini, Nisitrini, Xenogryllini and Lebinthini. In the second step, the evolution of acoustic devices is studied by optimization of venation characters defined on precise homology statements. As hypothesized by previous authors, losses of acoustic communication occur independently in the course of eneopterine evolution; however, they happen abruptly with no intermediate state. Our results also document for the first time the modalities of forewing evolution: the diversification of male forewing venation originates from two processes, a continuous and regular modification process, responsible for slight venation change; and an irregular, more intense punctuated process, allowing the emergence of different venations. This diversification process with sudden changes could be related to the occurrence of acoustic novelties in advertisement calls.     

High-frequency calling in Eneopterinae crickets (Orthoptera, Grylloidea, Eneopteridae): adaptive radiation revealed by phylogenetic analysis

The dominant frequency (Fd) of the cricket calling song commonly ranges from 2 to 8 kHz because of physical constraints due to small size and stridulum functioning. However some Eneopterinae crickets are known to call with Fds of 10–15 kHz, and one species ( Eneoptera guyanensis ) produces a modulated call with both a low and a high Fd. We studied Fd evolution with respect to phylogeny in the whole Eneopterinae subfamily to reconstruct its pattern of transformation. The phylogenetic pattern resulting from the analysis showed that Fd is relatively stable through the whole clade: the Fd ancestral state (3–7.9 kHz) has been modified only once, with the occurrence of a high Fd in the clade [ Cardiodactylus ( Lebinthus–Agnotecous )]: high Fd replaced low Fd, resulting in high-frequency calling songs. In E. guyanensis , the pattern of frequency change is different: a high Fd component has been added to the low ancestral Fd, resulting in frequency modulation. Investigation of cladogenesis rate indicated that the onset of high Fd in [ Cardiodactylus ( Lebinthus–Agnotecous )] was accompanied by a high cladogenesis rate, supporting a hypothesis of adaptive radiation for high-frequency calling (phylogeny criterion of adaptation). High frequencies are particularly problematic for long-range communication, especially for forest-living species, because of the increase of excess attenuation with frequency. The effectiveness of high-frequency calling is discussed in the clade [ Cardiodactylus ( Lebinthus–Agnotecous )] in relation to the behavioural ecology of the species.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 83 , 577–584.     

Phylogenetic systematics of Pseudolebinthus, a new genus of Eneopterinae crickets (Orthoptera, Grylloidea, Eneopteridae) from south-east Africa

Abstract.  Within a framework of historical analysis of Eneopterinae crickets, the genus Pseudolebinthus Robillard gen.n. and two new species P. africanus Robillard, sp.n. and P. whellani Robillard, sp.n. , endemic from south-east Africa, are described. A cladistic analysis using 198 morphological characters and 47 terminals assessed the phylogenetic position of the new taxa within the subfamily. The resultant topologies support the previously proposed phylogeny for the subfamily and contained tribes. The monophyly of Pseudolebinthus is supported strongly as well as its sister relationship with Xenogryllus within the tribe Xenogryllini. A key to Eneopterinae tribes, Xenogryllini genera and Pseudolebinthus species is given. Taxonomic, evolutionary and acoustic issues raised by the recognition of Pseudolebinthus are discussed.     

Bioacoustics of the Neotropical Eneopterinae (Orthoptera,Grylloidea, Gryllidae)

In members of the cricket subfamily Eneopterinae (Orthoptera, Grylloidea), songs with powerful high-frequency (HF) harmonics have evolved, which likely represents a distinctive acoustic adaptation. In this study, we analysed or reanalysed the songs of the three eneopterine genera present in the Neotropics to evaluate whether they also possess high-amplitude HF components. We present new data and combine several lines of evidence to interpret or reinterpret the calling signals of a representative species for each genus. We used new recordings in order to detect and analyse potential HF components of the songs. Stridulatory files were measured, and stridulation was studied using high-speed video recordings. The results suggest that all eneopterine genera from the Neotropics use HFs to communicate, based on the rich harmonic content of their songs. Strikingly, the Neotropical eneopterines possess high dominant frequencies, recalling the patterns observed in the tribe Lebinthini, the most speciose tribe of the subfamily distributed in the Western Pacific region and in Southeast Asia: Ligypterus and Ponca show dominant harmonic peaks, whereas Eneoptera possesses unique features. The three species under study, however, deal differently with HFs.     

The complex stridulatory behavior of the cricket Eneoptera guyanensis Chopard (Orthoptera: Grylloidea: Eneopterinae)

Crickets produce stridulated sounds by rubbing their forewings together. The calling song of the cricket species Eneoptera guyanensis Chopard, 1931 alternates two song sections, at low and high dominant frequencies, corresponding to two distinct sections of the stridulatory file. In the present study we address the complex acoustic behavior of E. guyanensis by integrating information on the peculiar morphology of the stridulatory file, the acoustic analysis of its calling song and the forewing movements during sound production. The results show that even if E. guyanensis matches the normal cricket functioning for syllable production, the stridulation involves two different closing movements, corresponding to two types of syllables, allowing the plectrum to hit alternately each differentiated section of the file. Transition syllables combine high and low frequencies and are emitted by a complete forewing closure over the whole file. The double-teeth section of the stridulatory file may be used as a multiplier for the song frequency because of the morphological multiplication due to the double teeth, but also because of an increase of wing velocity when this file section is used. According to available phylogenetic and acoustic data, this complex stridulation may have evolved in a two-step process.     

Phylogenetic systematics and evolution of Agnotecous in New Caledonia (Orthoptera: Grylloidea, Eneopteridae)

Abstract. Within a framework for historical analysis of Eneopterinae biogeography the New Caledonian endemic cricket genus Agnotecous Saussure, 1878 is revised: the eight already known species are diagnosed and six new species described, A. azurensis Desutter‐Grandcolas sp.n. , A. chopardi Desutter‐Grandcolas sp.n. , A. clarus Desutter‐Grandcolas sp.n. , A. doensis Desutter‐Grandcolas sp.n. , A. meridionalis Desutter‐Grandcolas sp.n. and A. occidentalis Desutter‐Grandcolas sp.n. Four species groups are characterized by male genitalic structures. Identification keys are provided for both males and females. A cladistic analysis was performed using fifty‐eight morphological characters. The two resultant topologies, which differ only in topology of three apical species, support the monophyly of Agnotecous and that of the four species groups. Preliminary hypotheses of Eneopterinae historical biogeography are derived from phylogenetic and distributional data.     

Evolution of the cercal sensory system in a tropical cricket clade (Orthoptera: Grylloidea: Eneopterinae): a phylogenetic approach

The diversity of sensory systems in animals has poorly been explored on a phylogenetic basis at the species level. We addressed this issue using cricket cerci, comprising abdominal appendages covered with touch‐ and air‐sensitive hairs. Scanning electron microscopy measurements and spatial analyses of hair positioning were used to quantify the structural diversity of cercal structures. Eighteen Eneopterinae and two Gryllidae (outgroups) were studied from a phylogenetic perspective. Cerci were revealed to be complex, diverse, and variable between cricket species. Based on maximum likelihood estimations, the ancestral Eneopterinae cercus had a small size, and its hair equipment allowed the use of both air and touch mechanoreception. The evolution of Eneopterinae cerci was mainly unconstrained by the phylogeny; it was rather a punctuated process, involving apical transformations, and was mostly unrelated to environmental patterns. All studied species have enhanced their overall perceptive capacities compared to the ancestor. Most have longer cerci with more and/or longer hairs. Sensory abilities have improved either in the direction of touch or air movement detection, or both, without discarding the potential for any sensory capacity that was already present ancestrally. This pattern is consistent with the hypothesis of an evolutionary trade‐off for sensory performances. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 614–631.     

中国长须蟋属Aphonoides 一新种(直翅目: 蟋蟀总科: 虫吉蟋科)

本文报道了采自中国福建省蟋蟀总科长须蟋属的1个新种武夷长须蟋Aphonoides wuyiensis Yin.同时列出中国长须蟋属已知种类的分种检索表.模式标本保存于中国科学院上海植物生理生态研究所昆虫标本馆.     

Functional forewing morphology and stridulation in crickets (Orthoptera, Grylloidea)

Forewing morphology and infrastructure are analysed in three cricket species ( Gryllus campestris, Oecanthus pellucens and Lerneca fuscipennis ) and checked in 20 other genera. A strong dorsoventral asymmetry is demonstrated for the first time. The upper side of the tegmina is covered with hexagonal, more or less high crests forming reliefs. On the lower side, annulate, flat and thick veins exist. The distribution of the hexagons and that of the different vein types is uneven on the forewing surfaces. Their significance in forewing functional morphology is discussed in relation to stridulation and to current knowledge on cricket sound production mechanisms. Their extent and distribution, together with the number and strength of the veins and the surface of wing cells, could account for the vibrational characteristics of the cricket forewing and explain the diverse results obtained by several authors on Gryllus and Oecanthus .     

Phylogeny of the grasshopper family Pyrgomorphidae (Caelifera,Orthoptera) based on morphology

The family P yrgomorphidae (O rthoptera: C aelifera) is considered one of the most colourful grasshopper families, which contains about 500 species distributed worldwide. Commonly referred to as gaudy or bush grasshoppers, many pyrgomorphs are known to be aposematic and capable of sequestering plant secondary compounds. Several species are considered important agricultural pests, while some species are culturally important. Nevertheless, the phylogeny of this family has never been proposed using modern cladistic methods. In this study, we present a phylogenetic analysis of P yrgomorphidae, based on 119 morphological characters with 269 character states, covering 28 out of 31 current recognized tribes. We recovered the monophyly of the family and one of the two currently recognized subfamilies, O rthacridinae. P yrgomorphinae was recovered as paraphyletic. Based on the most parsimonious tree, we propose four main clades and discuss the biology and biogeography of members of these clades. This is the first step towards building a natural classification for P yrgomorphidae, which is an excellent model system for studying the evolution of interesting traits such as wing development, warning coloration and chemical defence.     

Phylogeny of xanthopygine rove beetles (Coleoptera) based on six molecular loci

The rove beetle subtribe Xanthopygina (Coleoptera: Staphylinidae: Staphylininae: Staphylinini) is a species‐rich group of 27 neotropical genera that contains some of the largest and most brightly coloured of all staphylinid beetles. The monophyly of the subtribe has never been tested before, using a large dataset of taxa and genes. Bayesian and maximum likelihood analyses are used on individual genes (COI, 28S rDNA, wingless, arginine kinase, CAD and topoisomerase I) and the partitioned concatenated dataset to test for monophyly and examine the relationships among Xanthopygina genera. Xanthopygina (excluding Philothalpus) are shown to be a monophyletic group with strong support values. The genus Philothalpus is removed from Xanthopygina and placed in the tribe Staphylinini as incertae sedis. Four distinct clades of Xanthopygina genera are recognized. The origin of Xanthopygina is hypothesized to be in the Late Cretaceous or later and the origin of myrmecophilous adaptations is discussed.     

Phylogeny of thrips (Insecta: Thysanoptera) based on five molecular loci

The order Thysanoptera (Paraneoptera), commonly known as thrips, displays a wide range of behaviours, and includes several pest species. The classification and suggested relationships among these insects remain morphologically based, and have never been evaluated formally with a comprehensive molecular phylogenetic analysis. We tested the monophyly of the suborders, included families and the recognized subfamilies, and investigated their relationships. Phylogenies were reconstructed based upon 5299 bp from five genetic loci: 18S ribosomal DNA, 28S ribosomal DNA, Histone 3, Tubulin‐alpha I and cytochrome oxidase c subunit I. Ninety‐nine thrips species from seven of the nine families, all six subfamilies and 70 genera were sequenced. Maximum parsimony, maximum likelihood and Bayesian analyses all strongly support a monophyletic Tubulifera and Terebrantia. The families Phlaeothripidae, Aeolothripidae, Melanthripidae and Thripidae are recovered as monophyletic. The relationship of Aeolothripidae and Merothripidae to the rest of Terebrantia is equivocal. Molecular data support previous suggestions that Aeolothripidae or Merothripidae could be a sister to the rest of Terebrantia. Four of the six subfamilies are recovered as monophyletic. The two largest subfamilies, Phlaeothripinae and Thripinae, are paraphyletic and require further study to understand their internal relationships.     

Testing concordance in species boundaries using acoustic,morphological, and molecular data in the field cricket genus Itaropsis (Orthoptera: Grylloidea,Gryllidae: Gryllinae)

In most taxa, species boundaries are inferred based on differences in morphology or DNA sequences revealed by taxonomic or phylogenetic analyses. In crickets, acoustic mating signals or calling songs have species‐specific structures and provide a third data set to infer species boundaries. We examined the concordance in species boundaries obtained using acoustic, morphological, and molecular data sets in the field cricket genus Itaropsis. This genus is currently described by only one valid species, Itaropsis tenella, with a broad distribution in western peninsular India and Sri Lanka. Calling songs of males sampled from four sites in peninsular India exhibited significant differences in a number of call features, suggesting the existence of multiple species. Cluster analysis of the acoustic data, molecular phylogenetic analyses, and phylogenetic analyses combining all data sets suggested the existence of three clades. Whatever the differences in calling signals, no full congruence was obtained between all the data sets, even though the resultant lineages were largely concordant with the acoustic clusters. The genus Itaropsis could thus be represented by three morphologically cryptic incipient species in peninsular India; their distributions are congruent with usual patterns of endemism in the Western Ghats, India. Song evolution is analysed through the divergence in syllable period, syllable and call duration, and dominant frequency. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 164 , 285–303.     

Phylogenetic relationships in the cricket tribe Xenogryllini (Orthoptera,Gryllidae, Eneopterinae) and description of the Indian genus Indigryllus gen. nov.

The subfamily Eneopterinae is known greatly for its diversified acoustic modalities and disjunct distribution. Within Eneopterinae, tribe Lebinthini is the most studied group, due to its highest species diversity (ca. 150 species in 12 genera), endemic distribution on the islands of Southeast Asia and of the South West Pacific, males’ ability to produce high‐frequency calling songs, and evolution of females’ vibrational response. To investigate the distribution pattern and diversification of acoustic and behavioral attributes in a larger frame, clear understanding of phylogenetic relationships within other tribes of Eneopterinae is vital. In this study, we focus on the tribe Xenogryllini, sister group of Lebinthini. Xenogryllini, as opposed to Lebinthini, is known by fewer species (11 species in two genera), distributed widely in continental Asia and Africa, and for producing low‐frequency calling songs. We describe a new genus Indigryllus with a new species of the tribe Xenogryllini, discovered from the southwest of India. We used eight molecular genetic markers to reconstruct the phylogenetic relationships. The resultant phylogenetic tree is used to compare and discuss distribution patterns and acoustic modalities between Lebinthini and Xenogryllini.     

Phylogeny of the sea spiders (Arthropoda, Pycnogonida) based on direct optimization of six loci and morphology

Higher‐level phylogenetics of Pycnogonida has been discussed for many decades but scarcely studied from a cladistic perspective. Traditional taxonomic classifications are yet to be tested and affinities among families and genera are not well understood. Pycnogonida includes more than 1300 species described, but no systematic revisions at any level are available. Previous attempts to propose a phylogeny of the sea spiders were limited in characters and taxon sampling, therefore not allowing a robust test of relationships among lineages. Herein, we present the first comprehensive phylogenetic analysis of the Pycnogonida based on a total evidence approach and Direct Optimization. Sixty‐three pycnogonid species representing all families including fossil taxa were included. For most of the extant taxa more than 6 kb of nuclear and mitochondrial DNA and 78 morphological characters were scored. The most parsimonious hypotheses obtained in equally weighted total evidence analyses show the two most diverse families Ammotheidae and Callipallenidae to be non‐monophyletic. Austrodecidae + Colossendeidae + Pycnogonidae are in the basal most clade, these are morphologically diverse groups of species mostly found in cold waters. The raising of the family Pallenopsidae is supported, while Eurycyde and Ascorhynchus are definitely separated from Ammotheidae. The four fossil taxa are grouped within living Pycnogonida, instead of being an early derived clade. This phylogeny represents a solid framework to work towards the understanding of pycnogonid systematics, providing a data set and a testable hypothesis that indicate those clades that need severe testing, especially some of the deep nodes of the pycnogonid tree and the relationships of ammotheid and callipallenid forms. The inclusion of more rare taxa and additional sources of evidence are necessary for a phylogenetic classification of the Pycnogonida. © The Willi Hennig Society 2006.     

Phylogeny of bird-grasshopper subfamily Cyrtacanthacridinae (Orthoptera: Acrididae) and the evolution of locust phase polyphenism

Locust phase polyphenism is an extreme form of density-dependent phenotypic plasticity in which solitary and cryptic grasshoppers can transform into gregarious and conspicuous locusts in response to an increase in local population density. We investigated the evolution of this complex phenotypic plasticity in a phylogenetic framework using a morphological phylogeny of Cyrtacanthacridinae, which contains some of the most important locust species, and a comprehensive literature review on the biology and ecology of all known members of the subfamily. A phylogenetic analysis based on 71 morphological characters yielded a well-resolved tree and found that locust phase polyphenism evolved multiple times within the subfamily. The literature review demonstrated that many cyrtacanthacridine species, both locust and sedentary, are capable of expressing density-dependent color plasticity. When this color plasticity was divided into two smaller components, background coloration and development of black pigmentation, and when these plastic traits were optimized on to the phylogeny, we found that the physiological mechanisms underlying this plasticity were plesiomorphic for the subfamily. We also found that different locust species in Cyrtacanthacridinae express both similarities and differences in their locust phase polyphenism. Because locust phase polyphenism is a complex syndrome consisting of numerous plastic traits, we treat it as a composite character and dissected it into smaller components. The similarities among locust species could be attributed to shared ancestry and the differences could be attributed to the certain components of locust phase polyphenism evolving at different rates.
© The Willi Hennig Society 2007.     

Inferring species boundaries using acoustic and morphological data in the ground cricket genus Gymnogryllus (Orthoptera: Grylloidea: Gryllinae)

An important function of song production by male crickets is to attract conspecific females. These sound signals can be used to infer species boundaries as they can provide indirect evidence for reproductive isolation. However, many studies of orthopteran diversity in South-east Asia are based mainly on morphology and only occasionally acoustics. As such, there is a lack of information on how acoustic data can be congruent with morphological data when used to delineate species. Crickets of the genus Gymnogryllus (Grylloidea, Gryllidae), are such an example. Gymnogryllus are relatively speciose, but their calling songs have not been studied. We collected specimens and calling songs of five Gymnogryllus species from South-east Asia. The acoustic parameters of the calls, along with male tegminal venation and morphology genitalia, were compared. All data types showed congruency in distinguishing G. sylvestris and G. leucostictus from each other and from the other species. Inferring species boundaries for G. angustus, G. malayanus, and G. unexpectus using acoustics and tegminal morphometry proves to be more challenging. While acoustics, tegminal morphometry, and genital morphology are likely to be useful for inferring species of Gymnogryllus from different species groups, greater coverage of taxa is needed to resolve taxonomy of closely related Gymnogryllus.     

Chromosomal polymorphism and speciation in the genusEunemobius (Orthoptera: Grylloidea)

Karyotypes are described for the three species of ground crickets belonging to the North American genusEunemobius. All species possess three pairs of metacentric autosomes and a submetacentric X-chromosome. The sex-determination mechanism is XX-XO with 2n=7 in males and 2n=8 in females. There is no evidence that chromosomal rearrangements have been involved in speciation in the group.     

Phylogeny and systematics of the subfamily Bryocorinae based on morphology with emphasis on the tribe Dicyphini sensu Schuh,

The classification of the hyperdiverse true bug family Miridae is far from settled, and is particularly contentious for the cosmopolitan subfamily Bryocorinae. The morphological diversity within the subfamily is pronounced, and a lack of explicit character formulation hampers stability in the classification. Molecular partitions are few and only a handful of taxa have been sequenced. In this study the phylogeny of the subfamily Bryocorinae has been analysed based on morphological data alone, with an emphasis on evaluating the tribe Dicyphina sensu Schuh, 1976, within which distinct groups of taxa exist. A broad sample of taxa was examined from each of the bryocorine tribes. A broad range of outgroup taxa from most of the other mirid subfamilies was also examined to test for bryocorine monophyly, ingroup relationships and to determine character polarity. In total a matrix comprising 44 ingroup, 15 outgroup taxa and 111 morphological characters was constructed. The phylogenetic analysis resulted in a monophyletic subfamily Bryocorinae sensu Schuh (1976, 1995), except for the genus Palaucoris, which is nested within Cylapinae. The tribe Dicyphini sensu Schuh (1976, 1995) has been rejected. The subtribe Odoniellina is synonymized with the subtribe Monaloniina and the subtribes Dicyphina, Monaloniina and Eccritotarsina are now elevated to tribal level, with the Dicyphini now restricted in composition and definition. The genus Felisacus is highly autapomorphic and a new tribe – the Felisacini – is erected for the included taxa. This phylogeny of the tribes of the Bryocorinae comprises the following sister‐group relationships: Dicyphini ((Bryocorini + Eccritotarsini)(Felisicini + Monaloniini)).     

Phylogeny of Henicopidae (Chilopoda: Lithobiomorpha): a combined analysis of morphology and five molecular loci

Abstract. Relationships in Henicopidae, the dominant southern temperate clade of Lithobiomorpha, are appraised based on parsimony analysis of forty-nine morphological characters and sequence data from five loci (nuclear ribosomal RNAs 18S and 28S, mitochondrial ribosomal RNAs 12S and 16S, protein-coding mitochondrial cytochrome c oxidase I). A combined analysis of these data used direct character optimization, and tested stability of hypotheses through parameter-sensitivity analysis. The morphology dataset highlighted the mandibles as a source of new characters. Morphology, as well as the most congruent parameters for the sequence data and combined analysis, resolved Zygethobiini within Henicopini. Groups retrieved by combined analysis of the sequences and combination with morphology for all parameters include Anopsobiinae/Henicopinae, Lamyctes + Lamyctinus + Henicops , Paralamyctes ( Paralamyctes ), and a clade that groups the southeastern Australian/New Zealand Paralamyctes ( Haasiella ) and P . ( Thingathinga ). Paralamyctes (including Haasiella ) is a Gondwanan clade in the most congruent cladograms based on all molecular data and combination with morphological data. Biogeographic analysis of subtrees for Paralamyctes resolved the interrelationships of Gondwana as (Patagonia ((New South Wales + southeastern Queensland) ((Tasmania) (southern Africa + India) (New Zealand + north Queensland)))).