Phylogeny of the genus Aleochara inferred from mitochondrial cytochrome oxidase sequences (Coleoptera: Staphylinidae)

Wow assingi gen. and spec. n., with description of a new tribe of Aleocharinae (Coleoptera, Staphylinidae)

A new tribe, Wowini Jaoszyski, Maruyama & Klimaszewski, trib. n., based on a new genus, Wow Jaoszyski, Maruyama & Klimaszewski, gen. n., is established to accommodate an extraordinary new species of aleocharine rove beetles, Wow assingi Jaoszyski, Maruyama & Klimaszewski, spec. n. The species was recently discovered in Yunnan, China. It shows a set of characters unknown in this combination in any other nominal taxon of Aleocharinae. The external morphology and genital male structures are illustrated and discussed. A possible close relationship of the new tribe with Oxypodinini Fenyes is proposed as a working hypothesis, and a parallel evolution of unusual cephalic transformations between Wowini and Keratodegnathus Pace (Lomechusini) is discussed.

Revision of Brazilian species of Aleochara Gravenhorst of the subgenus Xenochara Mulsant & Rey (Coleoptera: Staphylinidae: Aleocharinae)

Aleochara species occur in fly-infested habitats. The larvae feed on the pupae of cyclorraphous Diptera. In Brazil, four subgenera and approximately 30 species have been found. This study provides a taxonomic revision of the Brazilian species of the subgenus Xenochara. Eight species are recognized: A. (X.) puberula Klug, 1833, A. (X.) verberans Erichson, 1839, A. (X.) simulatrix Sharp, 1883, A. (X.) taeniata Erichson, 1839, A. (X.) capitinigra sp. nov., A. (X.) repetita Sharp, 1887, A. (X.) lapidicola (Sahlberg, 1844) and A. (X.) leivasorum sp. nov. One species is revalidated: A. (X.) lapicola, a former junior synonym of A. (X.) taeniata. Two synonyms are proposed: A. opacula Bernhauer, 1901 as a junior synonym of A. (X.) repetita, and A. festiva Pace, 1990 as a junior synonym of A. (X.) lapidicola. Finally, a species key and a checklist with all synonyms are provided for the Brazilian species of Aleochara (Xenochara).

Development of markers using microsatellite loci of two rove beetle species, Paederus fuscipes Curtis and Aleochara (Aleochara) curtula Goeze (Coleoptera: Staphylinidae), followed by analyses of genetic diversity and population structure

BACKGROUND

The family Staphylinidae is the most speciose beetle group in the world. The outbreaks of two staphylinid species, Paederus fuscipes and Aleochara (Aleochara) curtula, were recently reported in South Korea. None of research about molecular markers and genetic diversity have been conducted in these two species.

OBJECTIVE

To develop microsatellite markers and analyze the genetic diversity and population structures of two rove beetle species.

METHODS

NGS was used to sequence whole genomes of two species, Paederus fuscipes and Aleochara (Aleochara) curtula. Microsatellite loci were selected with flanking primer sequences. Specimens of P. fuscipes and A. curtula were collected from three localities, respectively. Genetic diversity and population structure were analyzed using the newly developed microsatellite markers.

RESULTS

The number of alleles ranged 5.727-6.636 (average 6.242) and 2.182-5.364 (average 4.091), expected heterozygosity ranged 0.560-0.582 (average 0.570) and 0.368-0.564 (average 0.498), observed heterozygosity ranged 0.458-0.497 (average 0.472) and 0.418-0.644 (average 0.537) in P. fuscipes and A. curtula, respectively. Population structure indicates that individuals of A. curtula are clustered to groups where they were collected, but those of P. fuscipes are not.

CONCLUSION

Population structures of P. fuscipes were shallow. In A. curtula, however, it was apparent that the genetic compositions of the populations are different significantly depending on collection localities.

Total-evidence backbone phylogeny of Aleocharinae (Coleoptera: Staphylinidae)

Phylogenetic studies of Aleocharinae rove beetles, arguably one of the least known and the largest insect lineages, are compromised by its enormous taxonomic diversity. DNA, a powerful resource for phylogenetics, is not available for numerous extant aleocharine species. We provide a broad comparative morphological study of Aleocharinae to frame molecular datasets for total-evidence analyses. Using full-body dissections and slide-mounting techniques for light microscopy supplemented by scanning electron microscopy, we constructed a morphological matrix across all major taxa focused on non-inquiline tribes of Aleocharinae and outgroups. Phylogenetic analyses of this matrix concatenated with earlier published DNA loci and including exemplar taxa lacking molecular data, resolved outstanding controversies and, among other novelties, showed that: the Habrocerinae + Trichophyinae clade is sister group to Aleocharinae; Hypocyphtini are sister to the rest of the "higher Aleocharinae"; Taxicerini are sister to Aleocharini; Hoplandriini and Placusini are nested within a polyphyletic Oxypodini; Hoplandriini are sister to Meoticina; and Actocharini are nested within Liparocephalini. For the first time, morphological synapomorphies are identified for some large clades of Aleocharinae. In addition, 1252 high-resolution microphotographs of aleocharine structures are made available online with the entire matrix for future research.

Bacterial Community Diversity Harboured by Interacting Species

All animals are infected by microbial partners that can be passengers or residents and influence many biological traits of their hosts. Even if important factors that structure the composition and abundance of microbial communities within and among host individuals have been recently described, such as diet, developmental stage or phylogeny, few studies have conducted cross-taxonomic comparisons, especially on host species related by trophic relationships. Here, we describe and compare the microbial communities associated with the cabbage root fly Delia radicum and its three major parasitoids: the two staphylinid beetles Aleochara bilineata and A. bipustulata and the hymenopteran parasitoid Trybliographa rapae. For each species, two populations from Western France were sampled and microbial communities were described through culture independent methods (454 pyrosequencing). Each sample harbored at least 59 to 261 different bacterial phylotypes but was strongly dominated by one or two. Microbial communities differed markedly in terms of composition and abundance, being mainly influenced by phylogenetic proximity but also geography to a minor extent. Surprisingly, despite their strong trophic interaction, parasitoids shared a very low proportion of microbial partners with their insect host. Three vertically transmitted symbionts from the genus Wolbachia, Rickettsia, and Spiroplasma were found in this study. Among them, Wolbachia and Spiroplasma were found in both the cabbage fly and at least one of its parasitoids, which could result from horizontal transfers through trophic interactions. Phylogenetic analysis showed that this hypothesis may explain some but not all cases. More work is needed to understand the dynamics of symbiotic associations within trophic network and the effect of these bacterial communities on the fitness of their hosts.

Revision of the subgenus Tinotus Sharp, stat. n., of the parasitoid rove-beetle genus Aleochara Gravenhorst (Coleoptera, Staphylinidae, Aleocharinae) from Japan, Taiwan, and the Russian Far East

The subgenus Tinotus Sharp, 1833, stat. n., of the genus Aleochara Gravenhorst, 1802 (Aleocharini: Aleocharina) from Japan, Taiwan, and the Russian Far East is revised. Tinotus is a new record from the latter two regions. Three species are recognized: Aleochara (Tinotus) morion Gravenhorst, 1802, comb. n. [Japan (new record), the Russian Far East (new record)], Aleochara (Tinotus) eoanom. n. [replacement name for Tinotusjaponicus Cameron, 1933; Japan, Taiwan (new record)], and Aleochara (Tinotus) takashiisp. n. (central Honshû, Japan). The systematic position of Tinotus is discussed. All species are (re-)described, keyed, and figured. A world checklist of Tinotus species, comprising 40 valid species, is provided in an appendix. Additional taxonomic changes are proposed, including a new synonymy, a revalidation, 13 new replacement names, and 27 new combinations.

Na+/K+-ATPase resistance and cardenolide sequestration: basal adaptations to host plant toxins in the milkweed bugs (Hemiptera: Lygaeidae: Lygaeinae)

Despite sequestration of toxins being a common coevolutionary response to plant defence in phytophagous insects, the macroevolution of the traits involved is largely unaddressed. Using a phylogenetic approach comprising species from four continents, we analysed the ability to sequester toxic cardenolides in the hemipteran subfamily Lygaeinae, which is widely associated with cardenolide-producing Apocynaceae. In addition, we analysed cardenolide resistance of their Na(+)/K(+)-ATPases, the molecular target of cardenolides. Our data indicate that cardenolide sequestration and cardenolide-resistant Na(+)/K(+)-ATPase are basal adaptations in the Lygaeinae. In two species that shifted to non-apocynaceous hosts, the ability to sequester was secondarily reduced, yet Na(+)/K(+)-ATPase resistance was maintained. We suggest that both traits evolved together and represent major coevolutionary adaptations responsible for the evolutionary success of lygaeine bugs. Moreover, specialization on cardenolides was not an evolutionary dead end, but enabled this insect lineage to host shift to cardenolide-producing plants from distantly related families.

How old are the rove beetles (Insecta: Coleoptera: Staphylinidae) and their lineages? Seeking an answer with DNA

The phylogeny and related evolutionary history of rove beetles (Coleoptera, Staphylinidae) remain unclear. This study provides phylogenetic analyses for the family based on three genes (mitochondrial COI, nuclear protein-coding wingless and a portion of the ribosomal 28S rDNA) including 2413 bp for 104 taxa representing most major staphylinid lineages. The subfamilies Oxyporinae, Paederinae, Steninae, and Proteininae are all well-supported clades, as evidenced by all three inference methods, namely maximum parsimony, Bayesian inference, and maximum likelihood. From fossils available for calibration, the divergence time of the main lineages in the family is estimated based on an uncorrelated lognormal relaxed molecular clock analysis method. The molecular clock analysis suggests that the family Staphylinidae dates from approximately the Early Triassic epoch and the most lineages of the family started to radiate from the Late Jurassic to the Early Paleogene.

Molecular phylogeny reveals multiple origins of seashore colonisation in the genus Aleochara Gravenhorst (Coleoptera : Staphylinidae : Aleocharinae)

A revised molecular phylogeny of the genus Aleochara Gravenhorst is presented. The dataset comprised partial mitochondrial cytochrome c oxidase I (COI) (1373 bp), COII (577 bp), and the complete sequences of tRNA leucine (71 bp) between them, for 56 Aleochara species and 8 outgroups. We added 15 populations of 8 coastal species: A. fucicola Sharp, A. littoralis (Mäklin), A. nubis (Assing), A. puetzi (Assing), A. squalithorax Sharp, A. sulcicollis Mannerheim, A. trisulcata Weise and A. zerchei (Assing). All phylogenetic analyses strongly supported the monophyly of the genus Aleochara, a curtula clade, a bilineata clade, and four other clades (A–D, described later) containing the coastal species. Based on the phylogenies, we hypothesise that there are four independent origins of specialisation to a coastal habitat in the genus Aleochara (clades A–D). Clade A (Emplenota and Triochara), with nine species, is the most successful lineage in terms of species number and broad distribution range.

Molecular phylogeny of the Athetini-Lomechusini-Ecitocharini clade of aleocharine rove beetles (Insecta)

Elven, E., Bachmann, L. & Gusarov V. I. (2012) Molecular phylogeny of the Athetini-Lomechusini-Ecitocharini clade of aleocharine rove beetles (Insecta). -Zoologica Scripta, 41, 617-636.It has previously been shown that the Aleocharinae tribes Athetini and Lomechusini form a well-supported clade, which also includes the small Neotropical tribe Ecitocharini. However, neither Athetini nor Lomechusini were recovered as monophyletic. In this study, we addressed the basal phylogenetic relationships among the three tribes using sequence data from (i) a mitochondrial fragment covering the COI, Leu2 and COII genes; (ii) a mitochondrial fragment covering part of the 16S gene, the Leu1 gene and part of the NADH 1 gene; and (iii) a part of the nuclear 18S gene, for 68 Athetini, 33 Lomechusini and 2 Ecitocharini species, plus representatives from 10 other tribes. The athetine subtribe Geostibina was recovered as sister group to the 'true Lomechusini', which included the type genus Lomechusa. The two clades formed a sister group to the main Athetini clade, which also included Ecitocharini and the 'false Lomechusini', a group of New World genera normally placed in Lomechusini. The following changes in classification are proposed: (i) Geostibina Seevers, 1978 is raised to tribal rank, and 13 Athetini genera are placed in Geostibini; (ii) Ecitodonia Seevers, 1965; Ecitopora Wasmann, 1887, and Tetradonia Wasmann, 1894 are moved from Lomechusini to Athetini; (iii) Ecitocharini Seevers, 1965 is placed in synonymy with Athetini; (iv) Discerota Mulsant & Rey, 1874 is tentatively included in Oxypodini; (v) Actocharina Bernhauer, 1907 is placed in synonymy with Hydrosmecta Thomson, 1858.

Phylogeny, biogeography and the stepwise evolutionary colonization of intertidal habitat in the Liparocephalini based on morphological and molecular characters (Coleoptera: Staphylinidae: Aleocharinae)

A phylogenetic analysis of the tribe Liparocephalini Fenyes is presented based on morphological and molecular characters. The data set comprised 50 adult morphological characters, partial COI (907 bp), COII (366 bp) and 12S rDNA (325-355 bp), and nearly complete sequences of 18S rDNA (1768-1902 bp) for 21 species. Eighteen species of liparocephaline beetles from all eight genera and three outgroups, are included. The sequences were analysed separately and simultaneously with morphological characters by direct optimization in the program POY4 and by partitioned Bayesian analysis for the combined data. The direct optimization (DO) tree for the combined data under equal weighting, which also shows a minimum incongruence length difference value, resulted in a monophyletic Liparocephalini with the following patterns of phylogenetic relationships (outgroup ((Baeostethus, Ianmoorea) (Paramblopusa ((Amblopusa, Halorhadinus) (Liparocephalus, Diaulota))))). A sensitivity analysis using 16 different parameter sets for the combined data shows the monophyly of the liparocephalines and all its genera under all parameter sets. Bayesian analysis resulted in topological differences in comparison with the DO tree under equal weighting only in the position of the genus Paramblopusa and clade (Amblopusa + Halorhadinus), which were reversed. Historical biogeography and the stepwise evolutionary colonization of intertidal habitat in the Liparocephalini are discussed. Based on the biogeographical analyses, we hypothesize that the ancestor of the Liparocephalini occurred along the Panthallassan Ocean, the direct antecedent of the Pacific Ocean, followed by repeated dispersals to the Nearctic from the Palearctic. We also hypothesize that ancestors of the Liparocephalini appear to have arisen in the littoral zone of beaches and then colonized rocky reef areas in the low tidal zone later through high- to mid-tide zones.  © The Willi Hennig Society 2009.

Queue up, please! Spermathecal filling in the rove beetle Drusilla canaliculata (Coleoptera, Staphylinidae)

Most studies on insect sperm motility have been conducted in vitro using artificial environments outside the animal's body. Only little is known about the function of motile insect sperm at different sites within the male or female genital tracts. We dissected genital tracts of female rove beetles (Drusilla canaliculata) to show that spermatozoa use their own motility to migrate from the spermatophore into the spermatheca. Our dissection method allowed direct observation and filming of the spermathecal filling process inside the female's genital tract. Spermatozoa were found to enter the spermatheca individually, sometimes in groups of two or three. Although exhibiting only weak motility and no progressive motion in buffer solution, the spermatozoa inside the female show vigorous lashing and reach an average velocity of 47.5 microm s(-1). To gain mobility and speed, the spermatozoa likely utilize the relatively small diameter of the spermathecal duct to push themselves off the duct walls, rather than swimming freely in seminal fluid. The spermatozoa (approximately 1,250 microm) are considerably longer than the distance they have to travel along the spermathecal duct (approximately 800 microm). Our study provides the first direct observation of active sperm migration within the female of an insect stressing the importance of the genital tract as a prerequisite for functional sperm motility.

The phylogeny of acorn weevils (genus Curculio) from mitochondrial and nuclear DNA sequences: the problem of incomplete data

We considered the contribution of two mitochondrial and two nuclear data sets for the phylogenetic reconstruction of 22 species of seed beetles in the genus Curculio (Coleoptera: Cuculionidae). A phylogenetic tree from representatives found on various hosts was inferred from a combined data set of mitochondrial DNA cytochrome oxidase subunit I, mitochondrial cytochrome b, nuclear elongation factor 1alpha, and nuclear phosphoglycerate mutase, used for the first time as a molecular marker. Separate parsimony analyses of each data set showed that individual gene trees were mainly congruent and often complementary in the support of clades but the analysis was complicated by failure of PCR amplification of nuclear genes for many taxa and hence missing data entries. When the four gene partitions were combined in a simultaneous analysis despite the missing data, this increased the resolution and taxonomic coverage compared to the individual source trees. Alternative approaches of combining the information via supertree methodology produced a comparatively less resolved tree, and hence seem inferior to combining data matrices even in cases where numerous taxa are missing. The molecular data suggest a classification of the European species into two species groups that are in accordance with morphological characteristics but the data do no support any of the previously recognised American species groups.