A new genus Anamalysia van Achterberg (Hymenoptera, Braconidae, Alysiinae), six new species, and two new combinations from India, Indonesia, Malaysia, Singapore, Thailand, and Vietnam

A new genus of the tribe Alysiini (Hymenoptera, Braconidae, Alysiinae) is described with specimens from India, Indonesia, Malaysia, Singapore, Thailand, and Vietnam, and six new species are described: Anamalysiaidiastimorpha sp. nov. (type species), A.knekosoma sp. nov., A.mellipes sp. nov., A.transversator sp. nov., A.vandervechti sp. nov., and A.vanhengstumi sp. nov.. We transfer one species from Coelalysia to Anamalysia: A.urbana (Papp, 1967) comb. nov. from Singapore and one species from Alysiasta to Anamalysia: A.triangulum (Fischer, 2006) comb. nov. from Malaysia, Laos, Indonesia and Vietnam. A key to the genus of Anamalysia is included.

Alternative prey mediate intraguild predation in the open field

BACKGROUND

Generalist predators that kill and eat other natural enemies can weaken biological control. However, pest suppression can be disrupted even if actual intraguild predation is infrequent, if predators reduce their foraging to lower their risk of being killed. In turn, predator-predator interference might be frequent when few other prey are available, but less common when herbivorous and detritus-feeding prey are plentiful. We used molecular gut-content analysis to track consumption of the predatory bug Geocoris sp. by the larger intraguild predator Nabis sp., in organic and conventional potato (Solanum tuberosum) fields.

RESULTS

We found that higher densities of both aphids and thrips, two common herbivores, correlated with higher probability of detecting intraguild predation. Perhaps, Nabis foraging for these herbivores also encountered and ate more Geocoris. Surprisingly, likelihood of intraguild predation was not strongly linked to densities of either Nabis or Geocoris, or farming system, suggesting a greater importance for prey than predator community structure. Intriguingly, we found evidence that Geocoris fed more often on the detritus-feeding fly Scaptomyza pallida with increasing predator evenness. This would be consistent with Geocoris shifting to greater foraging on the ground, where S. pallida would be relatively abundant, in the face of greater risk of intraguild predation.

CONCLUSION

Overall, our findings suggest that while herbivorous prey may heighten intraguild predation of Geocoris in the foliage, detritivores might support a shift to safer foraging on the ground. This provides further evidence that prey abundance and diversity can act to either heighten or relax predator-predator interference, depending on prey species identity and predator behavior. © 2022 Society of Chemical Industry.

Alternative prey and farming system mediate predation of Colorado potato beetles by generalists

BACKGROUND

Biological control by generalist predators can be mediated by the abundance and biodiversity of alternative prey. When alternative prey draw predator attacks away from the control target, they can weaken pest suppression. In other cases, a diverse prey base can promote predator abundance and biodiversity, reduce predator-predator interference, and benefit biocontrol. Here, we used molecular gut-content analysis to assess how community composition altered predation of Colorado potato beetle (Leptinotarsa decemlineata (Say)) by Nabis sp. and Geocoris sp. Predators were collected from organic or conventional potato (Solanum tuberosum L.) fields, encouraging differences in arthropod community composition.

RESULTS

In organic fields, Nabis predation of potato beetles decreased with increasing arthropod richness and predator abundance. This is consistent with Nabis predators switching to other prey species when available and with growing predator-predator interference. In conventional fields these patterns were reversed, however, with potato beetle predation by Nabis increasing with greater arthropod richness and predator abundance. For Geocoris, Colorado potato beetle predation was more frequent in organic than in conventional fields. However, Geocoris predation of beetles was less frequent in fields with higher abundance of the detritus-feeding fly Scaptomyza pallida Zetterstedt, or of all arthropods, consistent with predators choosing other prey when available.

CONCLUSION

Alternative prey generally dampened predation of potato beetles, suggesting these pests were less-preferred prey. Nabis and Geocoris differed in which alternative prey were most disruptive to feeding on potato beetles, and in the effects of farm management on predation, consistent with the two predator species occupying complementary feeding niches. © 2021 Society of Chemical Industry.

Alternative Prey and Predator Interference Mediate Thrips Consumption by Generalists

Generalist predators’ complex feeding relationships make it difficult to predict their contribution to pest suppression. Alternative prey can either distract predators from attacking pests, weakening biocontrol, or provide food that support larger predator communities to enhance it. Similarly, predator species might both feed upon and complement one another by occupying different niches. Here, we use molecular gut-content analysis to examine predation of western flower thrips (Frankliniella occidentalis) by two generalist predatory bugs, Geocoris sp. and Nabis sp. We collected predators from conventional and organic potato fields that differed in arthropod abundance and composition, so that we could draw correlations between abundance and biodiversity of predators and prey, and thrips predation. We found that alternative prey influenced the probability of detecting Geocoris predation of thrips through a complex interaction. In conventionally-managed potato fields, thrips DNA was more likely to be detected in Geocoris as total abundance of all arthropods in the community increased. But the opposite pattern was found in organic fields, where the probability of detecting thrips predation by Geocoris decreased with increasing total arthropod abundance. Perhaps, increasing abundance (from a relatively low baseline) of alternative prey triggered greater foraging activity in conventional fields, but drew attacks away from thrips in organic fields where prey were consistently relatively bountiful. The probability of detecting Geocoris predation of thrips generally increased with increasing thrips density, but this correlation was steeper in organic than conventional fields. For both Geocoris and Nabis, greater Nabis abundance correlated with reduced probability of detecting thrips DNA; for Nabis this was the only important variable. Nabis is a common intraguild predator of the smaller Geocoris, and is highly cannibalistic, suggesting that predator-predator interference increased with more Nabis present. Complex patterns of thrips predation seemed to result from a dynamic interaction with alternative prey abundance, alongside consistently negative interactions among predators. This provides further evidence that alternative prey and predator interference must be studied in concert to accurately predict the contributions of generalists to biocontrol.

Minimalist revision and description of 403 new species in 11 subfamilies of Costa Rican braconid parasitoid wasps, including host records for 219 species

Three new genera are described: Michener (Proteropinae), Bioalfa (Rogadinae), and Hermosomastax (Rogadinae). Keys are given for the New World genera of the following braconid subfamilies: Agathidinae, Braconinae, Cheloninae, Homolobinae, Hormiinae, Ichneutinae, Macrocentrinae, Orgilinae, Proteropinae, Rhysipolinae, and Rogadinae. In these subfamilies 416 species are described or redescribed. Most of the species have been reared and all but 13 are new to science. A consensus sequence of the COI barcodes possessed by each species is employed to diagnose the species, and this approach is justified in the introduction. Most descriptions consist of a lateral or dorsal image of the holotype, a diagnostic COI consensus barcode, the Barcode Index Number (BIN) code with a link to the Barcode of Life Database (BOLD), and the holotype specimen information required by the International Code of Zoological Nomenclature. The following species are treated and those lacking authorship are newly described here with authorship attributable to Sharkey except for the new species of Macrocentrinae which are by Sharkey & van Achterberg: AGATHIDINAE: Aerophiluspaulmarshi, Mesocoelusdavidsmithi, Neothlipsisbobkulai, Plesiocoelusvanachterbergi, Pneumagathiserythrogastra (Cameron, 1905), Therophilusbobwhartoni, T.donaldquickei, T.gracewoodae, T.maetoi, T.montywoodi, T.penteadodiasae, Zacremnopsbrianbrowni, Z.coatlicue Sharkey, 1990, Zacremnopscressoni (Cameron, 1887), Z.ekchuah Sharkey, 1990, Z.josefernandezi, Zelomorphasarahmeierottoae. BRACONINAE: Braconalejandromarini, B.alejandromasisi, B.alexamasisae, B.andresmarini, B.andrewwalshi, B.anniapicadoae, B.anniemoriceae, B.barryhammeli, B.bernardoespinozai, B.carlossanabriai, B.chanchini, B.christophervallei, B.erasmocoronadoi, B.eugeniephillipsae, B.federicomatarritai, B.frankjoycei, B.gerardovegai, B.germanvegai, B.isidrochaconi, B.jimlewisi, B.josejaramilloi, B.juanjoseoviedoi, B.juliodiazi, B.luzmariaromeroae, B.manuelzumbadoi, B.marialuisariasae, B.mariamartachavarriae, B.mariorivasi, B.melissaespinozae, B.nelsonzamorai, B.nicklaphami, B.ninamasisae, B.oliverwalshi, B.paulamarinae, B.rafamoralesi, B.robertofernandezi, B.rogerblancoi, B.ronaldzunigai, B.sigifredomarini, B.tihisiaboshartae, B.wilberthbrizuelai, Digonogastramontylloydi, D.montywoodi, D.motohasegawai, D.natwheelwrighti, D.nickgrishini. CHELONINAE: Adeliusadrianguadamuzi, A.gauldi Shimbori & Shaw, 2019, A.janzeni Shimbori & Shaw, 2019, Ascogastergloriasihezarae, A.grettelvegae, A.guillermopereirai, A.gustavoecheverrii, A.katyvandusenae, A.luisdiegogomezi, Chelonusalejandrozaldivari, C.gustavogutierrezi, C.gustavoinduni, C.harryramirezi, C.hartmanguidoi, C.hazelcambroneroae, C.iangauldi, C.isidrochaconi, C.janecheverriae, C.jeffmilleri, C.jennyphillipsae, C.jeremydewaardi, C.jessiehillae, C.jesusugaldei, C.jimlewisi, C.jimmilleri, C.jimwhitfieldi, C.johanvalerioi, C.johnburnsi, C.johnnoyesi, C.jorgebaltodanoi, C.jorgehernandezi, C.josealfredohernandezi, C.josefernandeztrianai, C.josehernandezcortesi, C.josemanuelperezi, C.josephinerodriguezae, C.juanmatai, C.junkoshimurae, C.kateperezae, C.luciariosae, C.luzmariaromeroae, C.manuelpereirai, C.manuelzumbadoi, C.marianopereirai, C.maribellealvarezae, C.markmetzi, C.markshawi, C.martajimenezae, C.mayrabonillae, C.meganmiltonae, C.melaniamunozae, C.michaelstroudi, C.michellevanderbankae, C.mingfangi, C.minorcarmonai, C.monikaspringerae, C.moniquegilbertae, C.motohasegawai, C.nataliaivanovae, C.nelsonzamorai, C.normwoodleyi, C.osvaldoespinozai, C.pamelacastilloae, C.paulgoldsteini, C.paulhansoni, C.paulheberti, C.petronariosae, C.ramyamanjunathae, C.randallgarciai, C.rebeccakittelae, C.robertoespinozai, C.robertofernandezi, C.rocioecheverriae, C.rodrigogamezi, C.ronaldzunigai, C.rosibelelizondoae, C.rostermoragai, C.ruthfrancoae, C.scottmilleri, C.scottshawi, C.sergioriosi, C.sigifredomarini, C.stevearonsoni, C.stevestroudi, C.sujeevanratnasinghami, C.sureshnaiki, C.torbjornekremi, C.yeimycedenoae, Leptodrepanaalexisae, L.erasmocoronadoi, L.felipechavarriai, L.freddyquesadai, L.gilbertfuentesi, L.manuelriosi, Phanerotomaalmasolisae, P.alvaroherrerai, P.anacordobae, P.anamariamongeae, P.andydeansi, P.angelagonzalezae, P.angelsolisi, P.barryhammeli, P.bernardoespinozai, P.calixtomoragai, P.carolinacanoae, P.christerhanssoni, P.christhompsoni, P.davesmithi, P.davidduthiei, P.dirksteinkei, P.donquickei, P.duniagarciae, P.duvalierbricenoi, P.eddysanchezi, P.eldarayae, P.eliethcantillanoae, P.jenopappi, Pseudophanerotomaalanflemingi, Ps.albanjimenezi, Ps.alejandromarini, Ps.alexsmithi, Ps.allisonbrownae, Ps.bobrobbinsi. HOMOLOBINAE: Exasticolusjennyphillipsae, E.randallgarciai, E.robertofernandezi, E.sigifredomarini, E.tomlewinsoni. HORMIINAE: Hormiusanamariamongeae, H.angelsolisi, H.anniapicadoae, H.arthurchapmani, H.barryhammeli, H.carmenretanae, H.carloswalkeri, H.cesarsuarezi, H.danbrooksi, H.eddysanchezi, H.erikframstadi, H.georgedavisi, H.grettelvegae, H.gustavoinduni, H.hartmanguidoi, H.hectoraritai, H.hesiquiobenitezi, H.irenecanasae, H.isidrochaconi, H.jaygallegosi, H.jimbeachi, H.jimlewisi, H.joelcracrafti, H.johanvalerioi, H.johnburleyi, H.joncoddingtoni, H.jorgecarvajali, H.juanmatai, H.manuelzumbadoi, H.mercedesfosterae, H.modonnellyae, H.nelsonzamorai, H.pamelacastilloae, H.raycypessi, H.ritacolwellae, H.robcolwelli, H.rogerblancosegurai, H.ronaldzunigai, H.russchapmani, H.virginiaferrisae, H.warrenbrighami, H.willsflowersi. ICHNEUTINAE: Oligoneuruskriskrishtalkai, O.jorgejimenezi, Paroligoneuruselainehoaglandae, P.julianhumphriesi, P.mikeiviei. MACROCENTRINAE: Austrozelejorgecampabadali, A.jorgesoberoni, Dolichozelegravitarsis (Muesebeck, 1938), D.josefernandeztrianai, D.josephinerodriguezae, Hymenochaoniakalevikulli, H.kateperezae, H.katherinebaillieae, H.katherineellisonae, H.katyvandusenae, H.kazumifukunagae, H.keithlangdoni, H.keithwillmotti, H.kenjinishidai, H.kimberleysheldonae, H.krisnorvigae, H.lilianamadrigalae, H.lizlangleyae, Macrocentrusfredsingeri, M.geoffbarnardi, M.gregburtoni, M.gretchendailyae, M.grettelvegae, M.gustavogutierrezi, M.hannahjamesae, M.harisridhari, M.hillaryrosnerae, M.hiroshikidonoi, M.iangauldi, M.jennyphillipsae, M.jesseausubeli, M.jessemaysharkae, M.jimwhitfieldi, M.johnbrowni, M.johnburnsi, M.jonathanfranzeni, M.jonathanrosenbergi, M.jorgebaltodanoi, M.lucianocapelli. ORGILINAE: Orgilusamyrossmanae, O.carrolyoonae, O.christhompsoni, O.christinemcmahonae, O.dianalipscombae, O.ebbenielsoni, O.elizabethpennisiae, O.evertlindquisti, O.genestoermeri, O.jamesriegeri, O.jeanmillerae, O.jeffmilleri, O.jerrypowelli, O.jimtiedjei, O.johnlundbergi, O.johnpipolyi, O.jorgellorentei, O.larryspearsi, O.marlinricei, O.mellissaespinozae, O.mikesmithi, O.normplatnicki, O.peterrauchi, O.richardprimacki, O.sandraberriosae, O.sarahmirandae, O.scottmilleri, O.scottmorii, Stantoniabillalleni, S.brookejarvisae, S.donwilsoni, S.erikabjorstromae, S.garywolfi, S.henrikekmani, S.luismirandai, S.miriamzunzae, S.quentinwheeleri, S.robinkazmierae, S.ruthtifferae. PROTEROPINAE: Hebichneutestricolor Sharkey & Wharton, 1994, Proteropsiangauldi, P.vickifunkae, Michenercharlesi. RHYSIPOLINAE: Pseudorhysipolisluisfonsecai, P. mailyngonzalezaeRhysipolisjulioquirosi. ROGADINAE: Aleiodesadrianaradulovae, A.adrianforsythi, A.agnespeelleae, A.alaneaglei, A.alanflemingi, A.alanhalevii, A.alejandromasisi, A.alessandracallejae, A.alexsmithi, A.alfonsopescadori, A.alisundermieri, A.almasolisae, A.alvarougaldei, A.alvaroumanai, A.angelsolisi, A.annhowdenae, A.bobandersoni, A.carolinagodoyae, A.charlieobrieni, A.davefurthi, A.donwhiteheadi, A.doylemckeyi, A.frankhovorei, A.henryhowdeni, A.inga Shimbori & Shaw, 2020, A.johnchemsaki, A.johnkingsolveri, A.gonodontovorus Shimbori & Shaw, 2020, A.manuelzumbadoi, A.mayrabonillae, A.michelledsouzae, A.mikeiviei, A.normwoodleyi, A.pammitchellae, A.pauljohnsoni, A.rosewarnerae, A.steveashei, A.terryerwini, A.willsflowersi, Bioalfapedroleoni, B.alvarougaldei, B.rodrigogamezi, Choreborogasandydeansi, C.eladiocastroi, C.felipechavarriai, C.frankjoycei, Clinocentrusandywarreni, Cl.angelsolisi, Cystomastaxalexhausmanni, Cy.angelagonzalezae, Cy.ayaigarashiae, Hermosomastaxclavifemorus Quicke sp. nov., Heterogamusdonstonei, Pseudoyeliconesbernsweeneyi, Stiropiusbencrairi, S.berndkerni, S.edgargutierrezi, S.edwilsoni, S.ehakernae, Triraphisbillfreelandi, T.billmclarneyi, T.billripplei, T.bobandersoni, T.bobrobbinsi, T.bradzlotnicki, T.brianbrowni, T.brianlaueri, T.briannestjacquesae, T.camilocamargoi, T.carlosherrerai, T.carolinepalmerae, T.charlesmorrisi, T.chigiybinellae, T.christerhanssoni, T.christhompsoni, T.conniebarlowae, T.craigsimonsi, T.defectus Valerio, 2015, T.danielhubi, T.davidduthiei, T.davidwahli, T.federicomatarritai, T.ferrisjabri, T.mariobozai, T.martindohrni, T.matssegnestami, T.mehrdadhajibabaei, T.ollieflinti, T.tildalauerae, Yeliconesdirksteinkei, Y.markmetzi, Y.monserrathvargasae, Y.tricolor Quicke, 1996. Y.woldai Quicke, 1996.

The following new combinations are proposed: Neothlipsissmithi (Ashmead), new combination for Microdussmithi Ashmead, 1894; Neothlipsispygmaeus (Enderlein), new combination for Microduspygmaeus Enderlein, 1920; Neothlipsisunicinctus (Ashmead), new combination for Microdusunicinctus Ashmead, 1894; Therophilusanomalus (Bortoni and Penteado-Dias) new combination for Plesiocoelusanomalus Bortoni and Penteado-Dias, 2015; Aerophilusareolatus (Bortoni and Penteado-Dias) new combination for Plesiocoelusareolatus Bortoni and Penteado-Dias, 2015; Pneumagathiserythrogastra (Cameron) new combination for Agathiserythrogastra Cameron, 1905. Dolichozelecitreitarsis (Enderlein), new combination for Paniscozelecitreitarsis Enderlein, 1920. Dolichozelefuscivertex (Enderlein) new combination for Paniscozelefuscivertex Enderlein, 1920. Finally, Bassusbrooksi Sharkey, 1998 is synonymized with Agathiserythrogastra Cameron, 1905; Paniscozelegriseipes Enderlein, 1920 is synonymized with Dolichozelekoebelei Viereck, 1911; Paniscozelecarinifrons Enderlein, 1920 is synonymized with Dolichozelefuscivertex (Enderlein, 1920); and Paniscozelenigricauda Enderlein,1920 is synonymized with Dolichozelequaestor (Fabricius, 1804). (originally described as Ophionquaestor Fabricius, 1804).

Endosymbiotic Bacteria Are Prevalent and Diverse in Agricultural Spiders

Maternally inherited bacterial endosymbionts are common in arthropods, but their distribution and prevalence are poorly characterized in many host taxa. Initial surveys have suggested that vertically transmitted symbionts may be particularly common in spiders (Araneae). Here, we used diagnostic PCR and high-throughput sequencing to evaluate symbiont infection in 267 individual spiders representing 14 species (3 families) of agricultural spiders. We found 27 operational taxonomic units (OTUs) that are likely endosymbiotic, including multiple strains of Wolbachia, Rickettsia, and Cardinium, which are all vertically transmitted and frequently associated with reproductive manipulation of arthropod hosts. Additional strains included Rickettsiella, Spiroplasma, Rhabdochlamydia, and a novel Rickettsiales, all of which could range from pathogenic to mutualistic in their effects upon their hosts. Seventy percent of spider species had individuals that tested positive for one or more endosymbiotic OTUs, and specimens frequently contained multiple symbiotic strain types. The most symbiont-rich species, Idionella rugosa, had eight endosymbiotic OTUs, with as many as five present in the same specimen. Individual specimens within infected spider species had a variety of symbiotypes, differing from one another in the presence or absence of symbiotic strains. Our sample included both starved and unstarved specimens, and dominant bacterial OTUs were consistent per host species, regardless of feeding status. We conclude that spiders contain a remarkably diverse symbiotic microbiota. Spiders would be an informative group for investigating endosymbiont population dynamics in time and space, and unstarved specimens collected for other purposes (e.g., food web studies) could be used, with caution, for such investigations.

Generalist predator contributions to the control of Tetranychus urticae in strawberry crops documented by PCR-based gut content analysis

The contribution of generalist insect predators to the control of the two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), an herbivorous pest of many crops, is poorly understood. One of the common insect predators in strawberries is the generalist predatory bug Anthocoris nemorum L. (Hemiptera: Anthocoridae), which has the potential to contribute to the control of pest populations. The feeding of adult A. nemorum on T. urticae was assessed by sampling individuals from an organic strawberry field in Denmark, and using PCR gut content analysis to detect remains of T. urticae within their gut. In the lab, we assessed that the DNA half-life detectability was 21.5 h. Significant numbers of field-collected A. nemorum tested positive for T. urticae prey DNA, with very high numbers in June (62.8%) and August (38.8%). This study presents conclusive evidence that the generalist predator A. nemorum can contribute to the decrease of T. urticae densities in strawberry fields, although the actual contribution in the present study is probably limited because predator populations were relatively low compared to T. urticae. The abundance of T. urticae did not increase significantly during the period of sampling, suggesting that a complex of natural enemies can achieve biological control of T. urticae in protected strawberries.

Revision of the species of Lytopylus from Area de Conservación Guanacaste, northwestern Costa Rica (Hymenoptera, Braconidae, Agathidinae)

Thirty two new species of Lytopylus (Agathidinae) are described with image plates for each species: Lytopylus alejandromasisisp. n., Lytopylus alfredomainierisp. n., Lytopylus anamariamongeaesp. n., Lytopylus angelagonzalezaesp. n., Lytopylus cesarmoraisp. n., Lytopylus eddysanchezisp. n., Lytopylus eliethcantillanoaesp. n., Lytopylus ericchapmanisp. n., Lytopylus gahyunaesp. n., Lytopylus gisukaesp. n., Lytopylus guillermopereiraisp. n., Lytopylus gustavoinduniisp. n., Lytopylus hartmanguidoisp. n., Lytopylus hernanbravoisp. n., Lytopylus hokwonisp. n., Lytopylus ivanniasandovalaesp. n., Lytopylus johanvalerioisp. n., Lytopylus josecortesisp. n., Lytopylus luisgaritaisp. n., Lytopylus mariamartachavarriaesp. n., Lytopylus miguelviquezisp. n., Lytopylus motohasegawaisp. n., Lytopylus okchunaesp. n., Lytopylus pablocobbisp. n., Lytopylus robertofernandezisp. n., Lytopylus rogerblancoisp. n., Lytopylus salvadorlopezisp. n., Lytopylus sangyeonisp. n., Lytopylus sarahmeierottoaesp. n., Lytopylus sergiobermudezisp. n., Lytopylus sigifredomarinisp. n., and Lytopylus youngcheaesp. n. A dichotomous key and a link to an electronic, interactive key are included. All specimens were reared from Lepidoptera larvae collected in Area de Conservación Guanacaste (ACG) and all are associated with ecological information including host caterpillar, collection date, eclosion date, caterpillar food plant, and locality. Neighbor-joining and maximum likelihood analyses of the barcode region of the mitochondrial cytochrome c oxidase subunit I gene (COI DNA barcode) were conducted to aid in species delimitation.

Mitochondrial phylogenomics of Hemiptera reveals adaptive innovations driving the diversification of true bugs

Hemiptera, the largest non-holometabolous order of insects, represents approximately 7% of metazoan diversity. With extraordinary life histories and highly specialized morphological adaptations, hemipterans have exploited diverse habitats and food sources through approximately 300 Myr of evolution. To elucidate the phylogeny and evolutionary history of Hemiptera, we carried out the most comprehensive mitogenomics analysis on the richest taxon sampling to date covering all the suborders and infraorders, including 34 newly sequenced and 94 published mitogenomes. With optimized branch length and sequence heterogeneity, Bayesian analyses using a site-heterogeneous mixture model resolved the higher-level hemipteran phylogeny as (Sternorrhyncha, (Auchenorrhyncha, (Coleorrhyncha, Heteroptera))). Ancestral character state reconstruction and divergence time estimation suggest that the success of true bugs (Heteroptera) is probably due to angiosperm coevolution, but key adaptive innovations (e.g. prognathous mouthpart, predatory behaviour, and haemelytron) facilitated multiple independent shifts among diverse feeding habits and multiple independent colonizations of aquatic habitats.

Overcoming PCR Inhibition During DNA-Based Gut Content Analysis of Ants

Generalist predators play an important role in many terrestrial systems, especially within agricultural settings, and ants (Hymenoptera: Formicidae) often constitute important linkages of these food webs, as they are abundant and influential in these ecosystems. Molecular gut content analysis provides a means of delineating food web linkages of ants based on the presence of prey DNA within their guts. Although this method can provide insight, its use on ants has been limited, potentially due to inhibition when amplifying gut content DNA. We designed a series of experiments to determine those ant organs responsible for inhibition and identified variation in inhibition among three species (Tetramorium caespitum (L.), Solenopsis invicta Buren, and Camponotus floridanus (Buckley)). No body segment, other than the gaster, caused significant inhibition. Following dissection, we determined that within the gaster, the digestive tract and crop cause significant levels of inhibition. We found significant differences in the frequency of inhibition between the three species tested, with inhibition most evident in T. caespitum The most effective method to prevent inhibition before DNA extraction was to exude crop contents and crop structures onto UV-sterilized tissue. However, if extracted samples exhibit inhibition, addition of bovine serum albumin to PCR reagents will overcome this problem. These methods will circumvent gut content inhibition within selected species of ants, thereby allowing more detailed and reliable studies of ant food webs. As little is known about the prevalence of this inhibition in other species, it is recommended that the protocols in this study are used until otherwise shown to be unnecessary.

Revision of Aphelagathis (Hymenoptera, Braconidae, Agathidinae, Agathidini)

One previously described (Aphelagathis verticalis) and ten new species (A. bonnieirwinae, A. ceciliapinedae, A. ericgrisselli, A. genehalli, A. mclintocki, A. mikeirwini, A. rociofernandezae, A. schlingeri, A. stangei, and A. wendymooreae) are included. Aphelagathis is limited to the Nearctic and the northern part of the Neotropics. A. rociofernandezae parasitizes the caterpillars of grass-feeding Hesperiidae (Lepidoptera) as does A. verticalis.

The Nearctic genera of Agathidinae (Hymenoptera: Braconidae) with a phylogenetic analysis, illustrated generic key, and the description of three new genera

The genera of Nearctic Agathidinae are revised based on a phylogenetic analysis of COI and 28S sequence data; 151 ingroup taxa are included. Three new genera are proposed, i.e., Aphelagathis Sharkey n. gen., Pneumagathis Sharkey n. gen. and Gelastagathis Sharkey n. gen.. The enigmatic species Agathis verticalis Cresson is identified and placed in Aphelagathis, Aphelagathis verticalis (Cresson) n. comb., and a neotype for the species is designated. Two species are described, i.e., Gelastagathis grisselli Sharkey n. sp. and G. frosti Sharkey n. sp. Two new combinations are proposed, Bassus spiracularis Muesebeck and Bassus brooksi Sharkey are transferred to Pneumagathis, Pneumagathis spiracularis (Muesebeck) n. comb., Pneumagathis brooksi (Sharkey) n. comb. An illustrated key to the Nearctic genera of Agathidinae is provided.

A revision of the New World species of Cremnops Förster (Hymenoptera: Braconidae: Agathidinae)

The New World species of the genus Cremnops are revised. Thirty-three species of Cremnops are treated; five are described as new, i.e., C. bertae sp. nov., C. cluttsis sp. nov., C. nymphius sp. nov., C. wileycoyotius sp. nov. and C. witkopegasus sp. nov. Six species are synonymized, i.e., Cremnops caribensis Berta, 1998, is synonymized under C. guanicanus Wolcott, 1924; C. nigrosternum (Morrison 1917) is synonymized under C. haematodes (Brullé 1846); C. punctatus Berta, 1998, is synonymized under C. marshi Berta, 1998; C. sharkei Berta, 1998, is synonymized under C. montrealensis (Morrison 1917); C. turrialbae Berta de Fernandez, 1998, is synonymized under C. ferrugineus (Cameron 1887); and C. misionensis Berta, 1987, is synonymized under C. slossonae (Morrison 1917). Cremnops florissanticola is transferred to its original combination Bracon florissanticola Cockerell, 1919, st. rev. Included are a molecular phylogeny, a dichotomous key, links to distribution maps, an electronic interactive key, and images of holotypes.

Linking predator-prey interactions with exposure to a trophically transmitted parasite using PCR-based analyses

Parasite transmission is determined by the rate of contact between a susceptible host and an infective stage and susceptibility to infection given an exposure event. Attempts to measure levels of variation in exposure in natural populations can be especially challenging. The level of exposure to a major class of parasites, trophically transmitted parasites, can be estimated by investigating the host's feeding behaviour. Since the parasites rely on the ingestion of infective intermediate hosts for transmission, the potential for exposure to infection is inherently linked to the definitive host's feeding ecology. Here, we combined epidemiological data and molecular analyses (polymerase chain reaction) of the diet of the definitive host, the white-footed mouse (Peromyscus leucopus), to investigate temporal and individual heterogeneities in exposure to infection. Our results show that the consumption of cricket intermediate hosts accounted for much of the variation in infection; mice that had consumed crickets were four times more likely to become infected than animals that tested negative for cricket DNA. In particular, pregnant female hosts were three times more likely to consume crickets, which corresponded to a threefold increase in infection compared with nonpregnant females. Interestingly, males in breeding condition had a higher rate of infection even though breeding males were just as likely to test positive for cricket consumption as nonbreeding males. These results suggest that while heterogeneity in host diet served as a strong predictor of exposure risk, differential susceptibility to infection may also play a key role, particularly among male hosts. By combining PCR analyses with epidemiological data, we revealed temporal variation in exposure through prey consumption and identified potentially important individual heterogeneities in parasite transmission.

Widespread and persistent invasions of terrestrial habitats coincident with larval feeding behavior transitions during snail-killing fly evolution (Diptera: Sciomyzidae)

BACKGROUND

Transitions in habitats and feeding behaviors were fundamental to the diversification of life on Earth. There is ongoing debate regarding the typical directionality of transitions between aquatic and terrestrial habitats and the mechanisms responsible for the preponderance of terrestrial to aquatic transitions. Snail-killing flies (Diptera: Sciomyzidae) represent an excellent model system to study such transitions because their larvae display a range of feeding behaviors, being predators, parasitoids or saprophages of a variety of mollusks in freshwater, shoreline and dry terrestrial habitats. The remarkable genus Tetanocera (Tetanocerini) occupies five larval feeding groups and all of the habitat types mentioned above. This study has four principal objectives: (i) construct a robust estimate of phylogeny for Tetanocera and Tetanocerini, (ii) estimate the evolutionary transitions in larval feeding behaviors and habitats, (iii) test the monophyly of feeding groups and (iv) identify mechanisms underlying sciomyzid habitat and feeding behavior evolution.

RESULTS

Bayesian inference and maximum likelihood analyses of molecular data provided strong support that the Sciomyzini, Tetanocerini and Tetanocera are monophyletic. However, the monophyly of many behavioral groupings was rejected via phylogenetic constraint analyses. We determined that (i) the ancestral sciomyzid lineage was terrestrial, (ii) there was a single terrestrial to aquatic habitat transition early in the evolution of the Tetanocerini and (iii) there were at least 10 independent aquatic to terrestrial habitat transitions and at least 15 feeding behavior transitions during tetanocerine phylogenesis. The ancestor of Tetanocera was aquatic with five lineages making independent transitions to terrestrial habitats and seven making independent transitions in feeding behaviors.

CONCLUSIONS

The preponderance of aquatic to terrestrial transitions in sciomyzids goes against the trend generally observed across eukaryotes. Damp shoreline habitats are likely transitional where larvae can change habitat but still have similar prey available. Transitioning from aquatic to terrestrial habitats is likely easier than the reverse for sciomyzids because morphological characters associated with air-breathing while under the water's surface are lost rather than gained, and sciomyzids originated and diversified during a general drying period in Earth's history. Our results imply that any animal lineage having aquatic and terrestrial members, respiring the same way in both habitats and having the same type of food available in both habitats could show a similar pattern of multiple independent habitat transitions coincident with changes in behavioral and morphological traits.

Key aspects of the biology of snail-killing Sciomyzidae flies

The biology of snail-killing flies (Diptera: Sciomyzidae) has been studied intensively over the past half-century, especially over the past decade. Today, sciomyzids are biologically the best-known group of higher Diptera. The overarching research objectives are evaluation of sciomyzids as biocontrols of disease-carrying or agriculturally important snails and slugs and as a paradigm group for the study of the evolution of diverse feeding and associated behaviors in flies. We present reviews and analyses of some key features of particular scientific and societal interest, including behavioral and phenological groups; laboratory experimental studies on behavior and development; population biology, bioindicators, ecosystem service provision, and conservation; phylogenetics, molecular studies, and evolutionary biology; and biocontrol.

Novel protein genes in animal mtDNA: a new sex determination system in freshwater mussels (Bivalvia: Unionoida)?

Mitochondrial (mt) function depends critically on optimal interactions between components encoded by mt and nuclear DNAs. mitochondrial DNA (mtDNA) inheritance (SMI) is thought to have evolved in animal species to maintain mito-nuclear complementarity by preventing the spread of selfish mt elements thus typically rendering mtDNA heteroplasmy evolutionarily ephemeral. Here, we show that mtDNA intraorganismal heteroplasmy can have deterministic underpinnings and persist for hundreds of millions of years. We demonstrate that the only exception to SMI in the animal kingdom, that is, the doubly uniparental mtDNA inheritance system in bivalves, with its three-way interactions among egg mt-, sperm mt- and nucleus-encoded gene products, is tightly associated with the maintenance of separate male and female sexes (dioecy) in freshwater mussels. Specifically, this mother-through-daughter and father-through-son mtDNA inheritance system, containing highly differentiated mt genomes, is found in all dioecious freshwater mussel species. Conversely, all hermaphroditic species lack the paternally transmitted mtDNA (=possess SMI) and have heterogeneous macromutations in the recently discovered, novel protein-coding gene (F-orf) in their maternally transmitted mt genomes. Using immunoelectron microscopy, we have localized the F-open reading frame (ORF) protein, likely involved in specifying separate sexes, in mitochondria and in the nucleus. Our results support the hypothesis that proteins coded by the highly divergent maternally and paternally transmitted mt genomes could be directly involved in sex determination in freshwater mussels. Concomitantly, our study demonstrates novel features for animal mt genomes: the existence of additional, lineage-specific, mtDNA-encoded proteins with functional significance and the involvement of mtDNA-encoded proteins in extra-mt functions. Our results open new avenues for the identification, characterization, and functional analyses of ORFs in the intergenic regions, previously defined as "noncoding," found in a large proportion of animal mt genomes.

Mitochondrial phylogenomics of the Bivalvia (Mollusca): searching for the origin and mitogenomic correlates of doubly uniparental inheritance of mtDNA

Background

Doubly uniparental inheritance (DUI) is an atypical system of animal mtDNA inheritance found only in some bivalves. Under DUI, maternally (F genome) and paternally (M genome) transmitted mtDNAs yield two distinct gender-associated mtDNA lineages. The oldest distinct M and F genomes are found in freshwater mussels (order Unionoida). Comparative analyses of unionoid mitochondrial genomes and a robust phylogenetic framework are necessary to elucidate the origin, function and molecular evolutionary consequences of DUI. Herein, F and M genomes from three unionoid species, Venustaconcha ellipsiformis, Pyganodon grandis and Quadrula quadrula have been sequenced. Comparative genomic analyses were carried out on these six genomes along with two F and one M unionoid genomes from GenBank (F and M genomes of Inversidens japanensis and F genome of Lampsilis ornata).

Results

Compared to their unionoid F counterparts, the M genomes contain some unique features including a novel localization of the trnH gene, an inversion of the atp8-trnD genes and a unique 3'coding extension of the cytochrome c oxidase subunit II gene. One or more of these unique M genome features could be causally associated with paternal transmission. Unionoid bivalves are characterized by extreme intraspecific sequence divergences between gender-associated mtDNAs with an average of 50% for V. ellipsiformis, 50% for I. japanensis, 51% for P. grandis and 52% for Q. quadrula (uncorrected amino acid p-distances). Phylogenetic analyses of 12 protein-coding genes from 29 bivalve and five outgroup mt genomes robustly indicate bivalve monophyly and the following branching order within the autolamellibranch bivalves: ((Pteriomorphia, Veneroida) Unionoida).

Conclusion

The basal nature of the Unionoida within the autolamellibranch bivalves and the previously hypothesized single origin of DUI suggest that (1) DUI arose in the ancestral autolamellibranch bivalve lineage and was subsequently lost in multiple descendant lineages and (2) the mitochondrial genome characteristics observed in unionoid bivalves could more closely resemble the DUI ancestral condition. Descriptions and comparisons presented in this paper are fundamental to a more complete understanding regarding the origins and consequences of DUI.

Extreme primary and secondary protein structure variability in the chimeric male-transmitted cytochrome c oxidase subunit II protein in freshwater mussels: evidence for an elevated amino acid substitution rate in the face of domain-specific purifying selection

BACKGROUND

Freshwater unionoidean bivalves, and species representing two marine bivalve orders (Mytiloida and Veneroida), exhibit a mode of mtDNA inheritance involving distinct maternal (F) and paternal (M) transmission routes concomitant with highly divergent gender-associated mtDNA genomes. Additionally, male unionoidean bivalves have a approximately 550 bp 3' coding extension to the cox2 gene (Mcox2e), that is apparently absent from all other metazoan taxa.

RESULTS

Our molecular sequence analyses of MCOX2e indicate that both the primary and secondary structures of the MCOX2e region are evolving much faster than other regions of the F and M COX2-COX1 gene junction. The near N-terminus approximately 2/3 of the MCOX2e region contains an interspecifically variable number of predicted transmembrane helices (TMH) and interhelical loops (IHL) whereas the C-terminus approximately 1/3 is relatively conserved and hydrophilic while containing conserved functional motifs. MCOX2e displays an overall pattern of purifying selection that leads to the preservation of TMH/IHL and C-terminus tail sub-regions. However, 14 amino acid positions in the MCOX2e TMH/IHL sub-region might be targeted by diversifying selection, each representing a site where there exists interspecific variation for the constituent amino acids residing in a TMH or IHL.

CONCLUSION

Our results indicate that Mcox2e is unique to unionoidean bivalves, likely the result of a single insertion event that took place over 65 MYA and that MCOX2e is functional. The predicted TMH number, length and position variability likely stems from substitution-based processes rather than the typically implicated insertion/deletion events. MCOX2e has relatively high rates of primary and secondary structure evolution, with some amino acid residues potentially subjected to site-specific positive selection, yet an overall pattern of purifying selection leading to the preservation of the TMH/IHL and hydrophilic C-terminus tail subregions. The more conserved C-terminus tail (relative to the TMH/IHL sub-region of MCOX2e) is likely biologically active because it contains functional motifs. The rapid evolution of primary and secondary structure in MCOX2e, combined with the action of both positive and purifying selection, provide supporting evidence for the hypothesis that MCOX2e has a novel reproductive function within unionoidean bivalves. All tolled, our data indicate that unionoidean bivalve MCOX2 is the first reported chimeric animal mtDNA-encoded protein.

Reproductive function for a C-terminus extended, male-transmitted cytochrome c oxidase subunit II protein expressed in both spermatozoa and eggs

Our previous study documented expression of a male-transmitted cytochrome c oxidase subunit II protein (MCOX2), with a C-terminus extension (MCOX2e), in unionoidean bivalve testes and sperm mitochondria. Here, we present evidence demonstrating that MCOX2 is seasonally expressed in testis, with a peak shortly before fertilization that is independent of sperm density. MCOX2 is localized to the inner and outer sperm mitochondrial membranes and the MCOX2 antibody's epitope is conserved across >65 million years of evolution. We also demonstrate the presence of male-transmitted mtDNA and season-specific MCOX2 spatial variation in ovaries. We hypothesize that MCOX2 plays a role in reproduction through gamete maturation, fertilization and/or embryogenesis.

Parallel evolution of larval morphology and habitat in the snail-killing fly genus Tetanocera

In this study, we sequenced one nuclear and three mitochondrial DNA loci to construct a robust estimate of phylogeny for all available species of Tetanocera. Character optimizations suggested that aquatic habitat was the ancestral condition for Tetanocera larvae, and that there were at least three parallel transitions to terrestrial habitat, with one reversal. Maximum likelihood analyses of character state transformations showed significant correlations between habitat transitions and changes in four larval morphological characteristics (cuticular pigmentation and three characters associated with the posterior spiracular disc). We provide evidence that phylogenetic niche conservatism has been responsible for the maintenance of aquatic-associated larval morphological character states, and that concerted convergence and/or gene linkage was responsible for parallel morphological changes that were derived in conjunction with habitat transitions. These habitat-morphology associations were consistent with the action of natural selection in facilitating the morphological changes that occurred during parallel aquatic to terrestrial habitat transitions in Tetanocera.

Midge larvae (Diptera: Chironomidae) as indicators of postmortem submersion interval of carcasses in a woodland stream: a preliminary report

Data on colonization of rat carcasses by aquatic insects in riffle and pool areas of a small woodland stream were obtained to elucidate patterns potentially useful for determining the postmortem submersion interval of corpses in flowing water habitats. After 39 days, the carcasses had no visual signs of deterioration in the absence of large scavenging animals. Midge larvae (Diptera: Chironomidae) were the dominant insects colonizing the carcasses. No patterns in numbers of larvae over time were evident, but the diversity of genera increased after 29 days in the riffle. Also, Orthocladius larvae did not begin to colonize the carcasses until after 13 days of submersion in the riffle and after 20 days of submersion in the pool. Although separated only by 20 m, the riffle and pool rats had dissimilar faunal assemblages. This suggests that different indices for determining the postmortem submersion interval of corpses based on midge larvae colonization should be developed for these two habitats. This investigation does not provide replicated data, but does shed light on what may happen to mammalian carcasses placed in a stream at a particular time of the year.