\u3ci\u3eGomphus Spicatus\u3c/i\u3e (Odonata: Gomphidae) Rediscovered in Illinois and \u3ci\u3eLibellula Semifasciata\u3c/i\u3e (Odonata: Libellulidae) Recorded Near Wisconsin

(excerpt) Gomphus spicatus Hagen (Odonata: Gomphidae), commonly called dusky clubtail, is a common and widely distributed dragonfly in a variety of ponds, lakes, and slow streams throughout its range in the north-eastern and northcentral United States and adjacent areas of southern Canada (Donnelly 2004)

How Did E. M. Walker Measure the Length of the Labium of Nymphs of \u3ci\u3eAeshna\u3c/i\u3e and \u3ci\u3eRhionaeschna\u3c/i\u3e (Odonata: Aeshnidae)?

The exhaustive studies of nymphs of Aeshna Fabricius and Rhionaeschna Förster by E. M. Walker (1912-1958) have long guided the taxonomy of these groups and formed the basis for keys still in use today. However, uncertainty about how he measured the length of the labium, including the varied terminology he used over the duration of his career concerning this structure, has led to confusion about application of his taxonomic recommendations. We recalculated ratios of the maximum width/length [W(max)/L] by measuring the illustration dimensions of folded labia and prementums in publications throughout his career and compared these data with the ratios he stated in those publications and with ratios derived from measurements of specimens in our collections. Our results show that from 1912 to 1941, Walker restricted length measurement to the prementum proper (which he called the “mentum of the labium”), exclusive of the ventrally visible portion of the postmental hinge. However, in 1941 he reported ratios from length measurements done two ways, excluding the postmental hinge in his description of the nymph of A. verticalis Hagen, but including the hinge in his description of the nymph of A. septentrionalis Burmeister (Whitehouse 1941). In Walker’s most recent and influential work (1958), he included the postmental hinge in labium length measurements of nine species, but restricted length measurements to the prementum for five others. He was consistent with the use of terms, using both “folded labium” by which he meant the prementum plus the postmental hinge, and “prementum” by which he meant only that structure. However, Walker’s descriptions of the labium in his latest work are buried in long, frequently punctuated sentences that for most species include the terms “folded labium” and “prementum” in the same sentence, so careful reading is required to know which term is intended in the width/length ratio. Width/length ratios we each calculated independently were invariably similar for a given species and were usually similar to Walker’s stated ratio for that species. These similarities affirm our conclusion that while labium measurements must be done with care, they are closely repeatable among workers and will consistently lead to correct determinations in properly designed couplets of dichotomous keys to these genera. We recommend measuring the length of the prementum proper in future studies of these genera when labium ratios are calculated because we found less variability in those cases than when the measurements included the postmental hinge. An approximate conversion between the two methods of calculating W(max)/L ratios can be made as follows: ratio calculated when the length of the prementum excluding the postmental hinge is used x 0.88 is approximately equal to the ratio when the postmental hinge is included for species of Aeshna and Rhionaeschna in North America

Seasonal Drift of \u3ci\u3eLethocerus Americanus\u3c/i\u3e (Hemiptera: Belostomatidae) in a Lake Superior Tributary

Drifting adult Lethocerus americanus were captured and retained by an inclined-screen smolt trap during two field seasons in the Bois Brule River, Wisconsin. Seasonal peaks of drift occurred in spring for 4 weeks following ice out and in autumn for 7 -8 weeks from mid-September through ice formation, and may have continued under ice cover when our gear was not operated. These findings are consistent with the known movement pattern of these insects to fly from lentic habitats to streams to overwinter but also suggest longitudinal movement via drift, perhaps to reach specific overwintering sites. Drift was significantly correlated with declining water temperatures in 1989 but not in 1990. Most drift occurred at water temperatures less than 12°C. There was no correlation between drift and river discharge. Drift rates were consistently low with a maximum by volume of 9 animals per 10,000 m3

Efficacy of Morphological Characters for Distinguishing Nymphs of \u3ci\u3eEpitheca Cynosura\u3c/i\u3e and \u3ci\u3eEpitheca Spinigera\u3c/i\u3e (Odonata: Corduliidae) in Wisconsin

Attempts to distinguish exuviae and last-instar nymphs of Epitheca cynosura (Say) and Epitheca spinigera (Selys) (Odonata: Corduliidae) using lateral spine characters have proven to be unreliable, and recent use of setae counts on only one side of the prementum or one labial palp have led to confusion because these structures often hold unequal numbers of setae on the two sides of the same specimen. Based on exuviae of 67 reared E. cynosura and 55 reared E. spinigera from lakes throughout Wisconsin, we tested the efficacy of previously used character states for distinguishing these species and searched for new characters to improve the reliability of regional keys. The most reliable diagnostic character was the combined number of setae on both sides of the prementum and on both labial palps (≤ 35 – E. cynosura; ≥ 36 – E. spinigera), which correctly determined 96% of our specimens. For the small percentage of specimens that lie in the region of overlap in total setae number, we found that total exuviae length, cerci ÷ epiproct ratios of females, tubercle distance ÷ epiproct ratios of males, and the shape of the dorsal hook on segment 8 could be used to strengthen determinations

Récepteurs nicotiniques neuronaux d'insectes et insecticides : Caractérisation de facteurs intracellulaires impliqués dans la modulation de l'efficacité des néonicotinoides (Thèse de Doctorat d'Université)

L\u27utilisation des produitq phytosanitaires est indispensable pour augmenter la qualité des productions agricoles. Cependant les directives européennes et nationales préconisent une réduction de 50% de leur utilisation pour préserver l\u27environnement et limiter les effets secondaires sur les organismes non-cibles. Dans cette optique, et pour optimiser l\u27efficacité de ces produits tout en diminuant leur dose d\u27utilisation, il est nécessaire de caractériser les facteurs cellulaires et moléculaires impliqués dans la modulation de l\u27effet insecticide de ces composés sur leurs cibles membranaires. Parmi les insecticides les plus utilisés en agriculture, les néonicotinoïdes occupent une place importante sur le marché. Ils ont pour cible les récepteurs à l’acétylcholine de type nicotinique (nAChRs) du système nerveux central des insectes. Chez la blatte Periplaneta americana, des cellules neurosecrétrices identifiées, les neurones DUM, expriment deux sous-types de nAChRs, (nAChR1 et nAChR2). Alors que nAChR1 est sensible à l’imidaclopride (IMI), néonicotinoïde de première génération, cet insecticide ne présente aucun effet sur nAChR2. Afin d’obtenir une meilleure compréhension du mode d’action de ces insecticides sur des nAChRs insensibles, l’objectif de ce travail de recherche a été de caractériser du point de vue électro-pharmacologique les facteurs cellulaires et moléculaires qui influencent l’efficacité d’un insecticide néonicotinoïde de seconde génération, l’acétamipride (ACT) qui présente des caractéristiques chimiques différentes de l’IMI. Grâce à la technique électrophysiologique du patch-clamp, dans des conditions de potentiel imposé, il a été possible de démontrer que l’effet de l’ACT sur nAChR2 dépend du potentiel de membrane. Une dépolarisation de la membrane augmente légèrement la sensibilité de nAChR2 pour l’ACT alors qu’une hyper polarisation produit un effet inverse significatif. Dans les deux cas, l’implication du calcium intracellulaire a été démontrée. Pour des potentiels plus positifs que le potentiel de membrane (i.e., -50 mV), l’inhibition de l’influx calcique via l’activation des canaux calci ques à haut seuil d’activation (High Voltage-Activated) par le chlorure de cadmium et l’ω-conotoxine GVIA augmente la sensibilité de nAChR2 pour l’ACT. Des effets similaires sont obtenus pour des potentiels de membrane plus hyperpolarisés lorsque la perméabilité calcique est inhibée par le LOE 908, un inhibiteur des canaux TRPγ. Dans ce dernier cas, l’utilisation d’o utils pharmacologiques spécifiques (e.g., forskoline, W7) a permis de révéler que la voie de signalisation intracellulaire AMPcyclique/adenylate cyclase est impliquée dans la modulation de l’efficacité de l’ACT sur nAChR2. Enfin, des mesures de la résistance membran aire, réalisées en parallèle dans des conditions de courant imposé, indiquent que l’état conformationnel des nAChR2 joue également un rôle important dans la modulation de l’efficacité de l’ACT. L’ensemble de ces résultats qui ont permis d’identifier de nouveaux facteurs cellulaires et moléculaires impliqués dans la modulation de l’efficacité d’un néonicotinoide, l’ACT ouvrent des perspectives très intéressantes pour optimiser l’efficacité d’un traitement insecticide

Beaches, People, and Change: A Political Ecology of Rockaway Beach after Hurricane Sandy

This dissertation uses restoration practices of Rockaway beach post-Hurricane Sandy as a lens to investigate tensions between nature and society on urban coasts. By focusing on this New York City beach, this dissertation aims to examine the interaction between the beach, residents, city and federal agencies, and local environmental grassroots stewards in their response to coastal flooding and erosion. This is an ethnographic case study of Rockaway Beach during the two years (October 2012-October 2014) following Hurricane Sandy. This case study is based on secondary data analysis of interviews with 52 key informants, field-notes from participant observation at community and stewardship events, and archival research. This dissertation begins with a critical environmental history of Rockaway. From there, the dissertation examines the steward\u27s practices as a counterpoint to the federal and city agency official approaches in a time of increasing awareness and concern over sea-level rise and coastal erosion. The dissertation examines the conflicts that arise in this unique urban beach over expertise, property, nature, and development. And it concludes with considerations of procedural, distributive, and interactional justice and equity for urban beaches. The dissertation makes the case that beaches should not be managed as separate from people or nearby communities and that such management must be sensitive to issues of equity and power

First Records for \u3ci\u3eAeshna Sitchensis\u3c/i\u3e (Odonata: Aeshnidae) and \u3ci\u3eEnallagma Clausum\u3c/i\u3e (Odonata: Coenagrionidae), and a Northwestern Record for the State-Endangered \u3ci\u3eSomatochlora Incurvata\u3c/i\u3e (Odonata: Corduliidae) in Wisconsin

While surveying for Odonata in coastal peatlands and associated shoreline areas adjacent to Lake Superior in Wisconsin, we documented populations of two new state record species, the zig-zag darner (Aeshna sitchensis Hagen) and the alkali bluet (Enallagma clausum Morse). We also located a robust population of the state-endangered incurvate emerald (Somatochlora incurvata Walker) at the northwestern edge of the known range of this species. Adults and exuviae of A. sitchensis and S. incurvata were found at an insular fen on Stockton Island, Ashland County, within the Apostle Islands National Lakeshore (AINL). Breeding of both species had occurred in areas of the fen where small pools had dried by summer. Additionally, a single adult male A. sitchensis was collected in the City of Superior in Douglas County. Adult E. clausum were found at two sites: on the Lake Superior beach near the mouth of the Sand River within the AINL in Bayfield County, and along the northeast shore of Allouez Bay in the City of Superior in Douglas County