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Beetle Larvae (beetle + larva)
Kinds of Beetle Larvae Selected AbstractsFIRST RECORD OF AN AQUATIC BEETLE LARVA (INSECTA: COLEOPTERA) FROM THE PARSORA FORMATION (PERMO-TRIASSIC), INDIAPALAEONTOLOGY, Issue 6 2007S. C. GHOSH Abstract:, The fossilized larva of an aquatic beetle, Protodytiscus johillaensis gen. et sp. nov., is described from a ferruginous micaceous siltstone bed of the Permo-Triassic Parsora Formation of the South Rewa Gondwana Basin, Madhya Pradesh, India, and its systematic position and ordinal relationships within the coleopterous suborder Adephaga are discussed. Hitherto, the oldest known fossils of the hydradephagan superfamily Dytiscoidea have been Jurassic. The discovery of P. johillaensis extends the range of the Dytiscoidea back to the Permo-Triassic period. [source] Host plant variation in plant-mediated indirect effects: moth boring-induced susceptibility of willows to a specialist leaf beetleECOLOGICAL ENTOMOLOGY, Issue 2 2008SHUNSUKE UTSUMI Abstract 1.,We examined the plant-mediated indirect effects of the stem-boring moth Endoclita excrescens (Lepidoptera: Hepialidae) on the leaf beetle Plagiodera versicolora (Coleoptera: Chrysomelidae) in three willow species, Salix gilgiana, S. eriocarpa, and S. serissaefolia. 2.,When the stem-boring moth larvae damaged stems in the previous year, willows were stimulated to produce vigorously growing lateral shoots on these stems. These new lateral shoots were significantly longer and the upper leaves had significantly higher nitrogen and water content than current-year shoots on unbored stems, although the carbon content and leaf dry mass were not different between lateral and current-year shoots. 3.,In the field, leaf beetle larvae and adults had significantly greater densities on lateral shoots of bored stems than on current-year shoots of unbored stems. A laboratory experiment showed that female beetles had significantly greater mass and fecundity when fed on leaves of newly-emerged lateral shoots. Thus, the stem-boring moth had a positive effect on the temporally and spatially separated leaf beetle by increasing resource availability by inducing compensatory regrowth. 4.,The strength of the indirect effects on the density and performance of the leaf beetle differed among willow species, because there was interspecific variation in host quality and herbivore-induced changes in plant traits. In particular, we suggest that the differences in magnitude of the changes among willow species in shoot length and leaf nitrogen content greatly affected the strength of the plant-regrowth mediated indirect effect, coupled with host-plant preference of the leaf beetle. [source] The lethal effects of gamma irradiation on larvae of the Huhu beetle, Prionoplus reticularis: a potential quarantine treatment for New Zealand export pine treesENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2000Philip J. Lester Abstract Gamma irradiation was investigated as a possible method for disinfestation of huhu beetle larvae, Prionoplus reticularis White, in Pinus radiata D. Don. Larvae of four representative size classes were irradiated at six doses, and the lethal dose (LD99) calculated from mortality data 3 days and 10 days post treatment. All larval size classes showed a similar sensitivity to gamma irradiation and required 3677 Gray (Gy) and 2476 Gy for a LD99 3 and 10 days post-treatment, respectively. The penetration of gamma irradiation into pine wood was found to be lowest in freshly cut logs, and decreased linearly at a rate of 0.698 Gy mm,1 of wood. The penetration was greatest in wood that had been stored for 2 years, and decreased 0.512 Gy mm,1 of wood. These results are likely to be correlated with wood moisture content. Gamma irradiation appears to be a potential alternative method to fumigation for quarantine treatment of P. reticularis. [source] Soluble carbohydrates in the nutrition of house longhorn beetle larvae, Hylotrupes bajulus (L.) (Col., Cerambycidae): from living sapwood to faecesJOURNAL OF APPLIED ENTOMOLOGY, Issue 9 2002W. Höll Living sapwood contains high amounts of sucrose, glucose, fructose and starch. These carbohydrates seem to be hydrolysed and metabolized during the production of the sapwood blocks. The faeces contain carbohydrates which are not present either in living sapwood or in the sapwood blocks: xylose and an oligosaccharide of uncertain composition. This oligosaccharide is the dominant water-soluble carbohydrate in the faeces. In contrast to living sapwood and sapwood blocks, the faeces contain considerable amounts of soluble ,-glucans. The results show that the composition and the amounts of carbohydrates differ significantly from that in the sapwood blocks (fodder for the larvae). The ,-glucans (starch) present in the wood are not significantly utilized by the larvae. Regarding soluble carbohydrates, diet wood has only little in common with the living wood of the standing tree. [source] Targeted sugar provision promotes parasitism of the cereal leaf beetle Oulema melanopusAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 1 2010Edward W. Evans 1Parasitoids may often lack access to sugar (e.g. floral nectar) in agricultural settings. Strategically timed spraying of host plants with sugar solution may provide one means of enhancing parasitism at the same time as minimizing nontarget effects (e.g. benefiting the pest itself). 2Sucrose was sprayed in wheat fields of northern Utah (U.S.A.) to assess the effects on parasitism of the cereal leaf beetle Oulema melanopus by the larval parasitoid Tetrastichus julis. 3Early-season sugar provisioning, when larvae of the pest were first hatching and parasitoid adults were newly emerged, did not affect the numbers of cereal leaf beetle larvae that matured in treated plots but increased parasitism rates of beetle larvae by four-fold in 2006 and by seven-fold in 2007. 4No net influx of adult parasitoids into plots was detected after the application of sugar. Locally-emerging parasitoids may have spent less time searching for their own food needs versus hosts. A laboratory experiment also confirmed that access to sucrose significantly increased parasitoid longevity. 5The field experimental results obtained demonstrate that applications of sugar, implemented to target a key time of the growing season when benefits are maximized for parasitoids and minimized for their hosts, can strongly promote parasitism of the cereal leaf beetle in wheat fields. [source] Larval chaetotaxy of Coleoptera (Insecta) as a tool for evolutionary research and systematics: less confusion, more clarityJOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 2 2007A. Y. Solodovnikov Abstract Chaetotaxy of beetle larvae is a significant source of characters for descriptive and phylogenetic aspects of systematics of this largest group of animals of comparable age. Survey of the mostly modern systematic literature employing larval chaetotaxy in Coleoptera reveals, however, that contrary to some general claims for the utility of this character set, use of larval chaetotaxy is rather limited. This is mostly because researchers find working with larval chaetotaxy difficult and time consuming. Factors that make exploration of chaetotaxy so cumbersome are methodologically analysed here and divided into two categories: intrinsic and operational. It is revealed that the most dangerous of them are operational, which arise from the multiplication of inconsistencies coming from different levels of comparative morphological research. As a result, ill-defined assessments of larval chaetotaxy may bring more confusion than clarity to the systematics of beetles, especially to its phylogenetic component which is intuitively avoided by researchers who refuse to use chaetotaxy. This paper attempts to scrutinize the sources of these inconsistencies undermining studies of larval chaetotaxy in hope of eliminating them from present and future systematic studies of Coleoptera. Some methodological issues raised here are also applicable to adult Coleoptera, to other insects and invertebrates, or to the proper ways of exploring the comparative morphology of living organisms, underlying evolutionary and systematic research. Zusammenfassung Die larvale Chaetotaxie von Käfern stellt wichtige Merkmale für deskriptive und phylogenetische Aspekte der Systematik dieser größten Tiergruppe zur Verfügung. Die Auswertung überwiegend moderner systematischer Schriften, in denen larvale Chaetotaxie bei Käfern angewendet wird, hat jedoch ergeben, dass, entgegen der allgemeinen Behauptung der Nützlichkeit dieses Merkmalskomplexes, dessen tatsächliche Anwendung recht begrenzt bleibt. Dies rührt haupsächlich daher, dass larvale Chaetotaxie als schwierig und zeitraubend angesehen wird. Die Faktoren, welche chaetotaxonomische Untersuchungen erschweren, werden hier methodologisch analysiert und in zwei Gruppen unterteilt: intrinsische Faktoren und operationale Faktoren. Es wird aufgezeigt, dass die operationalen Faktoren die größten Gefahren mit sich bringen, bedingt durch die Multiplikation widersprüchlicher Befunde von verschiedenen Ebenen vergleichend-morphologischer Forschung. Als Resultat können fehlgeleitete Bewertungen larvaler Chaetotaxie mehr zur Verwirrung als zur Aufklärung der Käfersystematik beitragen. Dies trifft insbesondere auf die phylogenetische Komponente der Systematik zu, die von Forschern, welche die Verwendung der Chaetotaxie ablehnen, intuitiv gemieden wird. Die vorliegende Arbeit versucht, die Quellen der widersprüchlichen Befunde zu ergründen, welche den Wert von Untersuchungen zur larvalen Chaetotaxie untergraben, sodass sie in aktuellen und zukünftigen systematisch-coleopterologischen Untersuchungen vermieden werden können. Einige der hier erörterten methodologischen Gesichtspunkte sind auch anwendbar auf adulte Käfer, andere Insekten und Wirbellose oder allgemein auf die korrekte Vorgehensweise bei der Erforschung der vergleichenden Morphologie lebender Organismen, die der Systematik und Evolutionsforschung zugrunde liegen. [source] Chlorpyrifos residue levels in avian food items following applications of a commercial EC formulation to alfalfa and citrusPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 11 2003Larry W Brewer Abstract Two 10-day field residue studies were conducted to measure the amount of chlorpyrifos residue found in typical avian food following applications of a commercial 480 g liter,1 EC (Lorsban® 4E) at 1.1 kg AI ha,1 (1 lb AI acre,1) to alfalfa and at 2.3 kg AI ha,1 (2.0 lb AI acre,1) to citrus. Avian food items used in these studies included: crickets (Acheta domestica (L)), earthworms (Lumbricus terrestris L), darkling ground beetle larvae (Tenebrio molitor L), seed heads (Triticum sp), and naturally occurring flying and ground-dwelling insects. The studies incorporated a design involving three main study plots placed within larger treated areas of an alfalfa crop and a mature orange grove. The three main study plots represented three replications and each contained four sub-plots. One sub-plot, on each study plot, was sampled on day 0 (2-h post-application), day 1, day 5 and day 10 post-application. Chlorpyrifos residues were present in all avian food sampled following the application; however, residue levels were lower than estimated residue values typically used by the US EPA to establish expected environmental concentration (EEC) used in screening assessments of risk to terrestrial wildlife. Copyright © 2003 Society of Chemical Industry [source] Can herbivore-induced plant volatiles inform predatory insect about the most suitable stage of its prey?PHYSIOLOGICAL ENTOMOLOGY, Issue 4 2009KINUYO YONEYA Abstract. The leaf beetle Plagiodera versicolora (Coleoptera: Chrysomelidae) is a specialist herbivore, all of whose mobile stages feed on the leaves of salicaceous plants. Both the larval and adult stages of the ladybird Aiolocaria hexaspilota (Coleoptera: Coccinellidae) are dominant natural enemies of the larvae of the leaf beetle. To clarify the role of plant volatiles in prey-finding behaviour of A. hexaspilota, the olfactory responses of the ladybird in a Y-tube olfactometer are studied. The ladybird adults show no preference for willow plants Salix eriocarpa that are infested by leaf beetle adults (nonprey) over that for intact plants but move more to the willow plants infested by leaf beetle larvae (prey) than to intact plants. Moreover, ladybird larvae show no preference for willow plants infested by leaf beetle larvae or adults over intact plants. Using gas chromatography-mass spectrometry, six volatile compounds are released in larger amounts in the headspace of willow plants infested by leaf beetle larvae than in the headspace of willow plants infested by leaf beetle adults. In addition, the total amount of volatiles emitted from willow plants that are either intact or infested by leaf beetle adults is much smaller than that from willow plants infested by leaf beetle larvae. These results indicate that volatiles from S. eriocarpa infested by P. versicolora inform A. hexaspilota adults about the presence of the most suitable stage of their prey, whereas A. hexaspilota larvae do not use such information. [source] The ontogeny of handling hard-to-process food in wild brown capuchins (Cebus apella apella): evidence from foraging on the fruit of Maximiliana maripaAMERICAN JOURNAL OF PRIMATOLOGY, Issue 11 2010Noëlle Gunst Abstract We examined age-related differences in wild brown capuchins' foraging efficiency and the food-processing behaviors directed toward maripa palm fruit (Maximiliana maripa). A detailed comparison of the different foraging techniques showed that plucking the fruit from the infructescence constituted the main difficulty of this task. Foraging efficiency tended to increase with age, with a threshold at which sufficient strength allowed immatures by the age of three to reach adult-level efficiency. Youngsters spent more time than older individuals browsing the infructescence and pulling the fruit in an attempt to harvest it. Infants tried to compensate for their inability to pluck fruit by adopting alternative strategies but with low payback, such as gnawing unplucked fruit and opportunistically scrounging others' partially processed food. Although around 2 years of age, young capuchins exhibited all of the behaviors used by adults, they did not reach adult-level proficiency at feeding on maripa until about 3 years (older juveniles). We compared this developmental pattern with that of extractive foraging on beetle larvae (Myelobia sp.) hidden in bamboo stalks, a more difficult food for these monkeys [Gunst N, Boinski S, Fragaszy DM. Behaviour 145:195,229, 2008]. For maripa, the challenge was mainly physical (plucking the fruit) once a tree was encountered, whereas for larvae, the challenge was primarily perceptual (locating the hidden larvae). For both foods, capuchins practice for years before achieving adult-level foraging competence, and the timeline is extended for larvae foraging (until 6 years) compared with maripa (3 years). The differing combinations of opportunities and challenges for learning to forage on these different foods illustrate how young generalist foragers (i.e. exploiting a large number of animal and plant species) may compensate for their low efficiency in extractive foraging tasks by showing earlier competence in processing less difficult but nutritious foods, such as maripa fruit. Am. J. Primatol. 72:960,973, 2010. © 2010 Wiley-Liss, Inc. [source] Spatial density-dependent parasitism and specificity in the robber fly Mallophora ruficauda (Diptera: Asilidae)AUSTRAL ECOLOGY, Issue 1 2010MARCELA K. CASTELO Abstract The density-dependence in parasitism by the robber fly Mallophora ruficauda (Diptera: Asilidae) on scarab beetle larvae (Coleoptera: Scarabaeidae) populations was studied in the present research. Mallophora ruficauda is a pestiferous species common in the open grasslands of the Pampas region of South America. Adults are predators of insects and larvae are solitary parasitoids of third instar larvae of several species of scarab beetle (Coleoptera: Scarabaeidae). In contrast with most studied host-parasitoid interactions, host searching by M. ruficauda is carried out by both larvae and adults. Typically, robber fly females lay eggs on tall grasses from where larvae drop to the ground, and attack hosts which are buried in the soil. We carried out our study at two spatial scales close to 14 apiaries located in the provinces of Buenos Aires and Entre Ríos (Argentina). We found that parasitism is density-independent at the larger spatial scale and inversely density-dependent at the smaller one. We also found that M. ruficauda selects Cyclocephala signaticollis among several scarab beetle species. Specificity is observed both at large and small spatial scales. We discuss the implications of both host specificity and host searching behaviour on the observed parasitism patterns. [source] How to Spoil the Taste of Insect Prey?CHEMBIOCHEM, Issue 12 2010A Novel Feeding Deterrent against Ants Released by Larvae of the Alder Leaf Beetle, Agelastica alni Abstract Chemical defense of leaf beetle larvae (Chrysomelidae) against enemies is provided by secretions containing a wide range of deterrent compounds or by unpalatable hemolymph constituents. Here we report a new, very strong feeding deterrent against ants released by larvae of the alder leaf beetle Agelastica alni when attacked. The larvae release a defensive fluid from openings of pairwise, dorsolaterally located tubercles on the first to the eighth abdominal segments. The fluid, consisting of hemolymph and probably a glandular cell secretion, has previously been shown to contain a very stable, non-volatile feeding deterrent. The major deterrent component was isolated by repeated HPLC separation and analyzed by NMR and MS. The compound proved to be ,- L -glutamyl- L -2-furylalanine (1), a novel dipeptide containing the unusual amino acid L -2-furylalanine. This amino acid, although synthetically well known, has not previously been reported from natural sources. The absolute configuration of the natural compound was elucidated by enantioselective gas chromatography after derivatization. The structure of the dipeptide was verified by the synthesis of several isomeric dipeptides. In bioassays a concentration of 1 ,g,,L,1 was sufficient to deter polyphagous Myrmica rubra ants from feeding. 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