Search results for "pupa"
showing 10 items of 72 documents
Passive sinking into the snow as possible survival strategy during the off-host stage in an insect ectoparasite
2015
Abiotic and biotic factors determine success or failure of individual organisms, populations and species. The early life stages are often the most vulnerable to heavy mortality due to environmental conditions. The deer ked (Lipoptena cervi Linnaeus, 1758) is an invasive insect ectoparasite of cervids that spends an important period of the life cycle outside host as immobile pupa. During winter, dark-coloured pupae drop off the host onto the snow, where they are exposed to environmental temperature variation and predation as long as the new snowfall provides shelter against these mortality factors. The other possible option is to passively sink into the snow, which is aided by morphology of …
Direct and correlated responses to bi-directional selection on pre-adult development time in Drosophila montana.
2019
Selection experiments offer an efficient way to study the evolvability of traits that play an important role in insects’ reproduction and/or survival and to trace correlations and trade-offs between them. We have exercised bi-directional selection on Drosophila montana flies’ pre-adult development time under constant light and temperature conditions for 10 generations and traced the indirect effects of this selection on females’ diapause induction under different day lengths, as well as on the body weight and cold tolerance of both sexes. Overall, selection was successful towards slow, but not towards fast development. However, all fast selection line replicates showed at the end of selecti…
Dacnusa cicerina (Hymenoptera: Braconidae: Alysiinae), A New Species of Endoparasitoid of Liriomyza cicerina (Diptera: Agromyzidae)
2008
Abstract The larvae, pupa, adults, and venom apparatus of Dacnusa cicerina sp. n., an endoparasitoid of Liriomyza cicerina (Rondani), found on Cicer arietinum Linnaeus in Spain, are described, illustrated, and compared with those of allied species. The mature larva of Eurytoma sp., possibly a hyperparasitoid of D. cicerina, also is described, illustrated, and compared with those of allied species. Keys to discriminate adults are provided and morphological structures of phylogenetic value are discussed. The adults of D. cicerina are similar to those of Dacnusa rodriguezi Docavo & Tormos (1997). The immature larvae are similar to those of Dacnusa areolaris (Nees) and Dacnusa dryas (Nixon), an…
From deception to frankness: Benefits of ontogenetic shift in the anti-predator strategy of alder moth Acronicta alni larvae
2014
Abstract Animals can avoid prédation by masquerading as objects that are not food to their predators. Alder moth Acronicta alni larvae go through an impressive ontogenetic change from masquerade to highly conspicuous appearance: early larval stages resemble bird droppings but in the last instar the larval coloration changes into striking yellow-and-black stripes. We hypothesized that such a change may be driven by differential prédation favoring dissimilar anti-predator strategies in different life stages. We show with a series of laboratory assays that larvae are distasteful to birds regardless of their developmental stage, suggesting that ontogenetic color change is not driven by the diff…
First Descriptions of Larva and Pupa of
2019
In this paper, the mature larva and pupa of Bagous claudicans are described and illustrated for the first time. Measurements of younger larval instars are also given. The biology of the species is discussed in association with larval morphology and feeding habits. Overall larval and pupal morphological characters of the genus Bagous are presented. Confirmation of the larva identification as Bagous claudicans species was conducted by cytochrome oxidase I (COI) sequencing. DNA barcoding was useful for specimen identification of larval stages. The systematic position of the species within the Bagous collignensis-group, based on morphological and molecular results, is also discussed.
Vertical transmission of naturally occurring Bunyamwera and insect-specific flavivirus infections in mosquitoes from islands and mainland shores of L…
2018
Background Many arboviruses transmitted by mosquitoes have been implicated as causative agents of both human and animal illnesses in East Africa. Although epidemics of arboviral emerging infectious diseases have risen in frequency in recent years, the extent to which mosquitoes maintain pathogens in circulation during inter-epidemic periods is still poorly understood. This study aimed to investigate whether arboviruses may be maintained by vertical transmission via immature life stages of different mosquito vector species. Methodology We collected immature mosquitoes (egg, larva, pupa) on the shores and islands of Lake Baringo and Lake Victoria in western Kenya and reared them to adults. Mo…
Integration of complex larval chemosensory organs into the adult nervous system ofDrosophila
2003
The sense organs of adult Drosophila, and holometabolous insects in general, derive essentially from imaginal discs and hence are adult specific. Experimental evidence presented here, however, suggests a different developmental design for the three largely gustatory sense organs located along the pharynx. In a comprehensive cellular analysis, we show that the posteriormost of the three organs derives directly from a similar larval organ and that the two other organs arise by splitting of a second larval organ. Interestingly, these two larval organs persist despite extensive reorganization of the pharynx. Thus, most of the neurons of the three adult organs are surviving larval neurons. Howev…
Pupu sēklgrauža (Bruchus rufimanus) bioloģija, ekoloģija un to ietekmējošie faktori lauka pupas (Vicia faba) sējumos
2018
Palielinoties lauka pupas sējas platībām gan Eiropas gan Latvijas teritorijas ietvaros, palielinās arī ar tām saistīto kaitēkļu apdzīvotās vietas. Pupu sēklgrauzis (Bruchus rufimanus Boh.) ir zināms lauka pupas kaitēklis, kura kāpurs barojas ar tās sēklām auga jaunajās pākstīs. Daļa sēklgrauža populācijas pārziemo sēklās sēklu glabātavās. Pētījuma mērķis ir izprast pupu sēklgrauža attīstības bioloģiju un ekoloģiju un to ietekmējošos faktorus. Pētījums veikts septiņos lauka pupas sējumos 2017. gada veģetācijas sezonā. Sēklgrauža ekoloģijas izprašanai veica imago uzskaites lauka pupās, olu uzskaites uz jaunajām pākstīm, pākstu paraugu un sējas materiāla analīzi. Pākstu paraugus analizēja pēc …
A previously unreported numph cocoon of Alphasida puncticollis on the islet of Lampione (Sicilian Channel) (Coleoptera Tenebrionidae).
2010
In this paper we present an unusual case of cocoons produced by larvae of Tenebrionid Alphasida (Glabrasida) puncticollis (Solier, 1836), which has been observed on the islet of Lampione (Sicilian Channel). Pupal cocoons have never been recorded for species belonging to this genus, and their occurrence results rarely documented within the family Tenebrionidae. Some ecological implications are discussed.
Pathogenicity bioassays of isolates of Beauveria bassiana on Rhynchophorus ferrugineus
2012
BACKGROUND:The control ofRhynchophorusferrugineus (Olivier), themainpalmpest in theMediterraneanBasin, is problematic because of its biology and the current restrictions inmany European countries on the use of chemical insecticides in urban areas. Entomopathogenic fungi have been studied as potential biological control agents, but information on their natural incidence is limited. Strains of Beauveria bassiana (Balsamo) Vuillemin were isolated from symptomatic insects collected on dead palms, and their pathogenicity against different instars of R. ferrugineus was evaluated in the laboratory. RESULTS: The overall percentage of infected insects found in Canary palms was 7%. In laboratory bioa…