Search results for "Nymph"
showing 10 items of 81 documents
Spatial data of Ixodes ricinus instar abundance and nymph pathogen prevalence, Scandinavia, 2016-2017.
2020
ticks carry pathogens that can cause disease in both animals and humans, and there is a need to monitor the distribution and abundance of ticks and the pathogens they carry to pinpoint potential high risk areas for tick-borne disease transmission. In a joint Scandinavian study, we measured Ixodes ricinus instar abundance at 159 sites in southern Scandinavia in August-September, 2016, and collected 29,440 tick nymphs at 50 of these sites. We additionally measured abundance at 30 sites in August-September, 2017. We tested the 29,440 tick nymphs in pools of 10 in a Fluidigm real-time PCR chip to screen for 17 different tick-associated pathogens, 2 pathogen groups and 3 tick species. We present…
Fishless-stream mayflies express behavioural flexibility in response to predatory fish
1996
The fish avoidance behaviour of nymphs of the grazing mayfly Baetis rhodani (Ephemerop- tera) was examined. The nymphs originated from a fishless stream. To study their responses to the addition of predator cues, nymphs were exposed to (1) chemical cues from a caged fish, or (2) a freely moving diurnal fish (European minnow, Phoxinus phoxinus). The nymphs immediately increased their refuge use when exposed to a live fish, whereas chemical cues alone did not cause any avoidance responses. In a second experiment, the eVects of (1) fish chemicals and (2) a fish model plus fish chemicals on the diel refuge use patterns of Baetis nymphs were examined. In the presence of a fish model, more nymphs…
Temporal variation in reproductive allocation in a shield bug Elasmostethus interstinctus
1996
We investigated changes in the reproductive output and the effect of female phenotype on reproductive parameters in a shield bug Elasmostethus interstinctus (L.) (Heteroptera: Acanthosomatidae) over the whole reproductive period. At the beginning and the middle of the reproductive period eggs were smaller than at the end of the period. Clutch mass and number of eggs per clutch decreased in laying sequence, first clutches being much larger than any of the later ones. Lifetime fecundity correlated positively with female size: large females produced more eggs and lived longer than small ones. Egg size did not vary with female size. Offspring survival until adulthood increased with egg weight. …
Immunological and ultrastructural characterization of spirotrichonymphid flagellates from Reticulitermes grassei and R. flavipes (syn. R. santonensis…
2006
AbstractFive species of spirotrichonymphids representing three genera have been studied by light and immunofluorescence microscopy, and by transmission electron microscopy. The genus Spirotrichonympha, represented by S. flagellata from Reticulitermes grassei, is characterized by a compound axostyle composed of several fibers or subaxostyles. The genus Spironympha, represented by S. kofoidi from Reticulitermes flavipes (syn. R. santonensis) and by the two new species S. verticis and S. lanceata, is characterized by flagellar lines restricted to the anterior area and a simple, tubular axostyle. Spironympha verticis and S. lanceata are mainly distinguished by ultrastructural details of their f…
The flagellates of the termite Hodotermopsis sjoestedti with special reference to Hoplonympha, Holomastigotes and Trichomonoides trypanoides n. comb.
2004
Abstract The termite Hodotermopsis sjoestedti harbours a symbiotic fauna of protists comprising at least 11 genera and a much larger number of species. Two oxymonad genera, Pyrsonympha and Dinenympha, are mixed with nine parabasalid genera, two trichomonads, Trichomitopsis termopsidis and Trichomonoides trypanoides n. comb., four spirotrichonymphid genera/species: Spirotrichonympha, Microjoenia, Holomastigotes lanceolata n. sp., Holomastigotes elongatum and three trichonymphid genera/species; Hoplonympha natator, Eucomonympha, Trichonympha. Hoplonympha natator has two anterior symmetrical bundles of ∼60 basal bodies/flagella separated by two parabasal plates. The cell surface is crenelated …
The predatory mirid Dicyphus maroccanus as a new potential biological control agent in tomato crops
2014
The first record of the omnivorous predator Dicyphus maroccanus Wagner (Hemiptera: Miridae) inhabiting tomato crops in the Valencia region (East Coast of Spain) was in 2009. Since then, D. maroccanus has often been found preying on the eggs of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in this area. To evaluate this predator’s potential as a biological control agent, its life-history traits in the presence and absence of prey [(eggs of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae)] on tomato plants were studied under laboratory conditions. Immature stages that preyed on eggs of E. kuehniella developed successfully. However, no nymph completed development on the plant without t…
Protein and amino acid composition of the tergal gland secretions ofBlatta orientalis andEurycotis floridana (Dictyoptera: Blattidae)
1994
Summary Nymphs and adult females ofBlatta orientalis and nymphs ofEurycotis floridana produce a proteinaceous sticky secretion which accumulates on the last abdominal tergites. The proteic patterns do not differ between individuals of the same species. HPLC analyses show that all the common amino acids are found in both species, aspartic and glutamic acids representing 24 to 37% of the total amount of amino acids. InB. orientalis, glutamic acid is the more abundant amino acid whereas inE. floridana it is the aspartic acid. The secretion appears and accumulates rapidly on isolated insects. Behavioural assays revealed that these secretions have a defensive role.
Defensive secretions of nymphs and adults of five species of Pyrrhocoridae (Insecta: Heteroptera)
1993
Abstract The chemical composition of the defensive secretions of the nymphs and the adults of Dysdercus fasciatus was investigated. Thirty compounds were identified from the nymphal posterior dorsoabdominal glands, and 34 from the adult metathoracic glands of both sexes. The data were compared with those reported for other species of Pyrrhocoridae. For the species Dysdercus cingulatus, D. fasciatus , and Pyrrhocoris apertus , 63 identified compounds can be divided into 11 chemical groups: aldehydes, saturated hydrocarbons, acetates, alcohols, terpenes, lactones, ketones, esters, alkenes, acids and miscellaneous compounds. These data and those from the literature on Dysdercus intermedius and…
Growth and population structure of perch in relation to diet in a small humic lake, Valkea-Kotinen
2011
Lake Valkea-Kotinen is a long-term ecological monitoring site in the Evo region of southern Finland .The aim of this study was to investigate the growth and population structure of perch (Perca fluviatilis L.) in relation to diet in Valkea-Kotinen in order to provide reference data for a study investigating effects of increased loading of dissolved organic matter to nearby Lake Alinen Mustajärvi. Valkea-Kotinen was predominantly inhabited by small benthivorous perch. The growth relationship between opercular bone and total length of perch in the lake is similar to those earlier analysed for nearby lakes. Compared to wider growth rates, the growth of perch was slow and similar to those in si…
Éléments du décor du sanctuaire d’Apollon Moritasgus à Alésia : la palestre des thermes et le nymphée
2012
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