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Free-flying honeybees exhibit remarkable cognitive capacities but the neural underpinnings of these capacities cannot be studied in flying insects. Conversely, immobilized bees are accessible to neurobiological investigation but display poor visual learning. To overcome this limitation, we aimed at establishing a controlled visual environment in which tethered bees walking on a spherical treadmill learn to discriminate visual stimuli video projected in front of them. Freely flying bees trained to walk into a miniature Y-maze displaying these stimuli in a dark environment learned the visual discrimination efficiently when one of them (CS+) was paired with sucrose and the other with quinine solution (CS−). Adapting this discrimination to the treadmill paradigm with a tethered, walking bee was successful as bees exhibited robust discrimination and preferred the CS+ to the CS− after training. As learning was better in the maze, movement freedom, active vision and behavioral context might be important for visual learning. The nature of the punishment associated with the CS− also affects learning as quinine and distilled water enhanced the proportion of learners. Thus, visual learning is amenable to a controlled environment in which tethered bees learn visual stimuli, a result that is important for future neurobiological studies in virtual reality.

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The response to intra-and interspecific assembling signals was tested in three species of Chagas' disease vectors. As previously described for Triatoma infestans, larvae of both species, T. sordida and T. guasayana, aggregated on papers impregnated with their own excrement. Moreover, bugs belonging to each of the three species also aggregated on papers contaminated with faeces from the other two, with the only exception of the larvae of T. guasayana, which did not assemble on faeces of T. sordida. In all cases, the response to interspecific excrement was as strong as that to the intraspecific one. The nonspecificity of the signal is discussed in the context of the ecological association of the three species and their role as vectors of Chagas' disease.

The gorging response of 3rd‐instar nymphs of the vector of Chagas' disease Triatoma infestans Klug to different diets was analysed using an artificial feeder which allows one to feed a great number of bugs simultaneously. Citrated blood was more acceptable than heparinated blood, either stored at 4°C or at –20°C. Freezing of blood at –20°C and their subsequent haemolysis did not affect the intake of citrated blood when it was defrosted immediately before the experiment, but in fact when this occurred 36 hs before. The addition of mice odours to the artificial feeder did not improve the reaction of the bugs to the food it offer. Saline solutions without phagostimulants proved to evoke gorging. Zusammenfassung Die Zucht von Triatoma infestans King (Het., Reduviidae) ohne lebendes Wirtstier. I. Einflüsse auf die aufgenommene Futtermenge Es wurde die Blutaufnahme von Nymphen im 3. Stadium von Triatoma infestans, dem Überträger der Chagas‐Krankheit, untersucht. Geboten wurden verschiedene Diäten in einer künstlichen Futterquelle, die die gleichzeitige Fütterung einer großen Anzahl von Wanzen ermöglichte. Bei 4°C als auch bei –20 °C konserviertes Citratblut wurde besser akzeptiert als Heparinblut. Die Konservierung des Blutes bei –20°C (d. h. Hämolysis) hat die Akzeptanz des Blutes dann nicht beeinflußt, wenn es kurz vor der Fütterung aufgetaut wurde. Lag der Auftauzeitpunkt länger zurück (36 h) wurde von den Tieren weniger Blut aufgenommen. Der Zusatz von Duft von Mäusen an der Futterquelle verbesserte die Aufnahme nicht. Die Tiere nahmen auch reine Salzlösungen ohne Phagostimulantien auf.

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