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Irradiation experiments in freshly killed black papilionids under natural sunlight and minimized wind convection showed that antennae, wings and thorax heat with different warming rates and reach different specific excess temperatures under moderate radiation. While the “low-mass” antennal clubs retain almost temperature of the ambient air, the well-insulated “medium-mass” basal wing veins attain vulnerable excess temperatures after about 15 s when fully exposed, T equilibr of antennae is 28°C and of forewing 46°C both after 30 s, T equilibr of the thorax is 42°C after 8 min, all at T ambient of 26°C and under 54 mW/cm 2 . The antennal clubs are optimally suitable for measurement of ambient temperature in spite of being fully exposed to the sun. They are equipped with sensilla basiconica. These poreless sensilla with triads of Type I receptors (typical for thermo/hygroreceptors) and their ultrastructure are described for the first time in butterflies. By scanning the wing veins of free-resting Troides with a calibrated light beam of 1 mm in diameter, a slow wing closing reaction could be evoked at discrete sites along most veins, indicating the existence of a sensory system for increasing temperatures. A heating rate of 2.4–4°C/s of the irradiated wing area was necessary to elicit a response. The applied radiation produced an equilibrium temperature of 39 ± 3°C at the basal veins A2 and A3 after about 12 s. With axonal filling (CoCl 2 ) and electron microscopic techniques multiterminal sensory cells (Type II receptors) are traced and described. Some of them are suggested to function as warm receptors. The different role of the peripheral thermoreceptor systems in thermoregulation is discussed.

Duftstoffe aus den abdominalen Haarbüscheln des männlichen Totenkopfschwarmers Acherontia atropos L. (Lepidoptera: Sphingidae) Pherom ones 92 [1], Odorous Substances from the Abdom inal Hair Brushes of the Male Sphingid Moth Acherontia atropos L. (L epidoptera: Sphingidae) Hans Jürgen Bestm ann, Joachim Erler, Otto Vostrowsky From abdominal hair brushes of male hawk moths Acherontia atropos (Lepidoptera: Sphingidae) 24 volatiles have been detected and identified by GC-MS analysis, caryophyllene (17), humulene (18), linalool (6), linalyl propionate (12) and geranic acid methylester (9) comprising the main constituents. Analyzing the terpenoid composition of volatiles from insects reared on different host plants as well as that of the essential oils from these plants it could be demon­ strated, that most components of the odour blend are not derived from the food plants but can be de novo synthesized by the insects.

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