The lesser wax moth, Achroia grisella (Fabricius) (Pyralidae: Galleriinae), uses an altrasonic communication system for mate calling The male produces a 100 kHz sound by striking its tegula with the forewing. This calling sound induces virgin females to orient toward males. Although the pheromone released from the male's wing glands may stimulate kinesis in females, it does not elicit orientation. Female moths are attracted toward synthetic 40 and 72 kHz sounds which simulate the pulse length and repetition rate of the male's calling signal.

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Several biophysical properties of members of Aleyrodidae and Aphididae were examined in order to explore how homopterous insects fly. Five species of aphids were found to weigh significantly more than five whitefly species (range 1.14-7.02xl0−4g for aphids vs 3.3-8.0x 10−5g for whiteflies) and to have significantly larger wing surface areas (range 0.0103-0.1106 cm2vs 0–0096-0.0264cm2). As a consequence whiteflies and aphids can be partitioned into two groups with respect to wing loading (range 0.00633-0.01412 gcm−2 for aphids, 1.74-5.23x 10−3gcm−2 for whiteflies). Members of the two families are also separated in terms of wingbeat frequency (range 81.l-123.4Hz for aphids, 165.6-224.2 Hz for whiteflies). Since our animals were much smaller than any insects examined previously for these parameters, values were compared with the same parameters for 149 insect species recorded in the literature. Using these data, we found wingbeat frequency to be significantly correlated with wing loading only in insects weighing more than 0.03 g. Larger insects seem to employ a strategy similar to other flying animals, by compensating for high wing loading with higher wingbeat frequencies. The lack of correlation for these two parameters in insects weighing less than 0.03 g probably results from the use of different flying strategies. These include employment of a clap and fling mechanism and the possession by some of exceedingly low wing loading. Also, small insects may have reduced settling velocities because they possess high drag coefficients. Previous studies which failed to establish a relationship between wing loading and wingbeat frequency in larger insects may have considered too few subjects or too great a range of body masses. The mass range is important because smaller insects which employ increased wingbeat frequency must use rates exponentially higher than those of larger insects utilizing the same strategy.

ABSTRACT. Tympanic hearing organs (ears) are reported for several tiger beetle (Cicindelidae) species. The paired ears are positioned bilaterally on the first abdominal tergum and consist of cavities covered by thin tympana. When the beetle is not flying the elytra covers its ears and reduces their sensitivity to sound. However, when the beetle is flying, its exposed ears are capable of detecting ultrasonic pulses. Under a microscope, beetles with their elytra artificially raised contract their abdomens in response to ultrasound. Ultrasonic emissions directed toward flying beetles induce them immediately to fly downward and land, a response which probably aids escape from predators, particularly echolocating bats. Other possible uses for the ears are the avoidance of diurnal insect predators and intraspecific communication.