TEMPERATURE-INDUCED CHANGES IN THE CALLS 
OF THE GREEN LACEWING, 
CHRYSOPERLA PLORABUNDA (NEUROPTERA: 
CHRYSOPIDAE)* 
By Charles S. Henry 
The Biological Sciences Group 
Box U-43, University of Connecticut 
Storrs, Connecticut 06268 
Animals communicate acoustically in many different ways and 
for many different purposes; in fact, a vast literature exists on the 
subject, and comprehensive efforts to summarize current knowledge 
have not been attempted since the early 1960’s (e.g., Lanyon and 
Tavolga 1960, Busnel 1963). Insects are especially rich in singing or 
noise-making species, and it seems likely that every insect order will 
eventually prove to include acoustically active taxa. Neuroptera has 
long been regarded as a “silent” order of primitive, behaviorally 
simple insects. However, recent work suggests that many, if not 
most, species of the large neuropteran family Chrysopidae are 
characterized by complex courtship displays accompanied by a 
specialized form of acoustical signalling (Smith 1922, Toschi 1965, 
Ickert 1968, Henry 1979 and 1983b). Such lacewing calls or songs 
are not acoustical in the traditional sense, but instead consist of 
species-specific substrate-borne vibrations produced by vigorous, 
stereotyped jerking motions of the insects’ abdomens: a phenome- 
non known as tremulation in other insects (Morris 1980; Henry 
1980a, c), and found also in the ancestral neuropteroid taxon 
Megaloptera (Rupprecht 1975). Calling behavior is most elaborate in 
Chrysoperla Steinmann; conspecific males and females of species 
within that genus cannot mate without first reciprocally exchanging 
similar or identical vibrational signals in a prolonged courtship duet 
(Henry 1980b, 1983b). The best studied species in this regard is 
Chrysoperla plorabunda (Fitch), a common North American form 
that for some years was considered synonymous with the morpho- 
logically identical Eurasian species Ch. cornea (Stephens) (Tjeder 
1960, Henry 1983a). Both sexes of this species, when sexually 
* Manuscript received hy the editor August 2. 1983. 
343 
