240 
Psyche 
[June-September 
Later we became interested in the developmental biology of 
sexual size dimorphism and intrasexual size poymorphism (Robin- 
son & Robinson, 1976b, Robinson, B. & M. H. Robinson, 1978). 
However, orb-weaving spiders are not easy subjects for this type of 
study, and we turned our attention to mantids, in particular to the 
dead leaf mantid, Acanthops falcata. A. falcata proved to be an 
ideal subject and could become a most useful laboratory'animal. It 
is an extremely efficient predator, attacking, at all instars, any live 
prey from drosophiloid flies up to insects of almost its own size. In 
captivity it becomes very ‘tame’ and will wait for food to drop when 
the cage lid is raised, and will often take food directly from the 
forceps. Although the species has to be raised in separate cages, the 
containers we used were small, inexpensive, readily available and 
easily manageable. 
We think that A. falcata has great potentialities as an experi- 
mental animal. It has an extensive behavioral repertory, with an 
efficient predatory strike and a complex startle display (first de- 
scribed by Crane, 1952). We have demonstrated (Robinson & 
Robinson, in prep.) that receptive females secrete an attractant to 
which males fly. The pheromone remains to be isolated. The female 
has a relatively large head capsule and brain and the large eyes have 
excellent movement detection and depth perception. It should be an 
excellent subject for neurophysiological studies. Our success rate of 
rearing nearly 1,000 individuals over several generations has been 
about 95%, and out methods should prove of interest to ethologists, 
neurophysiologists, biochemists and developmental biologists wish- 
ing to work with this mantid. 
Culture Methods 
THE INSECT. 
Acanthops falcata is a small neotropical mantid of the family 
Hymenopodidae. For a mantid it has an unusual degree of sexual 
dimorphism. The flightless female (Figure 1) resembles a curled 
dead leaf and weighs 400-500mg. The male, which flies well, 
resembles a flat dead leaf, and weighs under 200mg. 
A brief summary of the life history is given here. Details of instar 
duration, sizes and weights at each instar, variability of number of 
instars and mating behavior are to be published separately (Robin- 
son & Robinson, in prep.). 
