348 
Psyche 
[December 
Peru, I found a similar association between a Curimagua and a 
Diplura in the “white sand forest” of Mishana. 
Diplura sp. is a beautifully colored spider that measures up to 4 
cm in length and builds sheet- or funnelwebs spreading up to 50 X 50 
cm. The spider rests in the entrance of its retreat, a silken tube, 
waiting for prey to fall onto or crawl over the sheet. The prey is 
bitten in a sudden lunge and dragged into the retreat for consump- 
tion. In a few minutes the prey (e.g., a cricket) will be a mushy and 
liquified body, due to the combined action of the masticating 
movements of the relatively large chelicerae and the regurgitated 
digestive enzymes of the spider. Diplura s prey, as judged from the 
remains, seems to consist mainly of beetles (Coleoptera), crickets 
(Gryllidae), and ants (Hymenoptera). Millipedes (Diplopoda) and 
tailless whipscorpions (Amblypygi) were also found, as was a partly 
digested dendrobatid frog (Anura, Dendrobatas auratus). 
In contrast to the diplurid host, Curimagua bayano is a tiny, 
mitelike spider. The pale body of the adult female is globular and 
measures not more than 1 .3 mm in length. The male is equally small; 
for exact measurements, see Forester and Platnick (1977). Curi- 
magua bayano was found in the retreats of several webs of Diplura. 
The highest number per host was three females and one male, all in 
the relatively small web (30 X 30 cm) of a male Diplura. An egg case 
which was also found in the host’s retreat, and which was assumed 
to be of curimaguan origin, consisted of four small eggs incorpo- 
rated into a transparent and fluffy sphere (diameter 0.8 mm) of 
loosely spun silk. Curimagua crawls about between the silken 
threads of the host retreat, several centimeters behind the entrance, 
near the place where the host feeds. Because of its minute size, 
Curimagua has no difficulty in negotiating the fine mesh of silk. 
Often the animals were observed riding on the diplurid, perched on 
the center of its cephalothorax, apparently clinging to the fine hairs 
that cover it. Even their host’s violent lunge for prey does not shake 
them off. I never saw the host react to Curimagua crawling about in 
the web or traversing the body of the host, even when it moved 
across the host’s eyes (Figure 1). Diplura collected on Pipeline Road 
(where Curimauga was absent in ten Diplura webs inspected) also 
showed no hostile reaction when Curimagua climbed “aboard,” 
suggesting that instead of being ignored the associate may not be 
perceived by its host. 
