1977] 
Robinson & Valerio — Salticid Spiders 
3 
Figure 1. Adult female Phiale sp. feeding on anisopteran dragonfly, Navy Pipe- 
line Road, Canal Zone, Panama. June 18th 1976. 
of individuals to the exact place where a member of their colony 
is in danger. The response to the alarm pheromone is very rapid 
and may occur within seconds (Janzen 1966). This adaptation 
could effectively deter salticid predation on the ants were it not 
for the use of the dragline described above. An unidentified salti- 
cid (not collected) was observed making effective use of this tech- 
nique at a lowland site in Guanacaste, Costa Rica. The Pseudo- 
myrmex were attacked in an Acacia tree. The spider simply pounced 
on the ant, dropped off the branch and held the ant, suspended 
on the end of the dragline, and ate it. The ants, attracted by the 
