1979] 
Eberhard — Argyrodes attenuatus 
409 
The spiders replaced the threads they walked along as they 
moved, and thus probably held one broken end with a leg and 
spanned the gap with the body as they rested on the web, but they 
did not tense the lines or sag them suddenly when disturbed as do 
other spiders with similar reduced webs such as Miagrammopes 
(Akerman 1932, Lubin et al. 1978) and Ulesanis (Marples 1955). 
Attack Behavior and Prey 
Twenty seven spiders were found feeding on or resting near 
enswathed prey (Table 1). In addition I saw mature females move 
after but fail to capture a mature male theridiid spider and a small 
unidentified spiderling on lines in their webs. Some of the spiders’ 
prey were judged to be substantially heavier than the A. attenuatus 
which captured them. In general, small A. attenuatus fed on small 
flies, and larger ones fed mostly on immature non web-building 
spiders. The ways these prey were secured was determined by direct 
observation and experiment. 
When small spiderlings of several species were placed on webs of 
mature female A. attenuatus, the owners consistently responded by 
moving toward them and attempting to attack. In a typical capture 
sequence a spiderling was held dangling from its trail line, and 
Fig. 1. Web of a mature female Argyrodes attenuatus. None of the lines were 
sticky. (Drawn from a photograph; scale line =10 cm). 
