332 
Psyche 
[Vol. 89 
The data differ from those of Muma and Jeffers regarding prey 
selection by Chalybion and Sceliphron. In their study in Maryland, 
the theridiid Latrodectus mactans constituted 25% of all prey taken 
by Chalybion. Locally, L. mactans is provisioned less frequently, 
comprising less than 5% of all prey taken. These differences may be 
due in part to the availability of more prey species in Florida. 
Spiders not found in Maryland nests but taken by Chalybion and 
Sceliphron in Florida include Tetragnatha guatemalensis O. P.- 
Cambridge, Tetragnatha pallescens F. P. -Cambridge, Pisaurina 
undulata, Mecynogea lemnis cat a (W alckenaer), G aster acantha can- 
criformis (Linnaeus), and Tidarren sisyphoides. M. lemniscata and 
G. cancriformis were also found provisioned in Sceliphron cells. 
Maryland constitutes the northern most distribution for M. lemnis- 
cata (Kaston, 1978). G. cancriformis ranges only as far north as 
North Carolina (Levi, 1978). The distribution of T. sisyphoides in 
North America is restricted to the southern United States and Mex- 
ico (Levi, 1955). 
Nest Sites as Spider Habitat. Mud-dauber nest sites may be par- 
ticularly good habitats for some spiders. Benefits to spiders at such 
sites include the following: 
1. Mud nests afford environmentally buffered refugia and brood 
chambers and may provide cryptic backgrounds. 
2. Additional prey is available, including the wasps themselves, 
other spiders (Tolbert, 1975), mites and hymenopterous and 
dipterous parasites of mud-daubers, “renting” Arthropods 
that use empty mud-dauber cells (Dermaptera, lepidopterous 
larvae and non-sphecid wasps) and nest associates such as 
Psocoptera. 
3. The risk of predation from wasps nesting at these sites is 
reduced. 
Although somewhat counter-intuitive, the probability of wasp 
predation appears to be lower for spiders living at sites where wasps 
nest. The greatest threat may exist for smaller, naive individuals, 
and a small cost is probably incurred by those spiders whose web is 
damaged after intercepting a wasp. However, the benefits of living 
amidst mud-daubers may outweigh these potential costs. Associa- 
tions of predator and prey at predator nests sites are not without 
precedent. Nesting of passerines with raptors has been reported 
