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Psyche 
[Vol. 95 
not be excessively skewed by a tendency to lay male eggs on small 
hosts and female eggs on large hosts. Host size appears to be asso- 
ciated with sex of parasitoids in a number of families of wasps 
(Clausen 1939, Charnov 1982, Deyrup and Manley 1986). 
Seasonal Occurrence 
Specimens of A. azureus have been collected at the Archbold 
Biological Station from May to November, and Evans (1951) listed 
collections in the southeastern U.S. from April to December. There 
are probably several generations of wasps per year. The host spider 
may live several years, and all sizes of hosts are available through 
the year. There is no reason to suppose A. azureus shows any sea- 
sonality other than protracted or arrested development during cool 
weather. 
Discussion 
Alio chares azureus differs structurally, ecologically, and behav- 
iorally from all other pompilids that have been studied. The struc- 
tural pecularities of the adult suggest two other genera of 
non-fossorial pompilids, the Old World Homonotus and the New 
World Notocyphus. Members of these genera paralyze and oviposit 
on free-living spiders, which recover from the effects of the sting and 
resume their normal activities. After the larva has fed for about a 
week, the spider dies (Williams 1928, Richards and Hamm 1942, 
Iwata 1942). The genus Minagenia may have similar habits, but has 
not been studied except for casual rearings (Kaston 1959). Numer- 
ous pompilids, including species of the tribe Aporini and some spe- 
cies of Pepsis, use the burrows of spiders as ready-made nests for the 
larvae (Evans 1953). A. azureus is apparently unique among pompil- 
ids in its use of the web for deposition of the spider and in having a 
larva that feeds and constructs its cocoon in the web. This is not to 
say that A. azureus occupies a previously unexploited adaptive 
zone, as members of the entire ichneumonid tribe Polysphinctini are 
very similar to A. azureus in larval habits (Townes and Townes 
1960). 
In its ecology A. azureus may resemble polysphinctine ichneu- 
monids more than it does any pompilid, but A. azureus is not a 
particularly primitive species, nor even a specialized representative 
of a primitive offshoot of the Pompilidae. Evans (1953) points out 
