1982] 
Darling — New Species of Krombeinius 
311 
median areas with weak transverse rugae or aciculate; basitarsomere 
not conspicuously lengthened. Forewing with marginal vein longer 
than postmarginal, postmarginal vein long, about 3 times length of 
stigmal vein, stigmal vein making either a right or oblique angle 
with marginal vein. 
Metasoma: petiole short, transverse, the tergum forming a ridge 
along anterior face of gaster, sternum shifted posteriorly; gaster 
triquetrous, T2 and T3 fused, covering most of dorsum; T2 without 
distinct basal fovea; T3 much longer than T2, subquadrate, slightly 
wider than length along midline; ovipositor ventral, not upturned, 
sheaths not distinctly exserted; male genitalia with distinct para- 
meres [n = 1, K. eumenidarum, Fig. 2], 
Discussion: 
The male genitalia of Krombeinius eumenidarum (Fig. 2) are 
similar to those of species of Perilampus : the parameres are distinct, 
and strong setae are distributed on these lobes. This configuration 
occurs throughout the Chalcidoidea (see Domenichini 1953) and is 
regarded as plesiomorphic. In Euperilampus a derived condition is 
found (Darling 1983): distinct parameres are lacking, and the basi- 
paramere has a patch of strong setae distributed on transparent 
areas laterad of the ventral lobe (Fig. 4). 
The labrum of Krombeinius eumenidarum (Fig. 3) has a narrow 
central stalk, not found in other perilampid genera (Riek 1966; 
Domenichini 1969; Darling, unpublished). However, the labrum 
does share synapomorphies with species of Euperilampus (Fig. 5) 
including a reduced number of digits (7 or 8), a pair of smaller, 
sessile setae not associated with digits, and a strong median exci- 
sion. The narrow stalk distinguishes the labrum of Krombeinius 
from those of Euperilampus, and is postulated as an autapomorphy 
of Krombeinius. All other perilampid labra are 1 0— 1 2-digitate, and 
not as strongly excised medially. 
The host association of the type species of Krombeinius [larva of 
Vespidae: Eumeninae] is different from that of any other described 
perilampid, although solitary Sphecidae are attacked by some Peri- 
lampus species (e.g., Perilampus nitidus, primary parasitoid of 
Ectemnius paucimaculatus. ltrombein 1964, as P. canadensis). This 
behavioral character is regarded as an additional autapomorphy for 
the genus Krombeinius. 
