502 
Psyche 
[Vol. 92 
of Texas at Austin; B. craniifer — Harvard University culture 
originally from L. M. Roth; collection by D. Simon in Yucatan, 
Mexico in 1968; A. tessellata — collection by R. H. Barth and F. A. 
McKittrick in Panama in 1962; B. fumigata — Harvard University 
culture originally from L. M. Roth. R. H. B. and F. A. McK. thank 
STRI for the use of their facilities in Panama. 
Summary 
This paper presents an account of a previously unreported form 
of pseudofemale behavior in cockroaches and comments on its pos- 
sible adaptive significance. Females in most species of cockroaches 
must play an active role in order for copulation to occur. A recep- 
tive female “mounts and feeds” upon the exposed dorsal abdominal 
surface of a male performing the “full wing raising display”. This 
serves to position the female so that the male may achieve genital 
connection. The appearance in males of the female pattern of 
mounting and feeding is known as “pseudofemale” behavior. 
Remarkably intense male-male aggression in courtship situations is 
found in the neotropical genera Blaberus, Archimandrita, and Byr- 
sotria of the Tribe Blaberini (Blattaria, Blaberidae, Blaberinae). 
This can be explained as the result of sexual selection. Courting 
males frequently disrupt the courtship of rival males. Males may 
attack at any stage of the courtship of their rivals. In this context, 
pseudofemale behavior appears to function as part of an array of 
aggressive tactics males may employ to prevent the scarce receptive 
females from copulating with their rivals and thus increase their 
own prospects for achieving copulation. In these genera, pseudofe- 
male behavior operates as follows. First, a male mounting a display- 
ing rival effectively monopolizes that male’s abdomen and precludes 
the receptive female from mounting. Second, after the pseudofemale 
mounting and feeding sequence has placed the displaying male in a 
highly vulnerable position, the pseudofemale performer, unlike a 
receptive female, attacks the displaying male by biting his wings 
and/or the region of the first abdominal tergite. This causes the 
displaying male to flee. 
References Cited 
Barth, R. H., Jr. 1964. The mating behavior of Byrsotria fumigata (Guerin) 
(Blattidae, Blaberinae). Behaviour 23: 1-30. 
