MYRMECOPHILIC RELATIONSHIP OF PELLA 
(COLEOPTERA: STAPHYLINIDAE) TO 
LASIUS FULIGINOS US (HYMENOPTERA: FORMICIDAE) 
By B. Holldolber*, M. Moglich**, U. Maschwitz*** 
Introduction 
A large number of staphylinid beetles are closely associated with 
ants and termites (for review see Wilson 1971, Kistner 1979). Those 
species living with ants are commonly called myremcophiles. At 
least a few ( Atemeles , Lomechusa ) have “broken” the communica- 
tion code of their host species and are thereby able to become 
completely integrated in the social system of the ants (Holldobler 
1967, 1970, 1971). In an attempt to understand the evolutionary 
pathways of this highly specialized social parasitic behavior, we 
studied closely related staphylinid species that do not live within the 
ant society but instead occupy the foraging trails and garbage 
dumps of an ant nest. 
Many of such myrmecophilous staphylinids can be found with the 
formicine ant Lasius fuliginosus and most of them belong to the 
genus Pella. Apparently these beetles are not endowed with the 
behavioral repertory that would enable them to live within the ant 
colony, although they seem to have a close ecological association 
with ants (Holldobler 1972). 
Kistner (1971) redefined the genus Zyras and raised the former 
subgenus Pella to generic rank. The first behavioral observations 
concerning Pella ( =Zyras , Myrmedonia ) were published by Was- 
mann (1886, 1930). He stated that these beetles feed on dead or 
disabled ants, but that they also lie in wait near the entrance and 
hunt ants returning to the nest. Furthermore, Wasmann pointed out 
that because of their generalized and primitive structure these 
beetles can be regarded as close to the ancestral forms from which 
some of the more specialized staphylinid myrmecophiles were 
derived. 
♦Department of Biology, Harvard University, Cambridge, Mass., USA. 
♦♦Present address: Am Lowentor 15, Darmstadt, W. -Germany. 
♦♦♦Fachbereich Biologie (Zoologie) der Universitat Frankfurt, W. -Germany. 
Manuscript received by the editor October 19, 1981. 
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