BIOLOGICAL NOTES ON OCYPUS OLENS , 
A PREDATOR OF BROWN GARDEN SNAIL, 
WITH DESCRIPTIONS OF THE LARVA AND PUPA 
(COLEOPTERA: STAPHYLINIDAE) 1 
By R. E. Orth, Ian Moore, T. W. Fisher and E. F. Legner 
Division of Biological Control, Citrus Research and Agricultural 
Experiment Station, University of California, Riverside 92502 
INTRODUCTION 
In a recent article by Orth, Moore, Fisher, and Legner (1975) 
laboratory studies of the snail eating habits of an adult specimen of 
Ocypus olens Muller were reported. Since then there has been op- 
portunity to conduct similar studies of several larvae of the same 
species. The egg remains unknown. These larvae readily consumed 
snails, thus also demonstrating a potential for snail control. This 
view is further encouraged in the Riverside garden of one of the 
authors (I. Moore) which has a well established population of 
O. olens but a very low population of Helix aspersa Muller (brown 
garden snail). Other nearby gardens where O. olens appears not to 
be established have much higher population densities of H. aspersa. 
The host snail employed in our laboratory studies was Helix 
aspersa. In California this snail has long been considered a major 
agricultural and suburban pest with an omnivorous diet which in- 
cludes living and decaying vegetables, flowers, ground cover, citrus 
leaves and fruit as well as paper labels and cardboard cartons and 
cadavers of its own species. 
The rove beetle Ocypus olens , sometimes referred to as the devil’s 
coach horse, is a large (to 32 mm) black staphylinid indigenous to 
Europe. In North America it is known only from California where 
it was first recorded in southern California in 1931 (Orth, et al., 
1975). Since that time distributional records extend about six hun- 
dred miles to the north. 
In California both Ocypus olens and Helix aspersa seem to prefer 
cultivated or landscaped habitats. In the field we have seen and 
collected O. olens only in areas disturbed by man. This beetle there- 
fore would seem to pose no threat to California’s native land snails, 
which are generally found in the undisturbed hillsides, mountains, 
and deserts. 
1 Manuscript received, by the editor September 5, 1975. 
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