THE LARVA OF PLATYSTETHUS SPICULUS ERICHSON 
(COLEOPTERA : STAPH YLINI DAE) 
AND ITS OCCURRENCE IN BOVINE FECES 
IN IRRIGATED PASTURES* 
By E. F. Legner and Ian Moore 
Department of Entomology, University of California, 
Riverside, California 92521 
Platystethus is a relatively small genus (35 described species) 
with only two species being known to be indigenous to the United 
States. The Nearctic species were reviewed by Moore and Legner 
(1971). The larva of one of these, P. americanus Erichson, was 
described and illustrated by Paulian (1941). The larvae of the other 
species, P. spiculus Erichson, is described here. It goes to Platy- 
stethus in Paulian’s (1941) key to the genera of the larvae of the 
Staphylinoidea. Several larvae were taken by Berlese extraction as 
previously described (Legner et al., 1975) in company with many 
adults of P. spiculus in bovine manure that, at the time, contained 
no other staphylinids. Ten to 25 1 L samples were taken at random 
from bovine feces deposited in green and dry irrigated pastures at 
3 sites near Calexico, California between 9 AM and 11 AM over 
several sample dates from October 22, 1974 to April 22, 1975. Two 
age groups of manure were distinguished: 12 hr and 24-48 hr old. 
KEY TO THE LARVAE OF THE SPECIES OF PLATYSTETHUS 
INDIGENOUS TO THE UNITED STATES 
1 . Acorn-like seta at apex of second antennal segment equal in size 
to third antennal segment spiculus Erichson 
Acorn-like seta at apex of second antennal segment only half as 
long as third antennal segment americanus Erichson 
Larva of Platystethus spiculus Erichson 
Length 3.8 mm. Body elongate, pale, integuments mostly trans- 
parent with the head and mouthparts tinged with brown, the man- 
* Manuscript received by the editor June 10, 1977. 
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