THE LARVA AND PUPA OF 
CARPELIMUS DEBILIS CASEY 
(COLEOPTERA: STAPHYLINIDAE)* 
By Ian Moore and E. F. Legner 
Division of Biological Control, Department of Entomology 
University of California 
Riverside, California 92502 
On a number of occasions Carpelimus debilis Casey has been 
found to be numerous at a marine salt marsh at La Salina, near 
La Mision de San Miguel, Baja California Norte, Mexico. This 
salt marsh was described in some detail by Moore (1964) and its 
Coleoptera discussed, a key was given by Moore for the separation 
of larvae of some of the Staphylinidae found there but no detailed 
descriptions or illustrations were presented, nor were pupae men- 
tioned. We are now taking this opportunity to describe and illustrate 
the larva and pupa of one of those insects. 
In July and August, 1971, a very large colony of C. debilis was 
found in an area about two meters square in Moore’s Zone One. 
The substrate was a mixture of sand and mud of a consistency 
which would support the weight of a person with slight sinking. 
Present with the Carpelimus but in much lesser numbers were Tachys 
vittiger Le Conte, Thinobius frizzelli Hatch and Ochthebius sp. and 
large numbers of larvae, almost entirely Carpelimus. Thousands of 
adult C. debilis , hundreds of larvae and three pupae were collected. 
The pupae were staphylinid pupae of about the size of Carpelimus so 
it seems very likely that we have properly assigned them. A few 
meters away in Zone One was another small area of similar material 
but too wet to support the weight of a person. That area contained 
large numbers of the same species of Ochthebius but few, if any, 
other insects. Insects were collected in these areas by the water 
flotation method in which a shovel of substrate is placed in a pail of 
water and the insects removed as they surface (Moore, 1954). This 
method brings adults and some active larvae to the surface but the 
inactive pupae probably do not surface readily, so few were en- 
countered. 
Carpelimus is a large genus of wo rid- wide distribution with sev- 
eral species often found together. Over 352 species were described 
* Manuscript received by the editor September 10, 1973 
289 
