THE LARVA AND PUPA OF CARPELIMU8 DEBILI8 CASEY (COLEOPTERA: STAPHYLINI,DAE)*

On a number of occasions Carpelimus debiiis Casey has been found to be numerous at a marine salt marsh at La Salina, near La Misi6n de San Miguel, Baja California Norte, Mexico. This salt marsh was described in some detail by Moore (I964) and its Coleoptera discussed, a key was giv,en 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 mentioned. We are now taking this opportunity to, describe a.nd illustrate the larva and pupa of one of those insects. In July and August, I97, 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 o.f a person with slight sinking. Present with the Carpelimus but in much lesser numbers were Tachys vittiger Le Conte, Thinobius frizzelli Hatch and Ochtkebius 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 substrat.e is placed in a pail of water and the insects removed as they surface (Moore, 954). This method brings adults and some active larvae to the surface but the inactive pupae probably do not surface readily, so. ew were. encountered.

In July and August, I97, 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 o.f a person with slight sinking. Present with the Carpelimus but in much lesser numbers were Tachys vittiger Le Conte, Thinobius frizzelli Hatch and Ochtkebius 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 substrat.e is placed in a pail of water and the insects removed as they surface (Moore, 954). This method brings adults and some active larvae to the surface but the inactive pupae probably do not surface readily, so. ew were. encountered.
Uarpelimus is a large genus of world-wide distribution with several species often found together. Over 352 species were described *Manuscript received by the editor September 10, 197. Psyche December through i969. Because of their small size and generally uniform appearance, members of the genus are difficult to identiy. Larvae. of Staphylinidae are no.torio.usly difficult to associate with adults, except in rare circumstances such as the present one. They are not easy to rear, the larvae often being canabalis.tic when confined in close quarters. Only twice bmore have larvae o,f this genus been made known. Paulian (I94) described and illustrated the larva of the Holarctic species C. bilineat.us Step'hens and Kasule (1968)  with three ocelli in an uneven row o.n each side; epicranial suture about one-half the length of head. Labrum lo.nger than wide, narrowed and truncate in front. Antennal fossae located at sides of head abo.ve bases of mandibles. Antennae t'hree-segmented; first segment about as lo.ng as wide; second segment a little wider than first and about twice as long as wide with the modified aco.rn seta near the apex nearly as large as third segment, born at an obtus.e angle; third segment less than half ,as wide as seco.nd, about as long as wide, with a small modified acorn-like seta at apex. Mandibles arcuate, with t'.hree small .equal teeth arranged in a triangle at apex. Maxil-1.ary palpi three-segmented; first segment about twice as long as wide; second segment a little narrower than first, narrowed from base: to pointed apex. Lacinia triangular, widest at base, spinose or inner edge. Labial palpi two-segmented; first segment lo.nger than wide.; second segment narrower than first, about as. long .as wide. Pronotum, mesonotum and metanotum wider than long, the last two ea.ch wider than preceding. Abdominal terg:ites each wider than metanotum, more than twice as wide as long, fifth tergite widest, pseudopod subcylindrincal, slightly longer than wide, slightly narrowed t:ro.m ba.se to apex. Urogomphus one-segmented, pointed, slightly longer than pseudopod. Many specimens, La Salina, Baja California Norte, Mexico,, Salt Mars'h, August 3, I97, Ian Moore collector.
The only noticeable difference between this larva and Paulian's description of that of G. biliniatus is that in debilis the apex of the mandible is formed of three small teeth arranged in a small triangle whereas in biliniatus Paulian's illustration shows two small subequal 29,I mm 4 Figures 1-4. Cartelimus debilis. Fig. 1, larva; Fig. 2, renter of pupa; teeth, one before the other, with a minute denticle between, and his description states that the apex of the mandible is bidentate. The pupae of Coleoptera are so poorly known that it is ditficult to choose with certainty characters which will be of diagnostic value. However, studies by Jerome Rozen (959,963a,963b) indicate that location of tuberculate setae on va.rious parts of the body, length and shape of elytra, wings and urogomphus are probably most useful; so those characters have been given the most attention in the ollowing description.

Pupa o Carpelimus debilis Casey
Pupa exarate, elongate, pale, not chitinized in any part; various parts of the body with long slender setae, each arising rom a surface so slightly elevated that it can hardly be said to be tuberculate.
Head venterally reflexed so that only a small part is visible rom above; with three ocelli in a row on each side; on .each side with two setae at ront margin, one discal seta and three setae at lateral margin. Pronotum irregularly ovoid, on each side with two setae at ront margin, one at lateral margin and two. at posterior margin. Elytra very little longer than wide, standing at right-angles to body, posterior margin, when viewed from above, with an obtusely angulate projection in the middle, without setae. Wings narrower than and about twice as long as elytra, held away rom the body at an angle of about 45 degrees, without setae. Mesothorax and metathorax without setae. First abdominal segment on each side with one discal and one lateral seta. Abdominal segments two through six on each side with a single lateral seta.