We conducted a study to explore which beetles utilize dead twigs in a Louisiana secondary forest and the effect of debris position on the beetle community. Twigs averaging 14 mm in diameter from one tree of Quercus falcata Michaux (southern red oak) were placed randomly into bundles of ten. At each of three sites, three bundles were laid on the ground, three were propped at the base of a living tree, and three were tied tightly above the ground against the branch of a living woody plant. The bundles were collected 10 months later and each was placed into an emergence chamber. More than 400 adult Coleoptera specimens were collected, representing 35 species within 16 families. Cerambycidae (longhorn beetles) and Curculionidae (weevils) exhibited the highest species richness, with nine and five species, respectively. Species richness was significantly different among treatments. Bundles placed on the ground had the lowest richness, aboveground bundles had the highest, and propped bundles were intermediate. Twelve species (34%) were represented by singletons.

Nanos viettei (Paulian, 1976) is a nocturnal generalist dung beetle mostly feeding on carrion. Despite its relatively small size (6 mm), N. viettei is a long–lived (up to two years) species with extremely low life–time fecundity (maximum four offspring) and very low mobility (based on mark–recapture studies). Matings are promiscuous and, exceptionally for Canthonini, males typically guard the female for at least several hours after mating. There is no bisexual cooperation or mate courtship unlike in many other Scarabaeidae. Heterospecific copulation was observed in captivity, supporting the hypothesis of genetic introgression between closely related species for which there is some molecular evidence. Hybridization and low hybrid fitness may at least partly explain the exclusive geographical ranges of species in the ‘viettei species-group’.

All available information, both published and unpublished, on the nesting behavior of Trichillum Harold and other Scatimina with fused abdominal sternites, including laboratory breeding results for Trichillum, is presented. These genera exhibit none of the behavioral traits that are characteristic of the Scarabaeinae. In fact, their resource utilization is the simplest known to date for this subfamily, and is similar to that of the majority of the Aphodiini (Scarabaeidae: Aphodiinae). We discuss whether these genera exhibit an ancestral nesting behavior, or have lost nesting behavior. The phylogenetic relationships of these taxa should be the clue to understanding if the behavior analyzed here is a primitive or a derived one, and all evidence points to a loss of the original nesting behavior.

Larval competition and allometry in the stag beetle Dorcus rectus (Motschulsky) were investigated in the laboratory and the field. Allometry indicated three larval groups of different head capsule widths and body masses, representing three instars. A laboratory experiment, in which two larvae were placed on milled decaying wood in test tubes for two weeks, showed that cannibalism occurred in the first and second instars. Cannibals tended to have larger head capsules than their victims. Cannibalizing larvae gained more body mass than non-cannibals. The carbon/nitrogen ratio of decaying wood was much higher than that of larvae, explaining an increased body mass following cannibalism. Sixty-two percent of surviving second instars was wounded by their opponents. When cannibalism did not occur by second instars, large-headed larvae grew but the growth of small-headed larvae was restricted, suggesting strong interference. However, a field study suggested low rates of interference competition between larvae.

Several woodboring insects thrive in coffee plantations due to a surplus of host material as a result of pruning shade trees. The longhorn beetle Tetrasarus plato Bates (Coleoptera: Cerambycidae) disperses and mates at the time this branch pruning is taking place. We describe some general facts of its life cycle and the sexual behavior under field and laboratory conditions.

On Barro Colorado Island, Panama, a series of field observations were conducted to evaluate the role of burrower species of Scarabaeinae (Coleoptera: Scarabaeidae: Scarabaeinae) in the removal of dung. Using tapir dung placed on the soil surface, three species were observed during the diurnal period, five other species were observed in the nocturnal period. Of those eight species, Onthophagus acuminatus Harold was demonstrated to be the most varied behaviorally in obtaining dung, to include kleptoparasitism.

Cyclocephala casanova Ratcliffe and Cave, new species, and Cyclocephala monzoni Ratcliffe and Cave, new species, from Guatemala are described, illustrated, and compared with other species similar in appearance.

Two species in the weevil subfamily Conoderinae are described from Cocos Island, Costa Rica. The more common Hoplocopturus sherrywernerorum, new species, is sexually dimorphic and has a Lechriops-like pattern of setae similar to the Central American H. ochreicollis Champion, although it does not seem closely related to any mainland species. Copturomimus hoguei, new species, is a larger species with elytral costae similar to the widespread Central American C. octocostatus Champion.

For the conservation of the diving beetle Dytiscus sharpi (Wehncke) (Coleoptera: Dytiscidae), which is included on the Red Data List of Japan, it is critical to understand its ecological background. In the present study, we focused on its feeding behavior and nutritional needs under laboratory breeding conditions. First, we made a list of the possible candidates of prey in the same habitats where we caught D. sharpi. We found that the tadpoles of Rana ornativentris (Werner) were the major species present from March to April, when the beetle larvae appeared. Second, under our laboratory conditions, we investigated the size preference of beetle larvae preying on R. ornativentris tadpoles. We found a significant positive correlation between the developing stage of the larvae and the preferred prey size, i.e., the first and third instars preferred smaller and larger prey, respectively, but second instars did not show any size preference. The size of full–grown adult beetles was almost the same as that of wild insects found in the field, indicating that R. ornativentris tadpoles provide almost complete nutrition for larval growth. Finally, we investigated how the size and number of R. ornativentris tadpoles were correlated with the developing stage of beetle larvae. We suggest that it is crucial for Dytiscus larvae to have access to tadpoles of the proper size and amounts, depending on their growth stage.

A new species of Ernobius is described from material collected at the Griffith State Nursery in Wood County, Wisconsin, U.S.A. Ernobius youngi new species is described from a single adult female bringing the number of Ernobius species known from North America north of Mexico to 31.

Ampullae appear to be common in the larvae of some chrysomelid subfamilies. We describe and discuss the occurrence and use of these structures in larvae of Labidomera clivicollis (Kirby), on its host plant Asclepias verticillata L. (Asclepiadaceae) under field and lab conditions. Through film footage, we reveal that ventral ampullae are apparent on all ten segments of the larval abdomen; however, only those associated with segments AVIII–AX were actually used in ambulation by anchoring to the host plant. These ampullae always function with the true legs during movement. Our study unveils ambiguities in homology and terminology of abdominal ambulatory structures that are relevant to discussions of chrysomelid characters and phylogeny.

The adult female, larva, and pupa of Strategus fascinus Burmeister (Scarabaeidae: Dynastinae: Oryctini) are described for the first time based on specimens from Colombia. A key to the known third-stage larvae of Strategus species is included. The biology and distribution of S. fascinus, are discussed.