The long coevolutionary history between sunflowers (Helianthus annuus, Asterales: Asteraceae) and arthropods in the northern Great Plains has resulted in a commonly grown oilseed crop that harbors a large diversity of insects. A bioinventory of foliar and subterranean arthropods was performed in 22 sunflower fields over a period of three site years in central and eastern South Dakota. Overall, 467 morphospecies were collected. From foliage, 15 arthropod orders were observed. Those containing the greatest species diversity were Hymenoptera, Coleoptera, Hemiptera, Diptera and Araneae with 80; 53; 53; 40 and 30 morphospecies each, respectively. Subterranean arthropods from 19 orders were collected. The five orders containing the highest number of morphospecies were Coleoptera, Hymenoptera, Hemiptera, Araneae and Diptera containing 77; 17; 14; 11 and nine morphospecies respectively. Although bioinventories can be expensive and time consuming, information gathered from them has many uses, including efforts to assess the implications of pesticide use, wildlife conservation, land use- and climate-change on community structure in sunflowers.

There is a need for safe and consistent management of the brown recluse spider, Loxosceles reclusa Gertsch & Mulaik, a toxic spider found in homes throughout Kansas and the south and central United States. This study examined the efficacy of two general-use insecticides with brown recluse on their labels, .05% bifenthrin with 0.0125% zeta-cypermethrin (Insecticide 1), and 0.03% lambda-cyhalothrin (Insecticide 2) against the brown recluse spider at three times post-treatment, 1, 24, and 96 hr, and on two substrates, carpet and tile. This study also evaluated the efficacy of these insecticides on spiders exposed for three lengths of time, 0.5, 1, and 30 min on each substrate. Results indicate that Insecticide 2 had better overall residual efficacy than Insecticide 1. In addition, in one experiment efficacy was better when the spiders were exposed on tile surfaces. Residual efficacy for Insecticide 2 was greater one and 24 hr after application but decreased at 96 hr. The efficacy of Insecticide 1 was not affected by length of time between application and spider exposure, on either surface. Spider mortality was also significantly impacted by the length of time the spiders were exposed to the treated surface. There was no significant difference in spider mortality with either insecticide at 0.5 or 1 min exposure. However, exposures of 30 min led to significantly greater spider mortality for both insecticides, and on both substrates. 100% mortality occurred when spiders were exposed to either insecticide for 30 min on tile. This study also examined the effect of sticky traps placed in homes and in combination with an insecticide application of 0.03% lambda-cyhalothrin. The sticky traps alone did not reduce the infestation but, in combination with one insecticide treatment, spider trap numbers decreased over a 4 wk period.

Most insects must accumulate certain metabolites before entering diapause by virtue of photoperiodic regulation. Photoperiods influence diapause beyond the maternal generation in Cotesia vestalis (Haliday) (Hymenoptera: Braconidae), which is one of the most important larval endoparasitoid of Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae). The accumulation of metabolites in the non-diapausing prepupae, adults, and eggs (before and after oviposition) in progeny from C. vestalis cultures reared at 25°C under three photoperiods (8:16, 12:12, and 16:8 (L:D) hr), along with diapausing prepupae were measured to investigate the effects of photoperiod on the accumulation of metabolites during diapause induction. Compared with those of non-diapausing prepupae, free water, trehalose, total lipid titer, and total polyol contents in diapausing prepupae showed no significant differences; but weight, bound water, total sugar, glycogen, triglyceride, and protein contents were significantly higher. Under 8 hr short days, non-diapausing prepupae and adult females were significantly heavier, and held more bound water content, however, had less free water content than those under 16 hr long days; during diapause induction from maternal generation to progeny, the variation trends of triglyceride and protein contents were irregular, such as at one stage the contents under 8 hr short lights were higher, at another stage were lower, and there was even no difference at the other stage with those under long light. Total polyol (except at prepupal stage) increased with the increase of light period, but glycogen contents increased as the light period was reduced from prepupal, adult stages to egg stages (before and after oviposition) in progeny. These results revealed that in C. vestalis, the parasitoids might start accumulating glycogen, rather than other metabolites, before entering diapause, even at maternal generation influenced by short photoperiod. Meanwhile, lower total polyol content, and higher bound water content, dry weight under short light may be prepared for surviving adverse environments (desiccation and cold) after diapause. The condition experienced by maternal generation must be concerned during diapause induction.

Acetylcholinesterase (AChE, EC 3.1.1.7), which is encoded by the ace gene, is a key enzyme in both cholinergic system and other non-neuronal tissues. AChE is the target of organophosphates (OP) and carbamates (CA) insecticides. Although AChEs have been extensively studied in lepidopteran pests, no research has been carried out on butterflies, a major subgroup in Lepidoptera. In this study, we cloned two ace genes (Mcace1 and Mcace2) from the Glanville fritillary butterfly (Melitaea cinxia, Lepidoptera: Nymphalidae). The full-length cDNA of Mcace1 was 2433bp, containing a 2073bp ORF encoding 690 amino acids, a 227bp 5’-untranslated region (5’-UTR), and a 133bp 3’-UTR with a poly(A) tail. The cDNA of Mcace2 was 2400bp in length, containing a 1911bp ORF encoding 636 amino acids, a 368bp 5’-UTR, and a 121bp 3’-UTR with a poly(A) tail. Both the deduced proteins, McAChE1 and McAChE2, possess typical features of AChE family, such as catalytic triad, acyl pocket and choline-binding site. Phylogenetic analysis indicated that McAChE1 and McAChE2 exhibited the highest identity to the AChE1 and AChE2 of moths, respectively. We compared the amino acids at the sites where substitution may result in insecticide resistance between McACHEs and the earlier reported AChEs, and found that no amino acid substitution related to insecticide resistance occurs in either McAChE1 or McAChE2. These implied that both McAChE1 and McAChE2 may be sensitive to OP and CA insecticides. The result is compatible with our expectation as no insecticides were used in the habitat of the Glanville fritillary.

This third segment in the Beetles of Peru follows from beetle families presented in preceding issues of this journal. This segment presents two chrysomeloid families, Megalopodinae and Chrysomelidae, and Riphiphoridae, Cantharidae, Nosodendridae, Dermestidae, and Bostrichidae. Chrysomelidae in Peru number 1724 species, making it the most speciose of all the beetle families in Peru. More beetle families will be presented in upcoming issues of this journal.