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Vespa mandarinia Smith 1852 is a semi-specialized predator of other social Hymenoptera and one of the two largest species of Vespa . Several individuals of this predatory wasp were detected in Canada and the United States in 2019, including an entire nest that was located and destroyed on Vancouver Island, British Columbia. The Washington State Department of Agriculture and the United States Department of Agriculture’s Animal and Plant Health Inspection Service have collaborated to survey Washington State for V. mandarinia since 2020, using traps staffed by agency personnel, collaborators from local governments and nongovernmental organizations, and the general public. Trap data and public reports were used to select sites for live-trapping or net surveys, and live hornets captured in these efforts were subsequently collected and fitted with radio tags to locate nests. The survey ultimately led to the discovery of a V. mandarinia nest in October 2020, and three nests in August and September 2021. All of the nests were located within in red alder trees ( Alnus rubra ), with one just above the ground in a standing dead tree, and the other three in cavities ~2 to 5 meters above the ground in living trees. The number of combs in each nest varied between four and ten, cells between 418 and 1,329, and total hornets per nest between 449 and 1,474 (including immature and mature stages). Together, the four nests indicate an incipient population of V. mandarinia in the Cascadia region, and ongoing action by local, state, provincial, and federal governments, and residents of both countries is required to avoid the establishment of this exotic species in the region.

Species-specific behavior-modifying chemicals have been used for more than 50 years for monitoring and management of insect pests of agriculture and human health. Elaterid beetle larvae are among insect pests in soil that are increasingly problematic, in part due to the lack of effective management strategies. However, little is known about the insect-produced chemicals that mediate the reproductive behavior of these pests. We used chemical and behavioral studies to identify, synthesize, and field test the sex attractant pheromone of adults of Melanotus communis , commonly called the corn wireworm, the larvae of which are economically important pests of U.S. crops. Our results indicated that a single female-produced chemical, 13-tetradecenyl acetate, was strongly attractive to conspecific male beetles, and did not appear to attract other species. In field evaluations, male M. communis exhibited a dose-dependent response to this compound. In a trial comparing different slow-release dispensers, a small rubber septum impregnated with the chemical was as effective as and easier to use than a plastic bag dispenser. Given that the sex attractant of this insect consists of a single compound that can be readily synthesized, its development for monitoring and management of the corn wireworm may be economically feasible.

Females of two click beetle species , Cardiophorus tenebrosus and C. edwardsi (Coleoptera: Elateridae), produce methyl (3 R ,6 E )-2,3-dihydrofarnesoate as their sex pheromone. We had serendipitously discovered that males of both species were also strongly attracted to ( R )-fuscumol acetate (( E )-6,10-dimethylundeca-5,9-dien-2-yl acetate), a known longhorned beetle (Coleoptera: Cerambycidae) pheromone, due to its structural similarities to the click beetle pheromone. To further investigate the specificity of the responses of Cardiophorus males, additional analogs with different chain lengths and structural relationships compared to the natural pheromone were synthesized and tested. In field and electroantennogram bioassays, only fuscumol propionate (( E )-6,10-dimethylundeca-5,9-dien-2-yl propionate) elicited strong responses from Cardiophorus males, indicating that they were able to distinguish chain length and spatial relationships between the structural elements. In field trials, C. tenebrosus males were attracted equally to the analog and their natural pheromone, but the pheromone elicited stronger antennal responses from males. In contrast, traps baited with fuscumol propionate caught approximately 26 times as many C. edwardsi males compared to traps baited with the natural pheromone, although the analog elicited significantly smaller antennal responses from C. edwardsi males. Thus, in terms of behavioral responses, fuscumol propionate appears to be acting as a hyperactive pheromone mimic, a phenomenon which has rarely been observed in insect semiochemistry.

Hexanoic acid, 1-octanol, 1,8-octanediol, octyl hexanoate, 1,8-octanediol monohexanoate, and 1,8-octanediol dihexanoate were identified in headspace volatiles collected from the crushed abdomen of a female click beetle of the species Parallelostethus attenuatus (Say) (Elaterinae, tribe Elaterini). In field trials carried out in Illinois, South Carolina, North Carolina, and Virginia, adult male beetles were strongly attracted to 1,8-octanediol dihexanoate alone. Blends of the dihexanoate with one or more of the other compounds proved to be less attractive than the dihexanoate alone, suggesting that the pheromone of this species may consist of a single compound. The symmetrical diester structure of the pheromone is a novel natural product and appears to be structurally unique among insect pheromones.

Four species of Limonius wireworms (Coleoptera: Elateridae), L. californicus, L. canus, L. infuscatus and L. agonus, are serious crop pests in North America. Limoniic acid, (E)-4-ethyloct-4-enoic acid, has been reported as a sex pheromone component of female L. californicus and L. canus, and a sex attractant for male L. infuscatus. In the same study, both limoniic acid and the analog (E)-5-ethyloct-4-enoic acid were highly attractive in field experiments. Moreover, six carboxylic acids in headspace volatiles of Limonius females elicited responses from male antennae but were not tested for behavioral activity. Here, we report trap catch data of Limonius spp. obtained in field experiments at 27 sites across North America. All four Limonius species were attracted to limoniic acid and to the analog but not to the carboxylic acids. Adding these carboxylic acids to limoniic acid, or to the analog, reduced its attractiveness. In dose–response studies, trap lures containing 0.4 mg or 4 mg of limoniic acid afforded large captures of L. californicus and L. infuscatus. Neither limoniic acid nor the analog were deterrent to other elaterid pest species. The broad attractiveness of limoniic acid to Limonius spp., and its non-deterrent effect on heterogeners, may facilitate the development of generic pheromone-based monitoring and management tools for multiple click beetle species.

To date, all known or suspected pheromones of click beetles (Coleoptera: Elateridae) have been identified solely from species native to Europe and Asia; reports of identifications from North American species dating from the 1970s have since proven to be incorrect. While conducting bioassays of pheromones of a longhorned beetle (Coleoptera: Cerambycidae), we serendipitously discovered that males of Cardiophorus tenebrosus L. and Cardiophorus edwardsi Horn were specifically attracted to the cerambycid pheromone fuscumol acetate, (E)-6,10-dimethylundeca-5,9-dien-2-yl acetate, suggesting that this compound might also be a sex pheromone for the two Cardiophorus species. Further field bioassays and electrophysiological assays with the enantiomers of fuscumol acetate determined that males were specifically attracted by the (R)-enantiomer. However, subsequent analyses of extracts of volatiles from female C. tenebrosus and C. edwardsi showed that the females actually produced a different compound, which was identified as (3R,6E)-3,7,11-trimethyl-6,10-dodecadienoic acid methyl ester (methyl (3R,6E)-2,3-dihydrofarnesoate). In field trials, both the racemate and the (R)-enantiomer of the pheromone attracted similar numbers of male beetles, suggesting that the (S)-enantiomer was not interfering with responses to the insect-produced (R)-enantiomer. This report constitutes the first conclusive identification of sex pheromones for any North American click beetle species. Possible reasons for the strong and specific attraction of males to fuscumol acetate, which is markedly different in structure to the actual pheromone, are discussed.

Insect pheromones have rarely been exploited in surveys or studies of rare and endangered species, despite their potential as effective and highly selective attractants for target species. Here, we report the identification, synthesis, and field bioassays of a male-produced aggregation-sex pheromone blend of a rare false click beetle species endemic to southern California, Dohrn’s elegant eucnemid beetle, Palaeoxenus dohrni Horn (Coleoptera: Eucnemidae). This species is the only extant species in its genus and subfamily. Analyses of extracts of headspace volatiles collected from adult beetles revealed several male-specific compounds. Two of these compounds, identified as (E)-2-nonen-4-one and (R)-2-nonanol, elicited electroantennographic responses from antennae of beetles of both sexes. In field bioassays, a blend of the two compounds attracted both sexes, whereas the individual compounds were not attractive. The identification of an attractant pheromone should provide a useful tool for bioconservation and ecological studies of this iconic species.

We report the identification of p-mentha-1,3-dien-8-ol, an unstable monoterpene alcohol, as a male-produced aggregation-sex pheromone component of the cerambycid beetle Paranoplium gracile (Leconte) (subfamily Cerambycinae, tribe Oemini), a species endemic to California. Headspace volatiles from live males contained a blend of nine cyclic terpenoids that were not detected in analogous samples from females. Volatiles produced by male Eudistenia costipennis Fall, also in the tribe Oemini, contained the same suite of nine compounds. Four compounds, dehydro-p-cymene, p-mentha-1,3-dien-8-ol, p,α,α-trimethylbenzyl alcohol, and an unidentified compound were found to elicit responses from antennae of P. gracile females in coupled gas chromatography-electroantennogram detection (GC-EAD) assays, whereas only p-mentha-1,3-dien-8-ol elicited responses from antennae of males. In field assays, p-mentha-1,3-dien-8-ol stabilized with the antioxidant butylated hydroxytoluene (BHT) attracted P. gracile of both sexes, indicating it functions as an aggregation-sex pheromone, as with other pheromones identified from its subfamily, the Cerambycinae. Adding four of the other compounds found in headspace samples to the dienol lure had no effect on attraction. Because of the instability of p-mentha-1,3-dien-8-ol, it seems likely that at least some of the compounds seen in the extracts of volatiles from both species are artefacts, rather than being components of the pheromone.

Phenotypic polymorphism in rattlesnake venoms is well-documented, with a dichotomy between hemorrhagic (Type I) and neurotoxic (Type II) venoms. In South America, the Type II phenotype is predominant; however, evidence of Type I venom in Crotalus durissus ruruima raises concerns about the efficacy of the Crotalus antivenom, which is prepared only with Type II venoms. Consequently, the Bothrops-Crotalus antivenom has been proposed as an alternative treatment for envenomation by Type I venoms. This study characterizes the dichotomy of C. d. ruruima venom by analyzing the structure of isoforms differentially expressed in Type I and Type II venoms, assessing their biological activities, and evaluating the implications for snakebite clinical management in Roraima State (northern Brazil). Four toxins were differentially expressed between Type I and Type II venoms: two PIII-class SVMPs, predominantly found in Type I venoms, associated with proteolytic and hemorrhagic activity; and two PLA2s, corresponding to Crotoxin A and B chains, prevalent in Type II venoms and related to elevated phospholipase A2 activity, myotoxicity, and increased lethality. The structure of Crotoxin chains was well conserved compared to C. d. terrificus Crotoxin. However, the SVMP sequences exhibited multiple substitutions in functional and immunoreactive regions compared to Bothropasin, resulting in low hemorrhagic activity and limited reactivity/neutralization by the Bothrops antivenom. Conversely, the Crotalus antivenom reacted with high antibody titer and neutralized all activities of both venom subtypes, except for the low hemorrhagic activity induced by Type I venoms. The efficacy of Bothrops antivenom in snakebites caused by rattlesnakes with Type I venoms remains uncertain. We advocate for a clinical study in Roraima to assess patient outcomes and benefits of Bothrops-Crotalus versus Crotalus antivenoms for these accidents. Meanwhile, administering Bothrops-Crotalus antivenom may be acceptable; however, caution is needed regarding the use of heterologous Bothrops antibodies, which have limited efficacy in treating Crotalus envenomation.

Tidal marshes are threatened coastal ecosystems known for their capacity to store large amounts of carbon in their water-logged soils. Accurate quantification and mapping of global tidal marshes soil organic carbon (SOC) stocks is of considerable value to conservation efforts. Here, we used training data from 3710 unique locations, landscape-level environmental drivers and a global tidal marsh extent map to produce a global, spatially explicit map of SOC storage in tidal marshes at 30 m resolution. Here we show the total global SOC stock to 1 m to be 1.44 Pg C, with a third of this value stored in the United States of America. On average, SOC in tidal marshes’ 0–30 and 30–100 cm soil layers are estimated at 83.1 Mg C ha −1 (average predicted error 44.8 Mg C ha −1 ) and 185.3 Mg C ha −1 (average predicted error 105.7 Mg C ha −1 ), respectively. A new study shows the total global SOC stock of 1 m in the world’s tidal marshes to be 1.44 Pg C. On average, SOC in tidal marshes’ 0–30 cm and 30–100 cm soil layers are estimated at 83.1 Mg C ha −1 and 185.3 Mg C ha −1 , respectively.