Journal of Insect Science最新文献

The Canary Islands is a Macaronesian volcanic archipelago with a depauperate community of three species of Kalotermitidae, including Kalotermes dispar. A total of 54 Kalotermes colonies were collected from Gran Canaria, Tenerife, La Gomera, La Palma, and El Hierro islands. Soldiers and imagos were morphologically examined and sequenced for four mitochondrial markers. Although morphological differences could not be detected, phylogenetic analysis of both cox1/tRNA/cox2 and rrnL markers revealed two distinct clades of K. dispar, suggesting cryptic diversity. The diversification within the Canary Kalotermes lineage most likely occurred around 7.5 Mya, while the divergence within the two clades was reconstructed at about 3.6 Mya and 1.9 Mya. Kalotermes approximatus from the southeastern Nearctic constitutes a sister to the Canary Kalotermes, while the Palearctic K. flavicollis, K. italicus, and K. phoenicae form a separate clade. It is hypothesized that a faunal exchange of Kalotermes from the Nearctic to the Canary Islands occurred via transoceanic rafting during the mid-Miocene.

Tephritis angustipennis (Diptera: Tephritidae) and Campiglossa loewiana (Diptera: Tephritidae) are phytophagous pests in China. Their damage has significantly impacted the collection and cultivation of germplasm resources of native Asteraceae plants. However, the genetic characteristics and structure of their population are unclear. This study focused on the highly damaging species of T. angustipennis and C. loewiana collected from the three-river source region (TRSR). We amplified the mitochondrial cytochrome C oxidase subunit I (mtCOI) gene sequences of these pests collected from this area and compared them with COI sequences from GenBank. We also analyzed their genetic diversity and structure. In T. angustipennis, 5 haplotypes were identified from 5 geographic locations; the genetic differentiation between France population FRPY (from Nylandia, Uusimaa) and China populations GLJZ (from Dehe Longwa Village, Maqin County), GLDR (from Zhique Village, Dari County), and GLMQ (from Rijin Village, Maqin County) was the strongest. GLJZ exhibited strong genetic differentiation from GLDR and GLMQ, with relatively low gene flow. For C. loewiana, 11 haplotypes were identified from 5 geographic locations; the genetic differentiation between the Chinese population GLMQ-YY (from Yangyu Forest Farm, Maqin County) and Finnish population FDNL (from Nylandia, Uusimaa) was the strongest, with relatively low gene flow, possibly due to geographical barriers in the Qinghai-Tibet plateau. Only 1 haplotype was identified across GLDR, GLMQ, and GLBM. High gene flow between distant locations indicates that human activities or wind dispersal may facilitate the dispersal of fruit flies and across different geographic. Geostatistical analysis suggested a recent population expansion of these 2 species in TRSR. Our findings provide technical references for identifying pests in the TRSR region and theoretical support for managing resistance, monitoring pest occurrences, analyzing environmental adaptability, and formulating biological control strategies for Tephritidae pests on Asteraceae plants.

Bemisia tabaci New World (NW) (Gennadius) (Hemiptera: Aleyrodidae), a whitefly in the B. tabaci species complex, is polyphagous on many plant species. Yet, it has been displaced, albeit not entirely, by other whitefly species. Potential causes could include issues with adaptation, feeding, and the colonization of new-hosts; however, insights that would help clarify these possibilities are lacking. Here, we sought to address these gaps by performing electropenetrography (EPG) recordings of NW whiteflies, designated "Napus" and "Rapa," reared on 2 colony hosts, Brassica napus and B. rapa, respectively. Analysis of 17 probing and pathway (pw) phase-related EPG variables revealed that the whiteflies exhibited unique probing behaviors on their respective colony hosts, with some deterrence being encountered on B. rapa. Upon switching to B. rapa and B. napus, the probing patterns of Napus and Rapa whiteflies, respectively, adapted quickly to these new-hosts to resemble that of whiteflies feeding on their colony hosts. Results for 3 of the EPG variables suggested that B. rapa's deterrence against Napus whitefly was significant prior to the phloem phase. This also suggested that adaptation by Rapa whitefly improved its pw probing on B. rapa. Based on analysis of 24 phloem phase-related EPG variables, Napus and Rapa whiteflies performed equally well once they entered phloem phase and exhibited comparable phloem acceptability on both the colony- and new-hosts. These findings demonstrate that NW whiteflies reared on a colony host are highly adaptable to feeding on a new host despite encountering some deterrence during the nonphloem phases in B. rapa plant.

Ascogaster mimetica Viereck is an egg-larval parasitoid that targets Sparganothis sulfureana Clemens, a major cranberry pest in North America. While previous studies have shown that other Ascogaster species respond to cues from their hosts' eggs, it remains unknown whether A. mimetica utilizes these cues to recognize S. sulfureana. We hypothesized that female A. mimetica recognizes S. sulfureana from another cranberry pest, Choristoneura parallela Robinson, based on the presence of surface cues on eggs. To test this, we observed female A. mimetica behavior when exposed to eggs from its host, S. sulfureana; a nonhost, C. parallela; and eggs of S. sulfureana that were washed clean with hexane. Additionally, we tracked parasitism rates in each group. Our results revealed that A. mimetica spent 9.5 times longer walking when exposed to C. parallela eggs and 6 times longer when exposed to hexane-washed S. sulfureana eggs compared to unwashed S. sulfureana eggs. Also, A. mimetica spent 3 times longer grooming when exposed to hexane-washed than unwashed S. sulfureana eggs. In contrast, females spent 6 and 18 times longer drumming and probing/ovipositing on unwashed S. sulfureana eggs than on C. parallela eggs and 5 times longer probing/ovipositing on unwashed S. sulfureana eggs than on hexane-washed S. sulfureana eggs. Higher parasitism rates were observed from unwashed S. sulfureana eggs compared to those from C. parallela eggs and hexane-washed S. sulfureana eggs. Our findings suggest that the presence of egg surface cues, like scales, of S. sulfureana likely plays a crucial role in host acceptance and parasitism success for A. mimetica.

Pairs of adult male crickets, Gryllus bimaculatus, fight and immediately determine winner and loser statuses. The winner male repeatedly produces an aggressive (rival) song by rubbing his forewings together. In this study, I removed the plectrum, a sound-producing structure in the forewing, from male crickets and measured their brain serotonin (5-hydroxytryptamine: 5-HT) levels immediately after a 10-min aggressive interaction. Pairs of plectrum-removed males fought and established clear winner-loser relationships, like the case of intact males. The plectrum-removed winner males frequently rubbed their forewings together, but were unable to produce song. Aggressive interaction reduced significantly brain 5-HT levels in the plectrum-removed males, regardless of their winner and loser statuses. Furthermore, the reduction of brain 5-HT was detected primarily in the central body, a group of neuropils spanning the midline of the brain. In contrast, in pairs of intact males, aggressive interaction reduced brain 5-HT levels in the loser males, but not in the winner males. Plectrum removal alone did not affect the brain's 5-HT levels. These results suggest that aggressive song emitted by the winner male cricket prevents the reduction of 5-HT levels in his own brain, especially in the central body.

The Entomological Society of America (ESA) Student Debates is an annual student competition at the ESA Annual Meeting organized by Student Debates Subcommittee (SDS) members of the ESA Student Affairs Committee. In conjunction with the 2023 ESA Annual Meeting theme, 'Insects and influence: Advancing entomology's impact on people and policy', the theme of this year's student debate was 'Addressing emerging issues in entomology'. With the aid of ESA membership, the SDS selected the following debate topics: (1) Should disclosure of artificial intelligence large language models in scientific writing always be required? and (2) Is it more important to prioritize honey bee or native pollinator health for long-term food security within North America? Four student teams from across the nation, composed of 3-5 student members and a professional advisor, were assigned a topic and stance. Over the course of 5 months, all team members researched and prepared for their assigned topic before debating live with an opposing team at the 2023 ESA Annual Meeting in National Harbor, Maryland. SDS members additionally prepared and presented introductions for each debate topic to provide unbiased backgrounds to the judges and audience for context in assessing teams' arguments. The result was an engaging discussion between our teams, judges, and audience members on emerging issues facing entomology and its impact on people and policy, such as scientific communication and food security, that brought attention to the complexities involved when debating topics concerning insects and influence.

Invasive fruit flies (Diptera: Tephritidae) pose a serious threat to the production and export of many commercially important fruits and vegetables. Detection of the agricultural pests Bactrocera dorsalis (Hendel) and Zeugodacus cucurbitae (Coquillett) relies heavily on traps baited with male-specific attractants. For B. dorsalis, traps are typically baited with liquid methyl eugenol (ME), and for Z. cucurbitae, traps are baited with liquid cue-lure (CL). Operating large-scale trapping networks is costly, consequently, there is much interest in identifying ways to maintain network sensitivity while reducing costs. One cost-cutting approach is the possibility of combining different male lures in the same dispenser, thus reducing the number of traps requiring servicing. The chief objective of this study was to compare captures of B. dorsalis and Z. cucurbitae males in Jackson traps baited with polymeric wafers impregnated with both ME and raspberry ketone (RK, a hydrolyzed form of CL) versus traps baited with liquid ME or CL freshly applied to cotton wicks. Captures were measured when the ME/RK wafers had been weathered for 12, 18, or 24 wk. Captures of B. dorsalis and Z. cucurbitae males were similar between fresh lure and weathered wafers over all trapping periods, with a single exception apparently due to the lessened potency of the associated killing agent. The residual amount and release rate of ME and RK from the wafers were also measured to examine possible relationships between wafer chemistry and trap catch. The possible implications of the present results to area-wide trapping programs are discussed.

Little is known about winter-season parasitism of eggs of the corn leafhopper Dalbulus maidis DeLong (Hemiptera: Cicadellidae), an important pest of maize throughout the Americas. Our study, conducted in Mexico, aimed to characterize winter-season parasitism of corn leafhopper eggs on maize crops cultivated with drip irrigation and on wild grasses that grow on the edges of maize crops when maize is not present. Maize leaves baited with D. maidis eggs were used to trap the egg parasitoids in the field. In the first year (2022), parasitism of D. maidis eggs was investigated in maize fields planted contiguously on different dates (asynchronous planting). In the second year (2023), parasitism of D. maidis eggs was evaluated in edge grasses and in adjacent maize crops planted on the same date (synchronous). The highest percentage of parasitism (53%), percentage of emergence, and total abundance of egg parasitoids were found in asynchronous maize fields. Here, Anagrus virlai Triapitsyn (Hymenoptera: Mymaridae), Paracentrobia subflava (Girault) (Hymenoptera: Trichogrammatidae), and Pseudoligosita sp. (Hymenoptera: Trichogrammatidae) wasps were found parasitizing the D. maidis eggs, with P. subflava being the most abundant. In wild edge grasses, only P. subflava was found, showing low levels of parasitism, while in synchronous maize, P. subflava increased its percentage of parasitism (up to 37%), percentage of emergence, and abundance, during winter. These results suggest that P. subflava acts as an efficient biological control agent of D. maidis in irrigation-grown maize crops during the winter season, and that edge grasses are overwinter habitats for P. subflava.

Declines in pollinating insects have been linked to changes in land cover, affecting the availability of nesting sites and floral resources. Our study is the first analysis of changes in pollen load composition of 2 mining bees, Andrena barbilabris (Kirby) and Andrena flavipes (Panzer) (Hymenoptera: Andrenidae), at the same sites in central England, over 75 years. This provides a unique opportunity to remove spatial variation and review temporal changes in pollen diet within the context of landscape change. We analyzed modern-day pollen load composition for these species and compared it with historical data from the same sites. We then examined potential links between land-use change and the bees' diets. Both bees showed dietary flexibility and lower diet breadth for A. barbilabris, and the bees' foraging strategies appear to have changed. Andrena flavipes collected more pollen taxa in a single load, while A. barbilabris appeared to source pollen from greater distances. Landscape changes at the studied sites have affected the nutritional environment for these bees. Our findings are supported by an existing assessment of floral resources, which found floral diversity has decreased overall in both the habitats used by these bees. However, more research is needed on the nutritional content of pollens used by these bees, both now and historically, to estimate how pollen diversity has changed. The bee's-eye view underlines the importance of understanding how species respond to local changes so that effective conservation strategies can be developed.