我国五种重要吉丁虫学名订正及再描述(鞘翅目:吉丁甲科)

【目的】吉丁甲类昆虫是我国重要的农林害虫,但多年来国内文献资料包括一些高校教科书中存在诸多学名问题,如国际上已修订的学名国内长期未更新、错误鉴定、同物异名、种名误记等。本文对我国5种重要吉丁虫进行学名修订。【方法】本研究基于多年来积累的吉丁虫标本,通过比对文献以及与国内外同行讨论、标本检视、解剖生殖器、生物学危害特征观察等方法,对我国5种重要吉丁虫的形态和生物学特征进行比较和分析。【结果】重新描述了5种重要吉丁虫的主要形态特征,并记述了其分布范围、寄主植物、危害习性等,明确了金缘吉丁、杨十斑吉丁、杨五星吉丁、核桃缘吉丁和柳窄吉丁的正确学名分别为Lamprodila limbata(Gebler),Trachypteris picta picta(Pallas),Capnodis miliaris metallica Ballion,Meliboeus ohbayashii primoriensis(Alexeev)和Agrilus pekinensis pekinensis Obenberger。【结论】本研究厘订了我国吉丁甲文献中长期存在的一些学名错误,对解决我国部分吉丁甲类昆虫在研究和防治应用中的学名混乱问题具有重要意义。     

中国窄吉丁属二新种及一新记录种记述(鞘翅目:吉丁科)

记述脊窄吉丁种团Agrilus japanocarinatus species-group 2新种:长脊窄吉丁Agrilus longicarinus sp.nov.(广东)和林氏窄吉丁 A.lini sp.nov.(海南).首次记录了阿氏窄吉丁 A.arsenevi Jendek,2009.编制了该种团的中国种检索表...     

我国新上升的四种吉丁甲科蛀干害虫记述

【目的】为准确识别和鉴定目前国内新上升的4种吉丁甲科蛀干害虫,便于生产上对其开展有效的监测和防治。【方法】将收集到的标本通过比对文献以及与国内外同行讨论、标本检视、生物学危害特征观察等方法进行比较和分析。【结果】对中国新记录的沙蒿尖翅吉丁Sphenoptera sp.和柠条窄吉丁Agrilus sp.鉴定到种,对栎窄吉丁Agrilus cyaneoniger Saunders体色多型现象进行了描述,对弗氏窄吉丁Agrilus fleischeri Obenberger的形态特征进行了再描述,并根据4种吉丁甲科害虫生物学特性和危害特征提出了相应的防治建议。【结论】沙蒿尖翅吉丁学名为Sphenoptera canescens Motschulsky,柠条窄吉丁学名为Agrilus unguiculosus Obenberger;栎窄吉丁体二色型主要分布于中国东北,南方分布的主要为全体黑色型;弗氏窄吉丁的分布范围在不断扩大。对这些具有潜在高风险的蛀干类吉丁甲害虫,加强检疫和营林措施防止其扩散传播是非常必要的,保护天敌有助于抑制其种群数量快速上升,局部暴发时采取化学防治也是必要的应急手段。     

白蜡窄吉丁幼虫及其天敌在空间格局上的关系

调查了白蜡窄吉丁幼虫与其寄生性天敌白蜡吉丁柄腹茧蜂和捕食性天敌啄木鸟啄食白蜡窄吉丁的啄痕在空间格局上的规律.结果表明,在林间水平方向上,白蜡窄吉丁幼虫呈聚集分布,白蜡吉丁柄腹茧蜂和啄木鸟的啄痕也表现为聚集分布;在垂直方向上,白蜡窄吉丁幼虫分布于地面至3.37m以下的树干,主要集中于1.0m左右的主干,天敌也集中在此范围内活动.     

白蜡吉丁柄腹茧蜂的羽化和产卵与寄主之间的关系

白蜡窄吉丁是危害白蜡属树木的一种重要蛀干害虫,因其幼虫期高度的隐蔽性生活而极难检测和防治.白蜡吉丁柄腹茧蜂是新发现外寄生于白蜡窄吉丁幼虫的优势天敌种,对寄主害虫的控制作用较强,具有良好的生物防治利用前景.研究调查了白蜡吉丁柄腹茧蜂及其寄主白蜡窄吉丁越冬代成虫羽化的时序差异、不同时期林间的寄生率、寄主密度与寄生率的关系以及寄主幼虫大小与茧蜂产卵量的关系.结果表明,越冬后白蜡吉丁柄腹茧蜂的羽化时间比其寄主害虫白蜡窄吉丁的羽化要晚1个多月.2003年白蜡吉丁柄腹茧蜂越冬代成虫的羽化从6月中旬持续到8月中旬,羽化高峰期在7月份;寄主白蜡窄吉丁的羽化期在5月中下旬.2004年白蜡吉丁柄腹茧蜂越冬代成虫的羽化从5月下旬持续到7月下旬,羽化高峰期在6月下旬至7月上旬;寄主羽化期在4月中旬至5月中旬（室内）.越冬后天敌的羽化时间刚好适应最早寄主发育到可供寄生的龄期,这是二者长期协同进化的结果,也表明白蜡吉丁柄腹茧蜂很可能是一种专性寄生蜂.林间白蜡吉丁柄腹茧蜂对白蜡窄吉丁幼虫的自然寄生率随着时间的推移总体上是逐步上升的.自然条件下茧蜂决定是否产卵与寄主幼虫的大小即龄期有关,它仅在前胸宽和体宽1.5 mm、体长12 mm以上,即3～4龄的寄主幼虫体表产卵,但只要接受寄主并产卵,不同龄期寄主幼虫上的产卵量无显著的差异.     

利用改进方法预测白蜡窄吉丁在国内的适生区

白蜡窄吉丁Agrilus planipennis在我国正由一种本土次要害虫上升为主要害虫,明确其可能的适生范围、指导各地区及早采取防范措施非常必要.本研究考虑气候、寄主树种分布、气候-寄主树种分布综合数据分别构建模型进行白蜡窄吉丁潜在适生区预测和分析,以期建立一种能够更加准确预测钻蛀类害虫潜在分布区的改进方法.除气候条件外,寄主树种的分布是影响白蜡窄吉丁分布的重要因素,应参与蛀干类昆虫适生区的预测.将非生物因素(气候)以及生物因素(寄主树种分布)作为单一变量时得到的预测结果进行叠加,更加符合白蜡窄吉丁分布现状和生存特性.白蜡窄吉丁在我国仍有继续向中部、南部等未发生区传播扩散的风险,限制敏感寄主树种的栽植是有效防范该虫危害的重要手段.     

白蜡窄吉丁气味结合蛋白AplaOBP3的免疫定位及配体结合特性

【目的】本研究旨在解析白蜡窄吉丁Agrilus planipennis气味结合蛋白AplaOBP3在触角中的定位及配体结合特性,同时比较AplaOBP3与已报道的AplaOBP1和AplaOBP2的功能异同。【方法】原核表达白蜡窄吉丁气味结合蛋白AplaOBP3,制备多克隆抗体并进行Western blot检测;采用免疫组织化学技术在白蜡窄吉丁触角感器中对AplaOBP3的表达进行定位;通过荧光竞争结合实验分析AplaOBP3重组蛋白与58种化合物的结合特性,并与前期报道的白蜡窄吉丁AplaOBP1和AplaOBP2蛋白的配体结合特性进行比较。【结果】原核表达系统中成功表达AplaOBP3重组蛋白;免疫定位结果显示AplaOBP3在白蜡窄吉丁触角的锥形感器类型I中表达。荧光竞争结合实验结果表明,重组AplaOBP3蛋白与反-2-己烯醛、苯甲醛、4′-乙基苯乙酮、β-紫罗兰酮和罗勒烯具有强的结合能力,其解离常数KD值分别为6.20,4.03,5.24,1.72和4.83 μmol/L。AplaOBP3与AplaOBP2具有相似的表达及配体结合特性。【结论】白蜡窄吉丁气味结合蛋白AplaOBP3与AplaOBP2具有相似的表达及配体结合特性,它们可能共同参与白蜡窄吉丁的嗅觉感受,在白蜡窄吉丁寄主定位过程中发挥作用。     

基于特定时间调查数据组建的白蜡窄吉丁种群生命表

为了探明影响白蜡窄吉丁Agrilus planipennis Fairmaire自然种群变化的关键因子, 本研究于2010-2011年采用当年秋季和翌年春季两个特定时间调查取样的方法, 组建了天津、 北京和辽宁3个地区白蜡窄吉丁的自然种群生命表。结果显示, 这3个地区白蜡窄吉丁的自然种群数量在今后几年均将呈增长趋势, 但不同地区的增长速率存在较大差异。北京地区白蜡窄吉丁的种群数量增长速率最快（种群趋势指数I=12.9997）, 其次是天津地区（I=12.4388）, 这两个地区的寄主植物相同, 均为绒毛白蜡。增长最慢的是辽宁地区（I=3.6394）, 其寄主植物为水曲柳。另外, 通过3个地区白蜡窄吉丁生命表和排除控制指数可以看出, 天津地区白蜡窄吉丁最主要的致死因子是白蜡吉丁柄腹茧蜂Spathius agrili Yang（种群数量排除控制指数EIPC=1.5382）, 对种群数量变动的贡献最大; 北京地区的是啄木鸟（EIPC=1.4515）, 而辽宁地区白蜡窄吉丁最主要的致死因子是白蜡吉丁卵跳小蜂Oobius agrili Zhang et Huang的寄生作用（EIPC=1.4701）。这些研究结果表明, 寄主植物的差异是影响白蜡窄吉丁自然种群数量变动的主要因素, 同时寄生性天敌白蜡吉丁柄腹茧蜂对种群数量的影响作用也比较大。因此, 实际应用中可以通过培育抗性树种和人工繁育优势天敌等方法对该虫进行有效防治。     

花曲柳窄吉丁的寄主植物范围、危害和防治对策

花曲柳窄吉丁(emerald ash borer, EAB) Agrilus planipennis Fairmaire是木犀科（Oleaceae）梣属Fraxinus植物树木的毁灭性蛀干害虫,目前发现其主要危害欧梣亚属Subgen. Fraxinus欧梣组(Section Fraxinus)和象蜡树组（Section Meliodes）的一些树木种类,如美国白蜡Fraxinus americana、洋白蜡F. pennsylvanica var subintegerrima、绒毛白蜡F. velutina、黑白蜡F. nigra和水曲柳F. mandshurica等。与早期文献上的记载不同,很少发现花曲柳窄吉丁对苦枥木亚属Subgen. Ornus白蜡树组(Section Ornaster)的白蜡树F. chinensis Roxb和花曲柳F. rhynchophylla造成危害。不同寄主白蜡树对花曲柳窄吉丁的敏感性不同,洋白蜡、绒毛白蜡等北美白蜡树种受其危害重于亚洲的水曲柳。这可能是由于长期的适应进化,分布在亚洲地区的梣属寄主树木发展了对花曲柳窄吉丁的抗虫性。中国部分地区发生的花曲柳窄吉丁灾害应该归属于引进的北美白蜡树种对本地害虫敏感所致。在天津、黑龙江、吉林、辽宁、河北、山东、四川、台湾、内蒙古和新疆等省市和自治区,都曾发现花曲柳窄吉丁的危害或分布。白蜡属树木广泛分布于我国除了青藏地区和海南省之外的大部分地区,其中大面积引种北美白蜡树种的北方和西北地区,以及近年来种植发展水曲柳的东北地区都是花曲柳窄吉丁这种毁灭性蛀干害虫的潜在发生地。花曲柳窄吉丁在我国部分地区为检疫性林业害虫,做好检疫是杜绝其扩散蔓延的首要方法。我国局部地区出现花曲柳窄吉丁灾害说明,北美白蜡树种在我国的适应性还需要进行更进一步科学的全面的风险评估,在我国生态建设中应重视利用我国本地的白蜡树种。在花曲柳窄吉丁灾害的治理中,可采用营造混交林以降低蔓延的速度和发挥自然控制能力,加强肥水管理以增强树木的抗虫能力,清除被害木消灭虫源,以及幼虫期树干注射、成虫期喷洒化学农药等防治措施。     

白蜡窄吉丁幼虫及其天敌的种群空间生态位研究

【目的】为了明确白蜡窄吉丁Agrilus planipennis Fairmaire幼虫及其天敌在寄主树上的分布规律和相互关系。【方法】对天津和北京两个地区绒毛白蜡Fraxinus velutina和辽宁地区水曲柳F mandshurica上白蜡窄吉丁幼虫及其天敌的种群生态位进行研究。【结果】白蜡窄吉丁幼虫及其天敌的数量均随着寄主树干高度的增加而逐渐减少,但在不同寄主树种上的分布范围不同。绒毛白蜡上的分布范围较广,而在水曲柳主干上的分布高度相对较低。天敌对白蜡窄吉丁幼虫在空间资源的利用上也存在差异。在天津地区,白蜡吉丁柄腹茧蜂Spathius agrili Yang(膜翅目:茧蜂科)和啄木鸟(■形目:啄木鸟科)的跟随作用最强,且白蜡吉丁柄腹茧蜂与啄木鸟之间对空间资源的利用存在激烈竞争。在北京地区,啄木鸟的跟随作用最强,病原微生物、扁胫旋小蜂、白蜡吉丁柄腹茧蜂之间对空间和营养资源利用的竞争较激烈。而在辽宁地区,白蜡窄吉丁幼虫和天敌的分布范围较窄,各类天敌在空间上对寄主幼虫的跟随作用不是很明显,但不同天敌种类之间对空间和营养资源的利用也存在竞争。【结论】研究结果为白蜡窄吉丁的综合治理和天敌资源的保护利用提供了理论依据。     

New Coleoptera records from New Brunswick, Canada: Buprestidae

Nine species of Buprestidae; Agrilus bilineatus (Weber), Agrilus crinicornis Horn, Agrilus obsoletoguttatus Gory, Agrilus putillus putillus Say, Brachys ovatus (Weber), Buprestis sulcicollis (LeConte), Chalcophora liberta (Germar), Phaenops aeneola (Melsheimer), and Taphrocerus gracilis (Say) are newly recorded for New Brunswick, Canada. Agrilus bilineatus, A. crinicornis, A. obsoletoguttatus,and B. ovatus are also newly reported for the Maritime provinces. Lindgren 12-funnel traps do not appear to be an effective tool for sampling the Bupresidae. Collection, habitat notes, and distribution maps are presented for each species.     

The conserved mitochondrial genome of the jewel beetle (Coleoptera: Buprestidae) and its phylogenetic implications for the suborder Polyphaga

In this study, we sequenced the mitochondrial (mt) genome of Agrilus mali (Coleoptera: Buprestidae) using next-generation sequencing, and accordingly annotated 13 protein-coding, 22 tRNA, and 2 rRNA genes and a 1458-bp non-coding region. Comparative analysis indicated that the mt genome of A. mali is relatively conserved, with a typical gene content and order identical to those of other coleopterans. However, the newly sequenced mt genome is characterized by a relatively higher A + T content compared with that of other species within the family Buprestidae. Phylogenetic analysis based on Bayesian inference revealed that the evolutionary relationship among the six infraorders of the suborder Polyphaga is (Scirtiformia + (Elateriformia + ((Scarabaeiformia + Staphyliniformia) + (Bostrichiformia + (Cucujiformia))))). However, the topology indicated that the family Buprestidae is a sister group to other Polyphaga infraorders, excluding Scirtiformia as a monophyly, and thus the monophyly of Elateriformia was not supported. This study not only presents the mt genome of a species in the family Buprestidae and a comparative analysis of jewel beetles but also examines the contribution of mt genomes in elucidating phylogenetic relationships within the suborder Polyphaga of Coleoptera.     

Morphology, molecular characteristics and prevalence of a Cystosporogenes species (Microsporidia) isolated from Agrilus anxius (Coleoptera: Buprestidae)

A microsporidium was isolated from the bronze birch borer, Agrilus anxius Gory (Coleoptera: Buprestidae), collected near Sudbury and Sault Ste Marie, Canada. Light and electron microscopic investigations showed that gross pathology and ultrastructure of the investigated Cystosporogenes species was similar to those characterized and described for other Cystosporogenes species. Small subunit rRNA gene sequence data and comparative phylogenetic analysis confirmed that the microsporidian species from A. anxius is most closely related to the genus Cystosporogenes clade of microsporidia. Infection average in the Sudbury and Sault Ste Marie beetle populations was >80% and relatively stable in 2006-2007 but declined in 2008. Field prevalence of the A. anxius isolate, mechanisms that may potentially be involved in its horizontal (autoinfection) and vertical (transovarial) transmission, and disease dynamics are discussed. The congeneric relationship between Agrilus planipennis and A. anxius makes it imperative to study the virulence of this Cystosporogenes species in A. planipennis.     

Field observations of visual attraction of three European oak buprestid beetles toward conspecific and heterospecific models

Agrilus biguttatus Fabricius, Agrilus sulcicollis Lacordaire, and Agrilus angustulus Illiger (Coleoptera: Buprestidae) are three beetle species associated with oak trees [Quercus spp. (Fagaceae)] in Europe. In Hungary, all three species were observed in the foliage near freshly cut oak log piles. Agrilus biguttatus was active later in the afternoon, whereas the other species were observed earlier in the day. Dead female models of these three native Agrilus species, as well as the native species Agrilus cyanescens Ratzeburg and the non‐native Agrilus planipennis Fairmaire, were pinned onto adjacent leaves in direct sunlight to observe the visual mating approaches of the local male populations. Agrilus biguttatus and A. sulcicollis males flew toward and landed directly on the models from a distance of 1 m. Agrilus angustulus flew toward the models from a similar distance, but rather than landing directly on a model would alight on the leaf, 1–2 cm away, before walking closer to the model while antennating it. For all three species, there was substantial cross‐attraction to models of other species. Both A. biguttatus and A. sulcicollis males chose A. angustulus models less often than their respective conspecific models. Likewise, A. angustulus males approached A. sulcicollis models less often than their normal conspecific models. Agrilus biguttatus males attempted to copulate with both A. biguttatus and A. planipennis models, afterward remaining with them for several minutes. Agrilus biguttatus males spent more time on A. planipennis models than on conspecific models. Thus, there is substantial cross‐species attraction in visually mediated mating approaches and copulation behavior. These findings suggest a common behavioral template for visual mate‐finding among buprestids and a large degree of close‐range mating compatibility between A. biguttatus and A. planipennis.     

Trapping of European buprestid beetles in oak forests using visual and olfactory cues

Trapping approaches developed for the emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), were adapted for trapping several European oak buprestid species. These approaches included the use of natural leaf surfaces as well as green and purple plastic in sticky trap designs. Plastic surfaces were incorporated into novel ‘branch‐trap’ designs that each presented two 5 × 9‐cm² rectangular surfaces on a cardboard structure wrapped around the leaves of a branch. We used visual adult Agrilus decoys in an attempt to evoke male mating approaches toward the traps. Our first experiment compared the attractiveness of visual characteristics of the surfaces of branch‐traps. The second looked at the effect on trap captures of adding semiochemical lures, including manuka oil, (Z)‐3‐hexen‐1‐ol, and (Z)‐9‐tricosene. In total, 1 962 buprestid specimens including 14 species from the genus Agrilus were caught on 178 traps in a 22‐day time‐span. Overall, the green plastic‐covered branch‐traps significantly out‐performed the other trap designs. We further found that the presence of an EAB visual decoy placed on the trap surface often increased captures on these green traps, but this effect was stronger for certain Agrilus species than for others. The visual decoy was particularly important for the most serious pest detected, Agrilus biguttatus Fabricius, which was captured 13 times on traps with decoys, but only once without a decoy. There were some small but significant effects of odor treatment on the capture of buprestids of two common species, Agrilus angustulus Illiger and Agrilus sulcicollis Lacordaire. There were also 141 Elateridae specimens on these traps, which were not influenced by trap type or decoys. The results suggest that small branch‐traps of this nature can provide a useful new tool for monitoring of buprestids, which have the potential to be further optimized with respect to visual and olfactory cues.     

Developing a non-sticky trap design for monitoring jewel beetles

There is an urgent need in Europe to prepare resources for the arrival of the emerald ash borer, Agrilus planipennis (Buprestidae, Coleoptera) from European Russia, and possibly other invasive jewel beetles. A lightweight, easy to handle, non-sticky trap could facilitate monitoring and detection to derive information about emerald ash borer and other jewel beetle populations. In two experiments carried out over two consecutive years in an oak forest, a new non-sticky multi-funnel trap design with a light-green (sometimes described as fluorescent yellow) visual cue was developed. Altogether, there were 238 (2018) and 194 (2019) specimens captured often (2018) and eight (2019) Agrilus species, eight of which are oak-related and one (A. convexicollis) was linked to ash. The new light-green multi-funnel trap performed similarly to the sticky design with a similar coloured surface. Our results suggest that the new trap design may be suitable for catching a wide range of buprestid species. It may also have the potential to be further optimized with respect to visual and olfactory cues, which would provide an even more useful tool for monitoring both invasive and indigenous buprestids.     

Novel visual-cue-based sticky traps for monitoring of emerald ash borers, Agrilus planipennis (Col., Buprestidae)

We examined various methods of trapping emerald ash borers (EAB), Agrilus planipennis Fairmaire, using solely visual cues based on previous work that has documented the importance of visual cues in EAB mate location. Here, we give the results of two of these methods, coloured sticky cards (yellow or blue), or live ash leaves covered with spray-on adhesive to which dead male EAB visual lures had been pinned. Feral male beetles were captured effectively on the sticky traps made from dead male EAB on ash leaves. These sticky-leaf-traps captured more male EAB when deployed in high-population density areas than low-density areas, but did capture EAB even at lower population densities. More feral males were captured on these traps when they were placed higher in the trees, regardless of the population density of EAB. Very few feral female EAB were captured using the sticky-leaf-traps. This novel method of EAB trapping may allow 'real-time' population detection and monitoring of EAB adults during the active flight period rather than locating larval galleries during the autumn and winter after adult flight and attack. Feral male beetles were also captured using standard yellow- or blue-coloured sticky cards to which male EAB had been affixed with adhesive; however, this type of trap was much less effective overall than using the sticky-leaf-traps. Furthermore, Agrilus cyanescens , a species similar in colour to EAB but smaller in size, showed a strong response to blue-coloured sticky traps to which dead male EAB had been affixed with adhesive, suggesting a general use of visual cues in the mating systems of some of the other Buprestidae as well.     

Agrilus mali Matsumara (Coleoptera: Buprestidae), a new invasive pest of wild apple in western China: DNA barcoding and life cycle

Agrilus mali Matsumara (Coleoptera: Buprestidae) is a wood‐boring beetle distributed to eastern China that occasionally injures apple species. However, this wood‐boring beetle is new to the wild apple forests (Malus sieversii) of the Tianshan Mountains (western China) and has caused extensive tree mortality. The development of a biological control program for these wild apple forests is a high priority that requires exploration of the life cycle, DNA barcoding and taxonomic status of A. mali. In this study, to determine the diversity of invasive beetles, a fragment of the mitochondrial cytochrome oxidase gene was analyzed. Based on the results, beetles from Gongliu and Xinyuan counties of Xinjiang were identical but differed from those in the apple nursery of Gongliu by a single‐nucleotide substitution. We summarize the taxonomic status, relationships, and genetic distances of A. mali among other Agrilus species using the Tajima‐Nei model in maximum likelihood phylogeny. Analysis revealed that A. mali was closely related to Agrilus mendax and both belong to the Sinuatiagrulus subgenus. The life cycle of A. mali was investigated based on a monthly regular inspection in the wild apple forests of Tianshan. Similar to congeneric species, hosts are injured by larvae of A. mali feeding on phloem tissue, resulting in serpentine galleries constructed between bark and xylem that prevent nutrient transport and leading to tree mortality. Future studies will focus on plant physiological responses to the invasive beetles and include surveys of natural enemies for a potential classical biological control program.     

中国白蜡窄吉丁研究进展

白蜡窄吉丁Agrilus planipennis Fairmaire是近年来发生和影响比较严重的国际性检疫害虫,主要危害白蜡属(Fraxinus spp.)树木。它以幼虫在树木的韧皮部、形成层和木质部浅层蛀食,从而切断树木的营养输导组织,导致树木衰弱死亡。为了深入了解该害虫,探索合理的治理策略,本文对国内外有关白蜡窄吉丁的生物学特性,包括生活习性、生活史、分布与危害、寄主范围等方面以及防治技术的研究进展进行了系统总结,并讨论了白蜡窄吉丁今后的研究方向和研究趋势。     

Can the destruction of California’s oak woodlands be prevented? Potential for biological control of the goldspotted oak borer, <Emphasis Type="Italic">Agrilus auroguttatus</Emphasis>

The goldspotted oak borer (GSOB), Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), is an introduced and aggressive phloem/wood borer infesting native oaks in southern California. Elevated levels of oak mortality have occurred continually for the last nine years on three oak species in San Diego Co., California, USA. Biological control is being assessed as an option for long-term and widespread management of the invasive population of GSOB. Foreign exploration in the native ranges of GSOB and a related sibling species (Agrilus coxalis Waterhouse) was conducted to determine life history information, to assess the natural enemy complex, and to collect specimens for molecular analyses that could help to identify the area of origin of California’s introduced population. Two species of parasitoids, Calosota elongata Gibson (Eupelmidae) and Atanycolus simplex Cresson (Braconidae), were discovered with GSOB populations in Arizona and California. No insect natural enemies were found with populations of A. coxalis in southern Mexico. However, Quercus conzatti Trel. and Quercus peduncularis Nee in Oaxaca and Chiapas, respectively, were recorded as the first known hosts of A. coxalis. A comparative analysis of our understanding of the natural enemy complexes for other pestiferous Agrilus with that of GSOB suggests that more effort should be directed at uncovering potential egg parasitoids and microbial pathogens of GSOB. Analyses of mitochondrial and nuclear ribosomal DNA (rDNA) revealed that the California population of GSOB was more similar to the Arizona population. Specimens of A. coxalis from southern Mexico were confirmed as a separate species. Additional surveys and sampling are needed across the complete native range of the GSOB species complex to develop a comprehensive inventory of parasitoid species that could be considered for use in a classical biological control program in California and to delineate the area of origin of California’s population.