Tracking Global Invasion Pathways of the Spongy Moth (Lepidoptera: Erebidae) to the U.S. using Stable Isotopes as Endogenous Biomarkers

MEASUREMENTSThe data was obtained at the University of Natural Resources and Life Sciences isotope laboratory (Tulln, Austria) between 2017 and 2019 by analysing tissue of spongy moths (Lymantira dispar, Lepidoptera: Erebidae, formally known as "gypsy moth") for their hydrogen stable isotope ratio (2H/1H = δ2H) using a TC/EA system (Thermo Fisher), a ConFlo III open split interface (Thermo Fisher) and a DeltaPLUS XP isotope-ratio mass spectrometer (IRMS, Thermo Fisher) nitrogen stable isotope ratio (15N/14N = δ15N) using a EA (Flash 2000) and IRMS Delta V system (Thermo Fisher) For δ2Hanalysis, quadruplet samples of 0.2±0.025 mg each of the moths’ tarsus (lowest part of the leg, dominantly consisting of chitin) were weighed into silver capsules for solids (3.3x5 mm, IVA Analysentechnik). Eggs were sampled as a whole. A full complement of in-house water reference materials (measured against VSMOW and VSLAP) and the international standards IAEA CH7 PEF1 (δ2H = -100.3‰), USGS 43 Indian hair (δ2H = -44.4‰), IVA Casein 139443 (δ2H = -113.0‰) and IVA NBS22 (δ2H = -116.9‰) were used. The H3+ contribution (“H3-factor”) was determined before every measurement. For the δ15N analysis, 2±0.3 mg of moth tissue were sampled into tin capsules for solids (5x8 mm, IVA Analysentechnik). Due to a lack of samples, multiple specimens were combined into one sample for the δ15N analysis. This introduced additional variance to the δ15N results. We used IVA Urea (δ15N = -0.36‰), IAEA 600 Caffeine (δ15N = 0.9‰) and IVA Casein 165389 (δ15N = 5.9‰) as reference materials.

测量详情
本数据集于2017至2019年间，在奥地利图尔恩的自然资源与生命科学大学同位素实验室获取，通过分析舞毒蛾（Lymantira dispar，鳞翅目：裳蛾科，原正式名称为“吉普赛蛾”）的组织样本，分别测定其氢稳定同位素比（2H/1H = δ2H）与氮稳定同位素比（15N/14N = δ15N）。其中氢稳定同位素比分析采用TC/EA系统（赛默飞世尔科技，Thermo Fisher）、ConFlo III开放式分流接口（赛默飞世尔科技）以及DeltaPLUS XP同位素比值质谱仪（Isotope-Ratio Mass Spectrometer，简称IRMS）；氮稳定同位素比分析则使用元素分析仪（EA，Elemental Analyzer，Flash 2000）与IRMS Delta V系统（赛默飞世尔科技）完成。
针对氢稳定同位素（δ2H）分析：称取0.2±0.025 mg的舞毒蛾跗节（腿部最末端结构，主要由几丁质构成）四份平行样品，装入固体样品专用银坩埚（规格3.3×5 mm，IVA Analysentechnik品牌）中。卵样本则采用整枚取样的方式。本次分析使用了全套实验室内部水标准物质（以维也纳标准平均海水（Vienna Standard Mean Ocean Water，VSMOW）与维也纳标准南极轻降水（Vienna Standard Light Antarctic Precipitation，VSLAP）为校准基准），以及国际标准物质IAEA CH7 PEF1（δ2H = -100.3‰）、USGS 43印度毛发（δ2H = -44.4‰）、IVA Casein 139443（δ2H = -113.0‰）与IVA NBS22（δ2H = -116.9‰）。每次测量前均需测定H3+离子贡献量（即“H3因子”）。
针对氮稳定同位素（δ15N）分析：称取2±0.3 mg的蛾类组织，装入固体样品专用锡坩埚（规格5×8 mm，IVA Analysentechnik品牌）中。由于样本量不足，本次氮同位素分析采用多份标本合并为单一样本的方式，该操作会为δ15N结果引入额外的方差。本次分析使用的标准物质包括IVA尿素（δ15N = -0.36‰）、IAEA 600咖啡因（δ15N = 0.9‰）与IVA Casein 165389（δ15N = 5.9‰）。