Department of Forensic Medicine, Soochow University, Suzhou, China.
Criminal Police Branch, Yancheng Public Security Bureau, Yancheng, China.
J Med Entomol. 2019 Sep 3;56(5):1215-1224. doi: 10.1093/jme/tjz052.
The age of insects found on corpses is often used to estimate the minimum postmortem interval by forensic entomologists. Insect development is affected by biotic and abiotic factors, and temperature is the most important environmental factor that determines the length of insect development. Chrysomya rufifacies (Macquart) (Diptera: Calliphoridae) is a globally distributed fly that is commonly found on corpses, and this study investigated the development of C. rufifacies from China at various constant temperatures. At 16, 19, 22, 25, 28, 31, and 34°C, the developmental time from egg to adult was 870.17 ± 11.50, 566.20 ± 8.79, 406.38 ± 10.98, 291.14 ± 4.71, 232.59 ± 5.96, 192.47 ± 3.45, and 160.48 ± 7.15 h, respectively. We established three developmental models for C. rufifacies to estimate the age of the developing insect: the isomorphen diagram model, the isomegalen diagram model and the thermal summation model. Regression analysis was conducted to obtain the relationship between body length and development time of the larvae from hatching to wandering. The developmental threshold temperatures of the egg, 1st instar, 2nd instar, 3rd instar, and wandering larvae, and intra-puparial stages were 12.28 ± 0.30, 11.74 ± 0.95, 12.70 ± 0.55, 11.68 ± 0.96, 10.53 ± 1.53, and 12.51 ± 0.41°C, respectively. The developmental threshold temperature, and the thermal summation constant during the entire developmental period were 3759.95 ± 170.80 degree hours and 11.96 ± 0.38°C, respectively. This study provides an improved dataset to estimate the postmortem interval of corpses using C. rufifacies.
法医昆虫学家常通过研究尸体上的昆虫年代来估算最小死后间隔时间。昆虫的发育受到生物和非生物因素的影响，而温度是决定昆虫发育时长的最重要环境因素。红头丽蝇（Chrysomya rufifacies）（双翅目：丽蝇科）是一种分布广泛的蝇类，通常在尸体上发现，本研究调查了来自中国的红头丽蝇在不同恒温下的发育情况。在 16、19、22、25、28、31 和 34°C 下，从卵到成虫的发育时间分别为 870.17 ± 11.50、566.20 ± 8.79、406.38 ± 10.98、291.14 ± 4.71、232.59 ± 5.96、192.47 ± 3.45 和 160.48 ± 7.15 h。我们建立了三个红头丽蝇的发育模型来估计发育中昆虫的年龄：等角形图模型、等角形图模型和热积累模型。进行回归分析以获得从孵化到游动幼虫的体长与发育时间的关系。卵、1 龄幼虫、2 龄幼虫、3 龄幼虫和游走幼虫及蛹内各阶段的发育起始温度分别为 12.28 ± 0.30、11.74 ± 0.95、12.70 ± 0.55、11.68 ± 0.96、10.53 ± 1.53 和 12.51 ± 0.41°C。整个发育期的发育起始温度和热积累常数分别为 3759.95 ± 170.80 度小时和 11.96 ± 0.38°C。本研究提供了一个改进的数据集，可使用红头丽蝇来估计尸体的死后间隔时间。
