温度对4种常见尸食性蝇类生长发育的影响及其法医学意义

为查明温度对尸食性蝇类生长发育的影响，便于推断死亡时间，在实验室恒温条件下，以常见的4种尸食性蝇类，即巨尾阿丽蝇Aldrichinagrahami、丝光鲜蝇Luciliasericata、大头金蝇Chrysomyamegacephala和肥须亚麻蝇Parasarcophagacrassipalpis为材料进行研究。结果表明，在实验温度范围内，除巨尾阿丽蝇二、三龄幼虫和丝光绿蝇三龄幼虫之外，各种类各发育阶段的历期均随温度增高而缩短，巨尾阿丽蝇蛹在12℃和30℃时停止发育。根据试验结果，利用线性回归方程对发育速率与温度间的关系进行了模拟，结果均有良好的相关性。研究结果具有推断死亡时间的法医学意义。     

四种常见尸食性蝇类活动与产卵习性

目的：明确常见尸食性昆虫成虫的活动习性和产卵习性,为法医实践中死后间隔时间的判断提供借鉴;方法：在自然温度、室内恒温及包括夜晚、雨天等26种不同环境条件对丝光绿蝇、大头金蝇、巨尾阿利蝇、棕尾别麻蝇成虫活动与产卵（产仔）习性进行了观察;结果：昆虫成虫的活动与产卵习性在不同环境条件下往往不同,不同种类之间也存在差异,在利用昆虫发生规律为法医实践提供死亡时间等信息时,应具体问题具体分析。     

成都市嗜尸昆虫种类季节变化研究

目的 研究成都市嗜尸昆虫种类及其与季节变化的关系。方法 经过两年重复试验,观察3～11月兔尸上嗜尸昆虫种类变化。结果 发现3～11月兔尸上出现的嗜尸昆虫种类主要有舍蝇、丝光绿蝇、大头金蝇、赭尾麻蝇、巨阿尾丽蝇。其中,巨阿尾丽蝇见于3、4月,舍蝇出现于4月中旬至10月初,而大头金蝇、丝光绿蝇、赭尾麻蝇则自3月至10月中下旬均可见到,10月底以后则见不到任何嗜尸苍蝇。幼虫的出现晚于成虫1～4天不等,与季节及环境有关。结论 通过舍蝇、丝光绿蝇、大头金蝇、赭尾麻绳、巨阿尾丽蝇的生命周期的研究,有望为成都市法医学实践中死亡时间的推断提供依据。     

四种常见尸食性蝇类活动与产卵习性

目的　明确常见尸食性昆虫成虫的活动习性和产卵习性 ,为法医实践中死后间隔时间的判断提供借鉴 ;　方法　在自然温度、室内恒温及包括夜晚、雨天等 2 6种不同环境条件对丝光绿蝇、大头金蝇、巨尾阿利蝇、棕尾别麻蝇成虫活动与产卵 (产仔 )习性进行了观察 ;　结果　昆虫成虫的活动与产卵习性在不同环境条件下往往不同 ,不同种类之间也存在差异 ,在利用昆虫发生规律为法医实践提供死亡时间等信息时 ,应具体问题具体分析。     

北京地区尸生性蝇类研究及其在法医鉴定中的应用

为提供法医学尸体死亡时间鉴定的准确性，对北京地区人尸上蝇类区系进行了系统调查（1994～1996）。发现本地区共有双翅目尸生性蝇类3科、12属、14种。其中常见种有红头丽蝇、丝光绿蝇、大头金蝇、肥须亚麻蝇、急钓亚麻蝇、棕尾别麻蝇和家蝇7种。对其常见种的幼虫进行不同温度和湿度下培养，观察常见环境因素，如日历期、风雨天气等因素对其生长发育速率的影响。结果表明，蝇类幼虫在其适宜生长发育的温度范围内，随着温度的升高发育速率加快，历期缩短；在同一温度和同一饲养条件下，发育速率因种而异；平均温度在28℃左右时，蝇类幼虫发育最快，尤其是1～2龄幼虫，时间为1天左右，且较稳定。这些数据对法医学推断死亡时间具有参考价值。     

利用积温和昆虫发育历期推测死亡时间的研究

目的积累尸食性蝇类虫态发育历期和积温的资料。方法采用动物尸体作诱饵,分别对自然飞到诱饵上繁殖生长的6种尸食性蝇类的虫态发育历期和积温进行观察研究。结果经过观察,取得了棕尾别麻蝇、丝光绿蝇、紫绿蝇、宽丽蝇、巨尾阿丽蝇、大头金蝇等6种尸食性蝇类的虫态发育历期和积温的基础数据。并采用倒计积温的方法推测实际案例中死者死亡时间,破案后证实推测时间与实际死亡时间一致。结论本文数据可为利用尸食性蝇类虫态育历期的积温推测死亡时间提供依据。     

温度对丝光绿蝇幼虫发育速度影响

丝光绿蝇（Luciliasericata），属丽蝇科，俗称绿豆蝇，是一种分布极广的冈食性蝇类，主要李生在腐败动物质中，是尸体腐败过程中最常见的蝇种[1]。其生活史中经历有蝇（成虫）→卵十幼虫（蛆）→蛹→蝇的过程。根据尸体上该蝇种生活史的不同阶段特点，可以推断尸体的死亡时间。目前国外已有在实验室条件下观察记录蝇类生活史为主的基础研究报告[2，5]，但在国内尚未见有关报道。本文选择尸体腐败过程中最常见的丝光绿蝇为对象，研究其在8种实验恒温条件下生长发育速度．并取得基础数据，现报告如下。材料和方法将家兔处死后，放置于室外让…     

深圳地区大头金蝇年生长发育规律观察

目的观察深圳地区优势嗜尸性蝇种大头金蝇在尸体腐败分解过程中的发育历变化规律,并探讨其用于死亡时间推断的可能性。方法在调查深圳地区嗜尸性昆虫物种谱系的基础上,设置自然环境下的家猪尸体腐败模型,观察记录大头金蝇到达尸体、蝇蛆出现、大量出现、开始离食、大量离食、开始化蛹、大量化蛹,蛹开始羽化和大量羽化9个发育历期关键时间点。同时,收集处理成虫和幼虫,测量体长并模拟二元方程用于死亡时间推断。结果深圳地区不同季节中,大头金蝇在尸体上的生长发育具有规律性,蛆虫的离食时间点和羽化时间点对应的腐败分期在各个季节基本相同,前者基本处于腐败期,后者处于后腐败期。该地区四季蝇蛆长随死亡时间的变化模拟成二项式方程,分别为春季:y=-0.000 2x2+0.147 5x-0.925(R2=0.989 3);夏季:y=-0.001 4x2+0.316 6x-4.499 8(R2=0.970 1);秋季:y=-0.000 4x2+0.187 8x-1.107 9(R2=0.987 8);冬季:y=0.000 4x2-0.080 3x+4.367(R2=0.994 9)。结论大头金蝇在尸体上发育历期有一定的规律性,特别是蛆虫的离食时间点和羽化时间点对死亡时间推断的参考价值。     

贵阳市郊嗜尸蝇类群落组成及生长观察

目的观察嗜尸蝇类种群落组成、季节变动及蛆虫生长长度与死亡时间的关系，为在死亡时间推断中应用提供基础数据。方法采用荷兰猪尸／兔尸／猪肺作诱饵，在海拔1115．2～1120．8m的自然环境中吸引蝇种。捕抓特定时间段内优势蝇种，每日定时观察记录其在营养基上产卵、幼虫孵化、成熟幼虫爬离的时间，测量其长度，采用Excel软件进行数据处理。结果获取了贵阳市郊宽丽蝇、巨尾阿丽蝇、紫绿蝇、丝光绿蝇、棕尾别麻蝇、肥躯金蝇、大头金蝇和绯颜裸金蝇等8种常见嗜尸蝇类群落组成、季节变动及蛆虫生长长度的规律性变化数据，并用于实际案例死亡时问的推断。结论嗜尸蝇类群落组成、季节变动及蛆虫生长长度在推测死亡时间上有重要意义。     

新乡地区夏季常见嗜尸性昆虫群落演替规律初步研究

目的研究新乡地区夏季嗜尸性昆虫的种类及其群落演替规律。方法观察法研究新乡医学院动物房后偏僻草地上6只大白鼠和5只家兔尸体腐败过程中嗜尸性蝇类的主要物种及其群落演替规律。结果该地区主要出现嗜尸性蝇类为双翅目3科7种,包括家蝇、大头金蝇、丝光绿蝇、棕尾别麻蝇、黑尾黑麻蝇、厩腐蝇、元厕蝇,且呈现出演替规律性。结论研究结果可作为新乡地区对尸体死亡时间的推断依据。     

Molecular Identification of Necrophagous Dermestes Species in South Korea Using Cytochrome c Oxidase Subunit I Nucleotide Sequences (Genus Dermestes)

Species identification of necrophagous insects found on a dead body is an essential key in applying medicolegal entomology to the estimation of postmortem interval (PMI). Due to limited morphological identification of insect evidence, several studies have identified species using molecular information such as DNA markers. While considerable cytochrome c oxidase subunit I (COI) gene sequence data of necrophagous fly species have been collected and annotated, those of necrophagous beetle species have not. Since necrophagous beetles such as Dermestes species have a larval period longer than that of flies, beetles are useful in even the late decomposition phase in estimating minimum PMI. To obtain the full-length COI gene sequences of six Dermestes species collected from South Korea, we designed primers for polymerase chain reaction amplification and sequencing. The obtained full COI nucleotide sequences were used for performing phylogenic analysis and comparison with previously reported sequences. The results demonstrated that the COI gene sequences could be used to identify forensically important Dermestes species in South Korea.     

青岛地区常见嗜尸性蝇种及其季节性分布研究

目的观察青岛地区嗜尸性蝇种季节性演替规律,为死亡时间推断提供参考。方法在室外设立田间观察场所,2012年4月1日开始至2013年4月1日,每月第1天6时放置猪尸,20min后开始观察,至18时,期间每小时观察1次;第3天以后,分别于7时、12时、18时各观察1次。观察时记录尸体上出现的昆虫种类、虫态、数量并采集相应标本,进行分类鉴定。结果可以观察到有嗜尸性蝇类侵袭尸体的月份为4月至11月,共发现3科23种蝇类,其中丝光绿蝇、大头金蝇和亮绿蝇数量位列前三,分别占全部观察数量的40.71%、31.95%和7.12%。丝光绿蝇、大头金蝇中午时段出现的数量显著多于早上和傍晚。一年中各种蝇类在中午出现的数量均多于早上及晚上。4月上旬,蝇类早、晚与中午出现的数量相差显著;而在7、8月份差别较小。大部分嗜尸性蝇种集中在新鲜期和肿胀期。结论本文观察数据可为利用嗜尸性蝇类演替规律进行法医学死亡时间推断,以及建立地区嗜尸性蝇种类数据提供参考。     

Postmortem interval (PMI) determined by study sarcophagous biocenoses: three cases from the province of Venice (Italy).

This paper presents and discusses three cases of cadavers found, unburied, in the province of Venice, Northern Italy. In each case, all insect species playing some role in carrion decay processes, both sarcophagous and their predators, found on or in the bodies, were collected and determined. In one case, many larvae of the black soldier fly, Hermetia illucens L. (Diptera: Stratiomyidae) were found and are reported, for the first time in Italy, as necrophagous. Experimental breeding of some fly species was also carried out in controlled temperature and humidity conditions. In particular, it was of interest to know how the Neotropical black soldier fly modified its life-cycle to adapt to a temperate climate. It was thus possible to establish the rate of larval growth and timing of pupation, emergence, oviposition and hatching in various external conditions. The postmortem interval (PMI) established by identifying the life-cycle stages of dipterofauna were later confirmed in all cases through police investigations and the results of forensic analyses.     

Debugging Decomposition Data—Comparative Taphonomic Studies and the Influence of Insects and Carcass Size on Decomposition Rate

Abstract:  Comparison of data from a variety of environments and ambient temperatures has previously been difficult as few studies used standardized measures of time/temperature and decomposition. In this paper, data from previous studies and recent experiments are compared using simple conversions. These conversions allow comparison across multiple environments and experiments for the first time. Plotting decomposition score against logADD allows the exponential progression of decomposition to be expressed as a simple linear equation. Data comparison from many environments and temperatures shows no difference in decomposition progression when measured using Accumulated Degree Days. The major effector of change in rate was insect presence, regardless of depositional environment, species, or season. Body size is significant when carcasses are accessed by insects; when insects are excluded, while bodies are indoors, submerged, or buried, then decomposition progresses at the same rate regardless of body size.     

Bionomics of two forensically important blowfly species Chrysomya megacephala and Chrysomya putoria (Diptera: Calliphoridae) reared on four types of diet

The use of heterogeneous animal tissues for the rearing of necrophagous insect species can produce uneven biological data, which can compromise the determination of larval age and, consequently, estimates for post-mortem intervals. We investigated the development of two species, Chrysomya megacephala and Chrysomya putoria (Diptera: Calliphoridae), reared on four substrates: minced beef (control) and semi-synthetic diets with the addition of sardine, rumen or chicken eggs. No differences in total developmental times were detected among larvae reared on different diets. Length and width of larvae were partially affected by the type of food. Third instar larvae and pupae of both species were heavier on beef treatment when compared with other substrates. Overall mortality was lower when beef was used as food. Longevity of adults and sex ratio were not negatively affected by the use of diets. Egg-based diet was the least effective for both species. Given the fact that several bionomical parameters of larvae reared on diets were close to those obtained when minced beef was offered, and considering the putrid odour, frequency of contamination and lack of homogeneity of animal tissue, semi-synthetic diets can be used for rearing C. megacephala and C. putoria.     

四季尸食性蝇类参与尸体软组织分解过程初探

目的观察了解四季尸食性蝇类参与尸体软组织分解过程的规律。方法在室外自然环境中设置尸体,分别在春、夏、秋、冬季节,用肉眼观察尸体每一时段的变化及尸食性蝇类参与尸体分解的现象。结果在4个不同的季节中,尸体软组织分解过程中尸食性蝇类参与种类及虫态各不相同。通过观察获得尸体变化各阶段的大体历期,尸体变化各阶段常见的尸食性蝇种及虫态资料。结论观察所得资料可为推测晚期尸体的死亡时间提供参考。     

mtDNA COI和ND5基因用于鉴别常见嗜尸性蝇类

目的对蝇类mtDNA 523bp COI和347bp ND5基因片段进行序列分析,评价其在以嗜尸性蝇类种属鉴定中应用的可行性。方法从广州(广东省)、湛江(广东省)、韶关(广东省)、沈丘(河南省)及蜂蛹寨(四川省)采集7种嗜尸性蝇类标本,进行形态学种属鉴定,取其腹部肌肉提取DNA,利用基因特异性引物对线粒体COI、ND5基因进行PCR扩增,产物经纯化后进行测序,MEGA 3.0软件对DNA序列进行碱基组成、进化分歧率和系统发育分析。结果进化分歧率ND5基因种内小于1.83%,种间大于2.62%;种间与种内进化分歧率范围间没有交叉;COI基因种间在0.48%～14.8%之间,种内在0.24%～8.3%之间,种内进化分歧范围与种间进化分歧范围存在交叉。结论 ND5基因片段可在种水平有效鉴别常见嗜尸性蝇类,也可鉴别近缘种。而单独运用COI基因不能有效进行种属鉴定。     

Practice of forensic entomology--usability of insect fragments in the estimation of the time of death

Forensic entomology analyzes and evaluates the presence of necrophagous or necrophilic insects on human corpses to estimate the post-mortem interval. The three cases presented are good examples illustrating that not only the various stages of development of the necrophagous insects from egg via larva to pupa are useful for forensic assessment. Depending on the situation in the individual case, even inconspicuous remains of past insect activity such as empty pupal cases or larval skins may supply important entomological information. For this purpose it is indispensable to preserve such evidence, which may appear only as fragments or pieces at first sight, for proper entomological assessment.