Hans Krystal R, Vanlaerhoven Sherah L
Department of Biology, University of Windsor, 401 Sunset Ave, Windsor, ON N9B 3P4, Canada.
Department of Entomology, Purdue University, 901 W. State St., West Lafayette, IN 47907, USA.
Insects. 2021 Mar 25;12(4):280. doi: 10.3390/insects12040280.
Estimates of the minimum post-mortem interval (mPMI) using the development rate of blow flies (Diptera: Calliphoridae) are common in modern forensic entomology casework. These estimates are based on single species developing in the absence of heterospecific interactions. Yet, in real-world situations, it is not uncommon to have 2 or more blow fly species developing on a body. Species interactions have the potential to change the acceptance of resources as suitable for oviposition, the timing of oviposition, growth rate, size and development time of immature stages, as well as impacting the survival of immature stages to reach adult. This study measured larval development and growth rate of the blow flies (Meigen, 1826), (Meigen, 1826) and Robineau-Desvoidy (Diptera: Calliphoridae) over five constant temperatures (15, 20, 25, 30, 35 °C), in the presence of conspecifics or two-species heterospecific assemblages. Temperature and species treatment interacted such that larvae gained mass more rapidly when in the presence of at 20 and 30 °C, however only developed faster at first instar. At later stages, the presence of slowed development of immatures. Development time of immatures was not affected by the presence of , however larvae gained mass more slowly. Development time of immatures was faster in the presence of either or until third instar, at which point, the presence of was neutral whereas negatively impacted development time. larvae gained mass more rapidly in the presence of at 20 °C but were negatively impacted at 25 °C by the presence of either or . The results of this study indicate that metrics such as development time or larval mass used for estimating mPMI with blow flies are impacted by the presence of comingled heterospecific blow fly assemblages. As the effects of heterospecific assemblages are not uniformly positive or negative between stages, temperatures or species combinations, more research into these effects is vital. Until then, caution should be used when estimating mPMI in cases with multiple blow fly species interacting on a body.
利用丽蝇（双翅目：丽蝇科）的发育速率来估计最短死后间隔时间（mPMI）在现代法医昆虫学案件工作中很常见。这些估计是基于单一物种在没有异种相互作用的情况下的发育情况。然而，在现实世界中，一具尸体上出现两种或更多种丽蝇发育的情况并不罕见。物种间的相互作用有可能改变对适合产卵资源的接受程度、产卵时间、生长速率、未成熟阶段的大小和发育时间，以及影响未成熟阶段存活至成虫的情况。本研究在五个恒定温度（15、20、25、30、35℃）下，在同种或两种异种组合存在的情况下，测量了丝光绿蝇（Meigen，1826）、红头丽蝇（Meigen，1826）和棕尾别麻蝇Robineau-Desvoidy（双翅目：丽蝇科）幼虫的发育和生长速率。温度和物种处理存在相互作用，使得丝光绿蝇幼虫在20℃和30℃下与红头丽蝇共存时体重增加更快，但仅在一龄时发育更快。在后期阶段，红头丽蝇的存在减缓了丝光绿蝇未成熟阶段的发育。棕尾别麻蝇未成熟阶段的发育时间不受红头丽蝇存在的影响，然而幼虫体重增加更慢。棕尾别麻蝇未成熟阶段在与丝光绿蝇或红头丽蝇共存时发育更快，直到三龄，此时，丝光绿蝇的存在是中性的，而红头丽蝇则对发育时间有负面影响。丝光绿蝇幼虫在20℃下与棕尾别麻蝇共存时体重增加更快，但在25℃下，棕尾别麻蝇或红头丽蝇的存在对其有负面影响。本研究结果表明，用于估计丽蝇mPMI的发育时间或幼虫体重等指标会受到混合异种丽蝇组合存在的影响。由于异种组合的影响在不同阶段、温度或物种组合之间并非一致的积极或消极，因此对这些影响进行更多研究至关重要。在此之前，在估计有多种丽蝇在尸体上相互作用的案件中的mPMI时应谨慎。
