First Record of the Hairy Maggot Blow fly, Chrysomya rufifacies (Diptera: Calliphoridae) in Indiana

The hairy maggot blow fly, Chrysomya rufifacies (Macquart) is native to Australia but has been spreading to a worldwide distribution and is becoming established in the United States. This paper presents the first documentation of the species in Indiana, specifically Valparaiso, Indiana. The species was found in September 2017 and again in October 2019. Its presence is variable in Northwest Indiana, but seems to be found in the fall when the temperatures are at least 30°C prior to collection

Diurnal Oviposition of Blow Flies in Different Aged Carrion

Blow flies (Diptera: Calliphoridae) are among the first insects to oviposit (lay eggs) on carrion. The timing of blow fly oviposition is critical for determining a postmortem interval (PMI) estimation, which is the time that has passed between death and corpse discovery. The objective of this investigation is to gain more information about the timing of blow fly oviposition in relation to sunrise. Past research in our lab has shown that blow fly oviposition occurs an average of 4.75 hours after sunrise. This year’s research expanded on previous studies by placing six piglets of different ages, in a remote, wooded area one hour after sunrise. To see if there was a difference in the timing of oviposition related to the age of the carrion, three of the piglets had been thawed for 15 hours (new pigs), and the other three had been thawed for approximately 55 hours (old pigs). The piglets were checked once an hour until oviposition occurred, and it was recorded whether flies and eggs were present each hour. Egg masses were collected and reared to the third larval instar stage for identification using taxonomic keys. The timing of oviposition, in hours after sunrise, was compared between treatments and there was no significant difference found (P=.441). The research was repeated five times in the fall of 2017. The most common flies found ovipositing were Diptera: Calliphoridae, Phormia regina (Meigen) and Diptera: Calliphoridae, Lucilia coeruleiviridis (Macquart). This research has importance in both the scientific and forensic communities, as a more accurate PMI can strengthen the validity of a forensic investigation

Diurnal Oviposition of Blow Flies in Different Aged Carrion

Blow flies (Diptera: Calliphoridae) are among the first insects to oviposit (lay eggs) on carrion. The timing of blow fly oviposition is critical for determining a postmortem interval (PMI) estimation, which is the time that has passed between death and corpse discovery. The objective of this investigation is to gain more information about the timing of blow fly oviposition in relation to sunrise. Past research in our lab has shown that blow fly oviposition occurs an average of 4.75 hours after sunrise. This year’s research expanded on previous studies by placing six piglets of different ages, in a remote, wooded area one hour after sunrise. To see if there was a difference in the timing of oviposition related to the age of the carrion, three of the piglets had been thawed for 15 hours (new pigs), and the other three had been thawed for approximately 55 hours (old pigs). The piglets were checked once an hour until oviposition occurred, and it was recorded whether flies and eggs were present each hour. Egg masses were collected and reared to the third larval instar stage for identification using taxonomic keys. The timing of oviposition, in hours after sunrise, was compared between treatments and there was no significant difference found (P=.441). The research was repeated five times in the fall of 2017. The most common flies found ovipositing were Diptera: Calliphoridae, Phormia regina (Meigen) and Diptera: Calliphoridae, Lucilia coeruleiviridis (Macquart). This research has importance in both the scientific and forensic communities, as a more accurate PMI can strengthen the validity of a forensic investigation

Death Stinks: Characterizing the Volatiles that Attract Blow Flies During Decomposition

Blow flies (Diptera: Calliphoridae) are attracted to the volatile compounds (organic compounds that easily become airborne) given off by decomposing matter. Baits are often used as human substitutes in forensic entomology, and a bait should approximate the volatiles given off by decomposing human bodies as closely as possible. This fact has led us to investigate the different volatiles, and how the volatiles change throughout the process of decomposition in chicken liver. Based on this, we will assess how well chicken liver approximates the process of decomposition in a human body. Chicken liver was placed in a sealed mason jar for gases to accumulate in the headspace. A small hole was punctured in the lid of the mason jar and gases were drawn into one of three different solid-phase microextraction (SPME) fibers. After the SPME fiber was left in the jar for five minutes, Gas Chromatography-Mass Spectrometry was used to analyze the volatiles. Preliminary results that show the most common compounds being released from the liver are methyl disulfide, dimethyl trisulfide, dimethoxyflavone, and 1-(3-hydroxypropyl)-2-piperidinone. The results are being compared with published literature to identify important substances in gases that attract blow flies and which sample gives the most reliable results in comparison to a human cadaver. The knowledge gained will be used to assess the appropriate amount of time to age baits to best simulate human cadaver volatiles found in the literature

Diurnal Oviposition of Blow Flies

Blow flies (Diptera: Calliphoridae) are usually the first insects to oviposit (lay eggs) on carrion. The timing of blow fly oviposition is critical for determining a postmortem interval (PMI) estimation, which is the time that has passed between death and corpse discovery. The objective of this investigation was to gain more information about the timing of blow fly oviposition so that a more accurate PMI could be calculated. Past research in our lab has shown that blow fly oviposition occurs an average of 4.75 hours after sunrise. This year’s research expanded on previous studies by placing three piglets in a remote, wooded area one hour after sunrise. The piglets were checked once an hour until oviposition occurred, and it was recorded whether flies and eggs were present each hour. Egg masses were collected. DNA analysis and BLAST were used to identify the individual blow fly species. The timing of oviposition, in hours after sunrise, was analyzed with respect to temperature, humidity, and light intensity. The research was repeated six times in the fall of 2016. Flies were first seen an average of 2.3 hours after sunrise, and oviposition was observed an average of 4.16 hours after sunrise. The average lux reading at the time of oviposition was 26,755 lux, but ranged between 5,790-52,300 lux. This research has importance in both the scientific and forensic communities, as a more accurate PMI can assist with the validity of a forensic investigation