Astigmata: Histiostomatidae) Phoretic on a Forensically Important Blowfly, Chrysomya Villeneuvi (Diptera: Calliphoridae)
Total Page：16
File Type：pdf, Size：1020Kb
Tropical Biomedicine 36(4): 1099–1104 (2019) Short Communication First report of Histiostoma sp. (Astigmata: Histiostomatidae) phoretic on a forensically important blowfly, Chrysomya villeneuvi (Diptera: Calliphoridae) Azmiera, N.1, Mariana, A.2 and Heo, C.C.1,3* 1Faculty of Medicine, Universiti Teknologi MARA, Sungai Buloh Campus, Jalan Hospital, 47000 Sungai Buloh, Selangor, Malaysia 2Unit of Acarology, Infectious Diseases Research Centre, Institute for Medical Research @ National Institutes of Health Malaysia, Jalan Setia Murni U13/52, Seksyen U13 Setia Alam, 40170 Shah Alam, Selangor, Malaysia 3Institute for Pathology, Laboratory and Forensic Medicine (I-PPerForM), Universiti Teknologi MARA, Sungai Buloh Campus, Selangor, Malaysia *Corresponding author e-mail: [email protected] Received 2 June 2019; received in revised form 17 July 2019; accepted 21 July 2019 Abstract. This is the first record of phoretic histiostomatid mites found on a forensically important blow fly species, Chrysomya villeneuvi (Diptera: Calliphoridae), collected from decomposing rabbit carcasses placed in Bukit Lagong Forest Reserve, Sungai Buloh and MARDI Cameron Highlands, Malaysia. The blow flies frequenting around the carcasses were first captured using an insect net. After pinning, they were examined under a stereomicroscope and mites phoretic on their body were carefully removed and preserved in 70% ethanol. Mites were cleared in lactic acid before mounting on slides using Hoyer’s medium and identified under a compound microscope. The flies and their mites were identified as C. villeneuvi and deutonymphs of Histiostoma spp. (Astigmata: Histiostomatidae), respectively. This insect- mite association may be useful to provide insights regarding the minimum post-mortem interval and the location of death in forensic entomological investigations. The identification of insect species allows rufifacies, Chrysomya nigripes and forensic entomologists to link the duration Chyrosmya villeneuvi (Kavitha et al., 2013). of the developmental stages of insects for Phoresy is the process where mites minimum post-mortem interval (mPMI) attached themselves to animals or other determination (Turchetto & Vanin, 2004). arthropod hosts while restricting their own Necrophagous insects such as flies and development and feeding behaviour for beetles are commonly utilized for this dispersal (Farish & Axtel, 1971). A survey purpose in forensic investigations (Byrd, in Brazil reported few findings of phoretic 2000; Kulshrestha & Satpathy, 2001). Flies, mesostigmatid mites on necrophagous flies especially Calliphoridae or blow flies, helped (Sato et al., 2018). As for astigmatid mites, providing valuable mPMI estimation as phoresy is commonly found in the families they are usually the primary colonisers to Acaridae and Histiostomatidae (OConnor, decomposing bodies (Eberhardt & Elliot, 2009). Within Histiostomatidae, Myianoetus 2008; Martin-Vega et al., 2017). In Malaysia, muscarum was found in abundance on flies that are frequently associated with muscid flies, Synthesiomyia nudiseta, forensic cases are Calliphoridae such as which were collected from human remains Chrysomya megacephala, Chrysomya (Pimsler et al., 2016). Another member of 1099 the same family, which was often reported Lagong Forest Reserve, Sungai Buloh, on carcasses (Goff et al., 1986; OConnor, Selangor, (3.25°N 101.616667°E, 368 m 2009), beetles (e.g., Trogidae) and flies above sea level (a.s.l)) and MARDI Cameron (e.g., Sciaridae and Phoridae), was from Highlands (4.468029°N 101.384754°E, 1450 genus Histiostoma (Perotti et al., 2010). To m a.s.l.). The study was conducted for 4 date, there is no report of these mites on months, from July 2018 to October 2018. The Calliphoridae in Malaysia. blowflies were captured daily at 0900 (1 hour The specificity of mites to their per day) from fresh stage of decomposition microhabitats and their life cycles has been until advanced decay stage of rabbit used as supporting data in a few crime carcasses. A killing jar containing cotton balls investigations (Hani et al., 2018; Kwak & soaked in absolute ethyl acetate was used Schubert, 2019). As for death investigations, to kill the collected adult flies. The dead flies mites assisted by confirming location of were subsequently pinned on the right side crime scenes and the possible environment of the upper thorax region before placing in which the victim might have been them in the oven at 40°C for 4–5 days for previously exposed (Szelecz et al., 2018). dehydration purposes. Blow fly specimens Mites, especially the phoretic ones, have were then identified at genus and species been beneficial to determine the estimated levels by using Greenberg & Kunich (2002) mPMI in various cases (Gonzalez-Medina prior to their labelling. They were examined et al., 2013; Kamaruzaman et al., 2018). In under a stereomicroscope (Olympus SZ51, Malaysia, the studies of Acari for forensic Japan) and mites that phoretic on the body purposes are still scarce (Azima et al., 2011; regions of the flies were carefully removed Silahuddin et al., 2015). Therefore, it is using a fine brush and preserved in 70% imperative to report any related finding of ethanol. A total of 20 phoretic mites (10 phoretic mites and their respective insect random mites from all infested blow flies hosts collected from carrion or their collected in both study locations) were surrounding in this country for further cleared in lactic acid, mounted on slides forensic evaluation and applications. This using Hoyer’s medium and observed under paper reports the first finding of Histiostoma a compound microscope (Olympus BX53, spp. on a forensically important blow fly, Japan) for their identification based on C. villeneuvi from decomposing rabbit common mites’ morphological keys (Krantz carcasses placed in Bukit Lagong Forest & Walter, 2009; Negm & Alatawi, 2011). The Reserve, Selangor, and the Malaysian host blow flies were identified as C. Agricultural Research and Development villeneuvi and their phoretic mites were Institute (MARDI) at Cameron Highlands, Histiostoma spp. Pahang, Peninsular Malaysia. The total number of collected blow flies The blow flies surrounding rabbit were 262 and 116 in Bukit Lagong Forest (Oryctolagus cuniculus) carcasses were Reserve and MARDI Cameron Highlands, captured using an insect net from Bukit respectively (Table 1). There were approxi- Table 1. The total number of blow flies according to species collected from the study sites in Bukit Lagong Forest Reserve and MARDI Cameron Highlands Abundance of adult Diptera collected Adult Diptera Bukit Lagong Forest Reserve MARDI Cameron Highlands Chrysomya megacephala 40 58 Chrysomya rufifacies 112 26 Chrysomya villeneuvi 45 16 Hypopygiosis violacea 50 Lucillia cuprina 60 0 Unidentified species 0 16 Total 262 116 1100 mately 150 deutonymphs of Histiostoma decomposition, the carrion resource became spp. found phoretic on several adults C. limited for the existing arthropods. Therefore, villeneuvi. The finding of phoretic mites could for survival purposes, the astigmatid mites, be related to the unique behaviour of C. Histiostoma spp. rode on possibly newly villeneuvi where the males eclosed from its emerged adults, C. villeneuvi from the pupa earlier than the females and waited for carcasses, in order to move to a more the females in order to secure a successful resourceful environment (e.g., new carrion). copulation (Omar et al., 1994). The time taken The evidence of finding Histiostoma spp. by the male flies while waiting for the females on the thorax and abdomen of C. villeneuvi provides ample time for the mites to attach at both study locations indicated that one of themselves on the body of the flies. the common insect hosts for Histiostoma The host flies were captured in both spp. is C. villeneuvi. study locations; on Day 16 postmortem in The histiostomatid mites may be useful Bukit Lagong Forest Reserve and on Day 18 as an indicator in cases where the dead post-mortem at MARDI, Cameron Highlands body was not at the crime scene or has been when the rabbit carcasses were already at removed from its original location. The mites the advanced decay stage. In Bukit Lagong might indicate the body has been moved from Forest Reserve, it took 7 days for the rabbits the original crime/death scene after it has to reach the advanced decay stage at the been decomposed at the advanced decay average temperature of 25.5° and mean stage. The specificity of Acari to their precipitation 2.9 mm. Meanwhile in MARDI, microhabitat has proven that it can be used Cameron Highlands, the rabbit carcasses as the geographical indicator in forensic took longer time to reach the advanced investigations. The finding of synanthropic decay stage which was at Day 11 with the mites, Sancassania berlesei (Astigmata: average temperature of 22.1° and the Acaridae) and Macrocheles matrius mean precipitation of 0.8 mm. A similar (Mesostigmata: Macrochelidae) on the decomposition study showed that rabbit human bones found in Swiss forest indicated carcasses reached the advanced decay that the victims were first murdered stage at Day 17 in Cameron Highlands elsewhere before being buried there (Szelecz (Silahuddin et al., 2015). The finding of et al., 2018). The detection of mites specific phoretic Histiostoma spp. at this advanced to the Australasia region has helped to solve decay stage coincided with previous forensic a robbery case by narrowing down the reports of Acari collection from animal location of the robbed money (Hani et al.,