Climate change and diminishing seasonality in Arctic benthic processes

The iconic picture of Arctic marine ecosystems shows an intense pulse of biological productivity around the spring bloom that is sustained while fresh organic matter (OM) is available, after which ecosystem activity declines to basal levels in autumn and winter. We investigated seasonality in benthic biogeochemical cycling at three stations in a high Arctic fjord that has recently lost much of its seasonal ice-cover. Unlike observations from other Arctic locations, we find little seasonality in sediment community respiration and bioturbation rates, although different sediment reworking modes varied through the year. Nutrient fluxes did vary, suggesting that, although OM was processed at similar rates, seasonality in its quality led to spring/summer peaks in inorganic nitrogen and silicate fluxes. These patterns correspond to published information on seasonality in vertical flux at the stations. Largely ice-free Kongsfjorden has a considerable detrital pool in soft sediments which sustain benthic communities over the year. Sources of this include macroalgae and terrestrial runoff. Climate change leading to less ice cover, higher light availability and expanded benthic habitat may lead to more detrital carbon in the system, dampening the quantitative importance of seasonal pulses of phytodetritus to seafloor communities in some areas of the Arctic. This article is part of the theme issue 'The changing Arctic Ocean: consequences for biological communities, biogeochemical processes and ecosystem functioning'.

Protective Action of Ostreococcus tauri and Phaeodactylum tricornutum Extracts towards Benzo[a]Pyrene-Induced Cytotoxicity in Endothelial Cells

Marine microalgae are known to be a source of bioactive molecules of interest to human health, such as n-3 polyunsaturated fatty acids (n-3 PUFAs) and carotenoids. The fact that some of these natural compounds are known to exhibit anti-inflammatory, antioxidant, anti-proliferative, and apoptosis-inducing effects, demonstrates their potential use in preventing cancers and cardiovascular diseases (CVDs). Benzo[a]pyrene (B[a]P), a polycyclic aromatic hydrocarbon (PAH), is an ubiquitous environmental pollutant known to contribute to the development or aggravation of human diseases, such as cancer, CVDs, and immune dysfunction. Most of these deleterious effects are related to the activation of the polycyclic aromatic hydrocarbon receptor (AhR). In this context, two ethanolic microalgal extracts with concentrations of 0.1 to 5 µg/mL are tested, Ostreoccoccus tauri (OT) and Phaeodactylum tricornutum (PT), in order to evaluate and compare their potential effects towards B[a]P-induced toxicity in endothelial HMEC-1 cells. Our results indicate that the OT extract can influence the toxicity of B[a]P. Indeed, apoptosis and the production of extracellular vesicles were decreased, likely through the reduction of the expression of CYP1A1, a B[a]P bioactivation enzyme. Furthermore, the B[a]P-induced expression of the inflammatory cytokines IL-8 and IL1-β was reduced. The PT extract only inhibited the expression of the B[a]P-induced cytokine IL-8 expression. The OT extract therefore seems to be a good candidate for counteracting the B[a]P toxicity.

PAHs increase the production of extracellular vesicles both in vitro in endothelial cells and in vivo in urines from rats

Environmental contaminants, to which humans are widely exposed, cause or worsen several diseases, like cardiovascular diseases and cancers. Among these molecules, polycyclic aromatic hydrocarbons (PAHs) stand out since they are ubiquitous pollutants found in ambient air and diet. Because of their toxic effects, public Health agencies promote development of research studies aiming at increasing the knowledge about PAHs and the discovery of biomarkers of exposure and/or effects. Extracellular vesicles (EVs), including small extracellular vesicles (S-EVs or exosomes) and large extracellular vesicles (L-EVs or microvesicles), are delivery systems for multimolecular messages related to the nature and status of the originating cells. Because they are produced by all cells and detected within body fluids, EV releases could act as cell responses and thereby serve as biomarkers. To test whether EVs can serve as biomarkers of PAHs exposure, we evaluate the effects of these pollutants on EV production using an in vitro approach (human endothelial cell line, HMEC-1) and an in vivo approach (urine samples from PAHs-exposed rats). Our study indicates that, i) PAH exposure increases in vitro the EV production by endothelial cells and in vivo the release of EVs in urine, and that the stimulating effects of PAHs concern both S-EVs and L-EVs; ii) PAH exposure and more particularly exposure to B[a]P, can influence the composition of exosomes produced by endothelial cells; iii) the aryl hydrocarbon receptor, a cytosolic receptor associated to most deleterious effects of PAHs, would be involved in the PAH effects on the release of S-EVs, but not L-EVs. These results suggest that EVs may have utility for monitoring exposure to PAHs, and more particularly to B[a]P, considered as reference PAH, and to detect the related early cellular response prior to end-organ damages.

Morphine extraction in necrophagous insects remains for determining ante-mortem opiate intoxication

To study the potential use of insects remains as toxicological indicators, we measured morphine in desiccated entomological materials using a radioimmunoassay method (Coat-A-Count Serum Morphine, Dade Behring, France) following enzymatic hydrolysis.First, enzymatic cuticle extraction of morphine (pronase digestion preceded by a 2h incubation with a dithiothreitol solution) was performed on various substrates (Calliphoridae puparial cases and desiccated adults, and desiccated pupae of Dermestidae) which were then tested to identify possible interferences with the radioimmunoassay procedure. This same procedure was performed on puparial cases and desiccated adults of Lucilia sericata (Diptera, Calliphoridae) previously reared on minced meat containing various morphine concentrations. Morphine was detected only in cuticle powder from insects reared on meats containing 100 and 1000mg/kg. Higher concentrations were measured in puparial cases. Rearings on psoas from eight heroin overdose victims confirmed previous experimental results. Remains of necrophagous insects, particularly puparial cases, are often preserved for a long time, and consequently can serve as late alternative specimens for toxicological analysis when suitable tissues are not available.

Entomotoxicology

Entomotoxicology is a relatively new branch of forensic entomology. The potential use of insects for detecting drugs and other toxins in decomposing tissues has been widely demonstrated. In death investigations, Diptera and other arthropods can be reliable alternate specimens for toxicological analyses in the absence of tissues and fluids normally taken for such purposes. Entomotoxicology also investigates the effects caused by drugs and toxins on arthropod development in order to assist the forensic postmortem interval estimates. However, several remarks on the limitations of entomotoxicology have been highlighted recently. In this paper, the implications for the practice of this forensic procedure are fully reviewed.

Effects of temperature and intraspecific interaction on the development of Dermestes maculatus (Coleoptera: Dermestidae)

Studies were conducted to determine development rates of of Dermestes maculatus DeGeer at temperatures of 15, 20, 25, 30, and 35 degrees C. No individuals completed development to the adult stage at 15 degrees C. For the other temperatures, survivorship ranged from 9.3% at 20 degrees C to 36% at 35 degrees C. Time required for development varied inversely with temperature from a mean of 89.7 d at 20 degrees C to 36.4 d at 35 degrees C. For specimens held individually, survivorship was higher at 25 and 30 degrees C, i.e., 83.2 and 60.2%, respectively. No specimens held individually at 35 degrees C survived past the first larval instar. Mortality during the egg stage at 25 and 30 degrees C was 4.52-5.23%, whereas mortality during the first instar was significantly higher for the individuals held at 30 degrees C and 100% for those at 35 degrees C. There was an inverse relation observed between larval density and both survivorship and mean adult weights.

Immunohistochemical contribution to the study of morphine metabolism in Calliphoridae larvae and implications in forensic entomotoxicology

Morphine was detected by immunohistochemistry on sections of third stage larvae of Calliphora vomitoria (Diptera, Calliphoridae) reared on minced beef meat previously treated with morphine hydrochloride. The detection was performed with an avidin-biotin-peroxidase-complex method. Positive specimens showed specific staining of the haemolymph and a more intense immunoreaction in an area located at the limit between exocuticle and endocuticle. These results constitute an evidence of morphine accumulation inside the cuticle of Diptera larvae during their development. During the pupariation, the larval cuticle is transformed into the sclerotized puparium. This study consequently points out the possibilities of analyzing empty pupariae when suitable tissues or living necrophagous insects are absent.

Determination of drug levels in two species of necrophagous Coleoptera reared on substrates containing morphine

Two species of necrophagous Coleoptera: Dermestes frischi (Dermestidae) and Thanatophilus sinuatus (Silphidae), were reared on substrates containing different amounts of morphine. Colonies of D. frischi were reared on rabbit carcasses which had been given 10, 20, and 40 mg/h of morphine hydrochloride via ear artery perfusion over a 3 h period prior to death. A fourth rabbit served as a control. T. sinuatus was reared on minced beef spiked with morphine hydrochloride to give concentrations of 1,000, 2,500, 5,000, and 10,000 ng/g and one control colony. These dosages were calculated to create tissue concentrations of morphine similar to those encountered in human deaths due to morphine overdose. Larvae. pupae, and adults (except for T. sinuatus) were analyzed for morphine content. All developmental stages of D. frischi were positive for morphine and concentrations correlated with cadaveric tissue concentrations during larval stages and to a lesser extent in the adult stage. For T. sinuatus, the best correlations were found in 2nd and 3rd instar larvae. This study demonstrates the potential for use of necrophagous Coleoptera, as well as Diptera larvae, as alternate specimens for toxicological analyses.

Determination of drug levels in larvae of Protophormia terraenovae and Calliphora vicina (Diptera: Calliphoridae) reared on rabbit carcasses containing morphine

Two species of blow flies (Diptera: Calliphoridae) were reared on tissues from rabbits administered different dosages of morphine. These species, Protophormia terraenovae and Calliphora vicina are among the first wave of insects colonizing a dead body. Two series of 3 rabbits were given dosages of 10, 20, and 40 mg/h of morphine over a 3 h period via ear artery perfusion. A morphine blood level plateau was attained after 1 h of perfusion. Two other rabbits were used as controls. Samples of tissues collected from rabbits using a coelioscopic technique were determined to have morphine concentrations similar to those encountered in human overdoses and were correlated with dosages of morphine administered. All samples from control rabbits were negative for morphine. Larvae and puparia of both species were regularly collected from each rabbit for toxicological analysis. Concentrations of morphine in larvae reared on rabbit carcasses containing morphine were significantly lower than concentrations found in the tissues. There was a decrease in concentration in morphine observed in transition from feeding 3rd instar larva to puparium. A correlation between larval concentration and tissue concentration was found only in feeding 3rd instar larvae.

Epidermoptid mange in Laysan albatross fledglings in Hawaii

Mange caused by the epidermoptid mite Myialges nudus (Acari: Epidermoptidae) is described in 31 dead fledgling Laysan albatrosses (Phoebastria immutabilis) from Midway Atoll (Hawaii, USA) sampled from 18 June to 10 July 1990 and from 21 June to 22 July 1991. This is the first record for this parasite from this host. Mites were collected from the skin; were located primarily in the stratum corneum; and were associated with mild to severe granulomatous inflammation, hyperkeratosis, dermal edema, ballooning degeneration of keratinocytes, neovascularization, and subdermal fibrosis. The severity of inflammation in some birds suggested that dermatitis due to M. nudus could be a significant cause of morbidity, or even mortality, in these birds.

Comparison of patterns of decomposition in a hanging carcass and a carcass in contact with soil in a xerophytic habitat on the Island of Oahu, Hawaii

Decomposition studies were conducted to determine differences in rates and patterns of decomposition of carcasses hanging and exposed on the surface of the soil. These studies were conducted between 17 October and 17 December 1997 inside of Diamond Head Crater on the island of Oahu, Hawaii. The animal model was the domestic pig. Sus scrofa. The rate of biomass removal from the hanging carcass was significantly slower than that observed for the control carcass during the bloat and decay stages of decomposition. Internal temperatures for the control carcass were elevated above the ambient air temperatures during the earlier stages of decomposition (bloated and decay), while those recorded for the hanging carcass approximated the ambient air temperatures. There was a greater diversity of arthropod species recorded and numbers of individuals observed were higher for the control carcass. A significant site of arthropod activity was observed on the surface of the soil immediately under the hanging carcass and this became the primary site of arthropod activity as decomposition progressed.

Decomposition patterns in terrestrial and intertidal habitats on Oahu Island and Coconut Island, Hawaii

Decomposition studies were conducted at two sites on the Island of Oahu, Hawaii, to compare patterns of decomposition and arthropod invasion in intertidal and adjacent terrestrial habitats. The animal model used was the domestic pig. One site was on Coconut Island in Kaneohe Bay on the northeast side of Oahu, and the second was conducted in an anchialine pool located at Barber's Point Naval Air Station on the southwest shore of Oahu. At both sites, the terrestrial animal decomposed in a manner similar to what has been observed in previous studies in terrestrial habitats on the island of Oahu. Rate of biomass depletion was slower in both intertidal studies, and decomposition was primarily due to tide and wave activity and bacterial decomposition. No permanent colonization of carcasses by insects was seen for the intertidal carcass at Coconut Island. At the anchialine pool at Barber's Point Naval Air Station, Diptera larvae were responsible for biomass removal until the carcass was reduced below the water line and, from that point on, bacterial action was the means of decomposition. Marine and terrestrial scavengers were present at both sites although their impact on decomposition was negligible. Five stages of decomposition were recognized for the intertidal sites: fresh, buoyant/floating, deterioration/disintegration, buoyant remains, and scattered skeletal.

Two new species of chiggers (Acari: Trombiculidae and Leeuwenhoekiidae) from Iran

Odontacarus khanjani Goff & Saboori (Leeuwenhoekiidae) and Neotrombicula iranensis Goff & Saboori (Trombiculidae) were described as new. Both species were collected as unengorged larvae on alfalfa plants, Medicago sativa, in western Iran.

Arthropod succession patterns onto burnt carrion in two contrasting habitats in the Hawaiian Islands

Decomposition studies were conducted using carcasses of domestic pigs, Sus scrofa L., one burned and the other unburned (the control) to determine effects of burning on arthropod succession patterns. The burnt carcass corresponded to a CGS level #2 burn victim. The studies were conducted in two contrasting habitats, both on the island of Oahu. The first was conducted in a xerophytic habitat from 1 Sept. 1995 through 1 Oct. 1995 while the second was conducted in a rainforest habitat from 29 April 1996 to 28 May 1996. No marked differences were noted in arthropod fauna present or the duration of the stages of decomposition between the carcasses at either site. The major oviposition by flies of the family Calliphoridae occurred one day earlier on the burnt carcass than the control carcass at Diamond Head and four days earlier at Lyon Arboretum. This resulted in all successional waves onto the burnt carcass occurring one day earlier at Diamond Head and four days earlier at Lyon Arboretum. These differences could alter a postmortem interval estimate based on arthropod succession patterns by up to 24 hours and 4 days, respectively.

Estimation of postmortem interval based on colony development time for Anoplolepsis longipes (Hymenoptera: Formicidae)

The postmortem interval for a set of human remains discovered inside a metal tool box was estimated using the development time required for a stratiomyid fly (Diptera: Stratiomyidae), Hermetia illucens, in combination with the time required to establish a colony of the ant Anoplolepsis longipes (Hymenoptera: Formicidae) capable of producing alate (winged) reproductives. This analysis resulted in a postmortem interval estimate of 14 + months, with a period of 14-18 months being the most probable time interval. The victim had been missing for approximately 18 months.

The genus Hexidionis (Acari:Trombiculidae) with the description of a new species from Texas

Hexidionis garfieldi is described as new from specimens collected off a domestic cat. Felis silvestris f. catus Schreber, in Corpus Christi, TX. The genus Hexidionis Vercammen-Grandjean & Loomis, 1967, is rediagnosed and a key to the 11 included species given.

Arthropod succession on exposed carrion in three contrasting tropical habitats on Hawaii Island, Hawaii

Decomposition studies were conducted using domestic pig carcasses to determine arthropod succession patterns on exposed carrion for the island of Hawaii. The carcasses were placed in upland forest and woodland (1,877 m), rainforest (1,169 m) and midelevation woodlands (646 m) habitats. Marked differences in species composition, rates of biomass removal, and succession patterns were observed between these 3 sites. These results also differed from patterns observed during previous decomposition studies conducted on the island of Oahu.

Effects of 3,4-methylenedioxymethamphetamine in decomposing tissues on the development of Parasarcophaga ruficornis (Diptera:Sarcophagidae) and detection of the drug in postmortem blood, liver tissue, larvae, and puparia

Larvae of Parasarcophaga ruficornis (Fabricius) (Diptera: Sarcophagidae) were reared on tissues from rabbits administered different dosages of 3,4-methylenedioxymethamphetamine to study the effects of this drug on the development of this insect species. The rabbits were given 11, 22.5, and 67 mg of the drug via ear vein infusion. These dosages correspond to a 0.5, 1.0, and 2.0 median lethal dose. Larvae from colonies fed on tissues from the rabbit receiving 67 mg and the control developed more rapidly from hours 24 through 114. The period required for completion of larval development was significantly shorter for the larvae from the colony fed on liver tissues from the rabbit receiving the 67 mg dosage. This colony also had the lowest total mortality rate during development. No significant differences were observed among the colonies in the duration of the puparial period. Analyses by liquid chromatography/mass spectrometry of the larvae and empty puparial cases following base extraction detected the drug in quantities directly related to the dosage of the drug administered to the rabbits serving as a food source. These results have implications for the determination of time since death when gauged by the development of this insect species.

External ophthalmomyiasis, a disease established in Hawaii

External ophthalmomyiasis, usually caused by the sheep nasal bot fly, Oestrus ovis L., is characteristically a benign disorder in humans, but may rarely cause severe complications. It occurs on most of the inhabited Hawaiian islands, and is more common than indicated by previously published reports. A typical case is presented along with the fly's life cycle, clinical features, and management.

New genus and six new species of chiggers (Acari: Trombiculidae and Leeuwenhoekiidae) collected from small mammals in Argentina

Argentinacarus. n. gen., is proposed with Argentinacarus expansus, n. sp., off Irenomys tarsalis and Akodon longipilis, as type species. Quadraseta akodonica, off Akodon longipilis and Auliscomys micropus, Colicus sinpretarsus, off Histiotus montanus, Parasecia argentinensis off Phyllotis xanthopygus, Parasecia neuquenensis, off Akodon longipilis, and Andalgalomacarus xanthopyga, off Phyllois xanthopygus and Eligmodontia morgani, are described as new. All specimens were collected in Argentina.

New species of Neotrombicula (Acari: Trombiculidae) from African primates (Galagidae and Cercopithecidae)

Neotrombicula kenyaensis Goff and Neotrombicula centrafricana Goff are described as new from specimens collected from the primates Galago senegalensis E. Geoffroy (Fam. Galagidae) in Kenya and Allenopithecus nigroviridis (Pocock) (Fam. Cercopithecidae) in Central Africa, respectively.

Entomotoxicology. A new area for forensic investigation

Insects and other arthropods can be valuable tools in death investigations. In addition to their use in the estimation of postmortem intervals, insects may serve as reliable alternate specimens for toxicological analyses in the absence of tissues and fluids normally taken for such purposes. Recent research has also demonstrated that the presence of drugs and/or toxins in decomposing tissues may alter the rate and patterns of development in arthropods using such tissues as food, thus potentially altering estimates of the postmortem interval. Current advances in the use of arthropods as alternate toxicological specimens and the effects of various drugs and toxins on arthropod development are reviewed here.

Preliminary observations of the effects of phencyclidine in decomposing tissues on the development of Parasarcophaga ruficornis (Diptera: Sarcophagidae)

Larvae of Parasarcophaga ruficornis (Fabricius) (Diptera: Sarcophagidae) were reared on tissues from rabbits administered different dosages of phencyclidine to study the effects of this drug on the development of this insect species. The rabbits were given 3.66, 7.31, and 14.62 mg of phencyclidine via ear vein infusion. No significant differences in larval growth rate were observed among the colonies, although the duration of the non-feeding portion of the third instar was shorter for larvae fed on tissues containing the drug. Mortality during the larval stage was directly related to the dosage of phencyclidine administered, ranging from 0 in the control colony to 29.0% in the colony fed on tissues from the rabbit receiving 14.62 mg of phencyclidine. Durations of the puparial stage were longer for colonies fed on tissues containing the drug. Presence of phencyclidine was detected in larvae from all colonies fed on tissues from rabbits receiving the phencyclidine using GC/MS.

The black soldier fly Hermetia illucens (Diptera: Stratiomyidae) as a potential measure of human postmortem interval: observations and case histories

The black soldier fly, Hermetia illucens (L.), has been shown to be a ubiquitous inhabitant of both surface and buried human remains throughout the southern, central and western United States and Hawaii. Unlike most other species of forensically important Diptera, this species frequently dominates bodies in the dry/post decay stage of decomposition. Adults of the black soldier fly appear to initiate oviposition (egg laying) 20 to 30 days postmortem. Even at warm temperatures (27.8 degrees C), subsequent completion of the life cycle can require an additional 55 days. Life history data for H. illucens, when used in combination with data for other cohabiting arthropod species and viewed in the context of local environmental conditions, can provide medicolegal investigators with valuable parameters for estimating the postmortem intervals for badly decomposed remains.

Estimation of Postmortem Interval Using Arthropod Development and Successional Patterns

Insects are frequently the first organisms to arrive at a dead body. By their activities they begin a biological clock that will allow for an estimation of the postmortem interval (PMI). In this publication, the two general approaches to estimation of the PMI using entomological data are reviewed: (a) use of individual species developmental patterns; and (b) use of arthropod succession data. Recent advances in studies of the biologies of various Diptera (flies) have allowed for more accurate estimates, as have recent detailed studies of the roles of various arthropods in the decomposition process. Five stages of decomposition (fresh, bloated, decay, post-decay, and skeletal) are suggested as reference points in the decomposition process. These stages are largely artificial, but serve as convenient references in court situations. Factors that may delay invasion of the remains by arthropods or alter developmental patterns, such as wrapping of the body, climate, or presence of drugs and toxins in the remains, are discussed. A general plan of approach to the estimation of PMI using entomological data is presented.

Preliminary observations of the effects of amitriptyline in decomposing tissues on the development of Parasarcophaga ruficornis (Diptera: Sarcophagidae) and implications of this effect to estimation of postmortem interval

Larvae of Parasarcophaga ruficornis (Fabricius) (Diptera: Sarcophagidae) were reared on tissues from rabbits administered different dosages of amitriptyline to study the effects of this drug on the development of this insect species. The rabbits were given 300, 600, and 1000 mg of amitriptyline via ear vein infusion. No significant differences in rates of larval growth were observed among the colonies. Durations of the larval stage were significantly longer for larvae fed on tissues from rabbits receiving amitriptyline. Larval mortality was observed to be 5.5% for the control colony, but ranged from 40.5 to 57.5% for the test colonies. Durations of the puparial stage were significantly longer for the colonies fed on tissues from the rabbits receiving the 600 and 1000 mg dosages of amitriptyline than for the control and colony fed on tissues from the rabbit receiving the 300 mg dosage. Observed differences in the durations of the larval and pupal stages from the test colonies were sufficient to alter a postmortem interval estimate by up to 77 h, if based on normal developmental patterns for this species at 26 degrees C. Presence of amitriptyline and nortriptyline could be detected in larvae from all colonies fed on tissues from the rabbits receiving amitriptyline using high-performance liquid chromatography (HPLC).

A BASIC algorithm for calculating the postmortem interval from arthropod successional data

A computer algorithm, implemented in the BASIC language, is presented for calculating the postmortem interval (PMI) from arthropod successional data. Entomology-assisted determination of the PMI promises to be a reliable technique in cases of homicide, suicide, accidental death, and unattended death due to natural causes. The program requires, as input, the identity of arthropod taxa recovered from human remains in a death scene investigation and machine-readable data on carrion-associated arthropod taxa and their known successional patterns of activity for the same geographical area. The program performs rapid comparisons of these lists and, on output, calculates an upper and lower estimate of the PMI, identifies the definitive taxa for these limits, and determines if the remaining corpse taxa have known successional patterns that are consistent for this estimate. An alternate output is provided if one or more corpse taxa do not overlap all the others at any single time in the succession. In that event, the user is prompted to recheck the identity of the non-overlapping taxon or taxa or reevaluate the environmental circumstances surrounding the case in question. Results of the analysis are saved to an ASCII file for output to a printer for making paper copies useful for the entomologist's Case Study Final Report. This program may make possible wider use of this technique in law enforcement and medical investigator offices that utilize both forensic entomologist expertise and IBM PCs (or compatible computers).

Preliminary observations of the effect of methamphetamine in decomposing tissues on the development rate of Parasarcophaga ruficornis (Diptera: Sarcophagidae) and implications of this effect on the estimations of postmortem intervals

Larvae of Parasarcophaga ruficornis (Fabricius) (Diptera: Sarcophagidae) were reared on tissues from rabbits administered different dosages of methamphetamine to study the effects of this drug on development of this species. The rabbits were given 37.5, 71.4, and 142.9 mg of methamphetamine via ear vein infusion. From Hours 30 to 60, larvae feeding on tissues from rabbits receiving 71.4 and 142.9 mg of methamphetamine developed more rapidly than larvae from the control colony and those feeding on tissues from the rabbit receiving 37.5 mg of methamphetamine. The time required for pupariation was significantly greater for colonies fed on tissues from methamphetamine-dosed rabbits than for the control. These differences were sufficient to alter postmortem interval estimates based on larval development by up to 18 h and estimates based on puparial development by up to 48 h. The presence of methamphetamine or amphetamine could not be detected in Diptera larvae in this experiment using radioimmunoassay techniques, as there was a nonspecific reaction, resulting in a false positive.

Presence of fecal material in diapers as a potential source of error in estimations of postmortem interval using arthropod development rates

Second instar larvae of the fly Chrysomya megacephala (Diptera, Calliphoridae) were recovered from the diapers of a 16-month-old child abandoned by her mother on Oahu, Hawaii. The development of these larvae indicated a minimum period of 23.5 h of exposure prior to discovery of the child. Larvae of this species of fly are not normally associated with living tissues in Hawaii, but rather with feces and remains during the early stages of decomposition. Had the child in this case died and data not been provided detailing the site of infestation, the postmortem interval estimated would have been significantly longer than was actually the case, because of the development of the larvae inside the diapers of the living child. The need for caution in cases involving deaths of infants, the elderly, and individuals not capable of caring for themselves is stressed.

Effect of carcass size on rate of decomposition and arthropod succession patterns

Decomposition studies were conducted using two carcasses of domestic pigs, Sus scrofa L., 8.4 kg and 15.1 kg in weight, to determine the effects of carcass size on the rate of decomposition, composition of the arthropod fauna, and succession patterns. A total of 46 arthropod taxa were recovered during this study. No size-related differences were observed between carcasses with respect to composition of the arthropod fauna or patterns of succession. A greater number of arthropods were observed attracted to the 15.1-kg carcass, and the rate of decomposition observed was more rapid for the 15.1-kg carcass than for the 8.4-kg carcass. Internal temperatures of the 8.4-kg carcass were more directly related to external ambient temperatures during the fresh and bloated stages of decomposition. During the decay stage, both carcasses generated internal temperatures significantly above ambient temperatures. Following this stage, internal temperatures fell to approximate ambient temperatures during the postdecay and remains stages.

Comparison of insect species associated with decomposing remains recovered inside dwellings and outdoors on the island of Oahu, Hawaii

A comparison of insects collected from 35 cases of decomposing remains on the island of Oahu, Hawaiian Islands (14 from indoor situations and 21 from outdoors), yielded a total of 22 species of insects in 3 orders and 12 families. Of these, five species were recovered in both indoor and outdoor situations. Remains recovered indoors had a greater variety of Diptera larvae associated with them, while remains discovered outdoors had a greater variety of Coleoptera species present. Some species of insects were restricted to remains discovered indoors, while others were found only associated with remains in outdoor situations. Knowledge of the species of insects associated with different habitats may serve to provide information concerning the history of the remains.

Determination of postmortem interval by arthropod succession: a case study from the Hawaiian Islands

A postmortem interval of 34 to 36 days was established for remains recovered on the island of Oahu, Hawaii, based on interpretations of patterns of arthropod succession on the remains. This interval was primarily based on the presence of adult specimens of Philonthus longicornis (family Staphylinidae), mature larvae of Piophila casei (family Piophilidae), and empty puparial cases of Chrysomya rufifacies (family Calliphoridae). Species and developmental stages of two additional Coleoptera species and three additional Diptera species were also present, which was consistent with the estimated interval, although not definitive.

Effect of heroin in decomposing tissues on the development rate of Boettcherisca peregrina (Diptera, Sarcophagidae) and implications of this effect on estimation of postmortem intervals using arthropod development patterns

Larvae of the flesh fly Boettcherisca peregrina (Robineau-Desvoidy) were reared on the tissues of rabbits to study the effects of heroin on the development rates of this species. The rabbits were given 6, 12, 18, and 24 mg of heroin by cardiac puncture. From Hours 18 to 96, larvae feeding on tissues containing heroin (as morphine) developed more rapidly than those feeding on tissues from the control. The time required for pupation was significantly greater for colonies fed on tissues from heroin-dosed rabbits than for the control colony. The differences observed in the rates of development were sufficient to alter postmortem interval estimates based on larval development by up to 29 h and estimates based on pupal development by 18 to 38 h.

Detection of organophosphate poisoning in a putrefying body by analyzing arthropod larvae

Deaths as a result of organophosphate poisoning are usually detected by analysis of body fluids and tissues for the presence of the toxic agent. These procedures present particular difficulties when performed on remains in an advanced stage of decomposition. Malathion poisoning was suspected in a case in which the remains were in an advanced stage of decomposition and the presence of malathion was confirmed by analyses of gastric content and body fat. Two species of fly larvae, Chrysomya megacephala (Fabricius) and Chrysomya rufifacies (Macquart), were present on the remains. A sample of these larvae was analyzed for malathion content. A total of 574 micrograms of malathion was detected in 0.26 g of pooled larvae, or a level corresponding to 2050 micrograms/g of larvae. Presence of organophosphates in arthropod larvae has not been documented previously and the analysis of larvae from decomposing remains may prove a useful technique for detection of these toxicants in decomposing remains.

Estimation of postmortem interval by arthropod succession. Three case studies from the Hawaiian Islands

Three instances of estimation of postmortem interval using computer-assisted entomological techniques on the island of Oahu in the Hawaiian Islands are presented. While postmortem intervals were similar for all cases (4-5 1/2 days), recovery of the remains in differing habitats (xerophytic, mesophytic, and swamp) on the island resulted in significant differences in gross appearance of the remains, which could have resulted in the determination of different postmortem intervals in the absence of entomological techniques.

Forensic entomology in the Hawaiian Islands. Three case studies

Three instances of the use of entomological techniques for the estimation of postmortem interval in homicide cases on the island of Oahu, Hawaiian Islands, are presented. These cases represent differing stages of decomposition and range from 8 to 53 days postmortem.

The genus Speleocola lipovsky (Acari: Trombiculidae) with descriptions of two new species from Venezuela

Speleocola Lipovsky 1952 is redescribed. New species S. clangula off Rhipidomys sp., Venezuela, and S. nolae off Peropteryx kappleri, Venezuela, are described. A key to the 5 included species is given.

Keys to the genera of chiggers of the western hemisphere (acarina: trombiculidae)

Synotpic keys to the 87 genera of chiggers in the Western Hemisphere (Nearctic and Neotropical regions) as well as illustrations to the terminology employed, are presented.