Observations of the third instar larva and puparium of Chrysomya bezziana (Diptera: Calliphoridae)

Observations on the ultrastructure of the third instar larva and puparium of the Old World screw-worm fly, Chrysomya bezziana, are presented utilizing both light microscopy (LM) and scanning electron microscopy (SEM). Results of this study indicate that the shape of the intersegmental spines between the pro- and mesothorax markedly differ from other blow fly species (Chrysomya megacephala, Chrysomya rufifacies, Chrysomya nigripes, Lucilia cuprina) in being broad-based with sharp recurved tips. Other characters such as the posterior spiracles, number of papillae on the anterior spiracles, oral grooves, and posterior spiracular hairs also differ. The strong and robust mouthhooks may explain the ability of larvae to penetrate deeply into human tissues. Perforated sieve plates covered with antler-like projections were observed within the anterior spiracles of the puparium of C. bezziana. The posterior spiracular discs each bear three spiracular slits with ≈2-μm wide openings that were viewed either open or closed by a membrane underneath. This study expands our knowledge of the fine details of the external morphology of both the third instar larva and puparium of C. bezziana, which is an obligatory myiasis-producing species in many regions. A key to differentiate the third instar of C. bezziana from other blow flies in Thailand is given.     

Genital myiasis by Wohlfahrtia magnifica (Diptera, Sarcophagidae) in Sicily (Italy)

Wohlfahrtia magnifica (Schiner, 1862; Diptera: Sarcophagidae), known also as flesh fly or screwworm, is a fly distributed especially in south Europe, Middle East, North Africa and China. Maggots of W. magnifica are responsible for traumatic myiasis in warm-blooded vertebrate animals and humans. In Italy data on wohlfahrtiosis in animals and humans are scant. This paper reports three cases of genital myiasis by W. magnifica in Sicily that occurred in a goat, a ram and a dog, respectively. Maggots were found in the vulva of a goat, in a wound localised in the scrotum of a ram and in the prepuce of a dog. Although the disease was not recorded before in the region, data collected from a questionnaire specifically designed for the study suggest that the disease is endemic in the area for more than 20 years. Larger epidemiological studies in the region are needed to get more data on disease prevalence and pattern of infestation as well as more information and education is needed for both farmers and veterinarians on wohlfahrtiosis and its strategies of control and treatment.     

Morphology of the first instar of the house fly Musca domestica (Diptera: Muscidae)

Scanning electron microscopy documentation of the first instar of Musca domestica L. is presented for the first time. The following morphological structures are documented: antenna, maxillary palpus, facial mask, spinulation, posterior spiracles, anal pad, and integumental micropores. Morphology of the first-instar larva of M. domestica is discussed in light of existing knowledge about early larval instars of Calyptrata flies.     

Wound myiasis in cattle infested by Lucilia caesar (Diptera: Calliphoridae)

A case report on facultative wound myiasis after sectio caesarea in a cow by larvae of Lucilia caesar in May 1986.     

Morphology of the puparia of the housefly, Musca domestica (Diptera: Muscidae) and blowfly, Chrysomya megacephala (Diptera: Calliphoridae)

Examination of the puparia of the housefly, Musca domestica L. and blowfly Chrysomya megacephala (F.), through scanning electron microscopy (SEM), revealed many differences in the profile of their morphology. Special attention was focused on puparial characteristics used to differentiate between the two fly species studied, and between other forensically important flies. Results of this study indicate that the housefly puparia are almost evenly rounded at both ends and the anterior spiracle bears six papillae. A pair of pupal respiratory horns is found laterally before the posterior boundary of the first abdominal segment, bearing numerous papillae that have a longitudinal opening along the oval convex base. The peritreme of each posterior spiracle forms a crude forward or reverse D-shape, encircling three sinuous slits. The blowfly pupariums anterior spiracle contains 8–12 papillae. The pupal respiratory horns protrude slightly and in some specimens a group of ~38 globules on the bubble-like membrane may be observed. Each of the posterior spiracles is more or less an oval- shaped peritreme, encircling three straight spiracular slits. The anatomical features presented herein allow for the differentiation of puparia of the two fly species studied and could prove useful in future forensic entomological assessments.     

Surface ultrastructure of the puparia of the blow fly, Lucilia cuprina (Diptera: Calliphoridae), and flesh fly, Liosarcophaga dux (Diptera: Sarcophagidae)

Surface ultrastructure of the puparia of the blow fly, Lucilia cuprina, and flesh fly, Liosarcophaga dux, are presented utilizing scanning electron microscopy (SEM). Emphasis was focused on characteristic features of the puparia that could be used for differentiation from other forensically important fly species. The puparium of L. cuprina typically measures 6.2±0.2 mm in length and 2.3±0.1 mm in width. Each anterior spiracle contains a single row of 5–7 papillae. The intersegmental spines between the prothorax and mesothorax are triangular with constricted tips. A clustered bubble membrane, comprising about 30 mammillate structures, is positioned dorsolaterally on each side of the first abdominal segment in young puparia but is replaced by short, tubular respiratory horns in aged puparia. The posterior end of the puparium is broadly truncate and bears a pair of medially positioned posterior spiracles that each contains three straight spiracular slits. The puparium of L. dux is larger in comparison to L. cuprina and typically measures 9.9±0.3 mm in length and 3.8±0.2 mm in width. An anterior spiracle of this species contains 14–17 papillae. The intersegmental spines between the prothorax and mesothorax are broad and triangular. A convoluted structure of unknown function was observed at the dorsolateral edge of segments 5–11. In L. dux, the caudal segment of the puparium is slightly tapered and abruptly truncated and contains a pair of posterior spiracles that are located within a deep concavity in the terminal end. Each posterior spiracular disc appears D-shaped, with a pronounced medial projection and three vertically oriented long, narrow spiracular slits. The anatomical features presented herein may be useful for identification of fly puparia of these two species in future forensic entomological investigations.     

Human auricular myiasis caused by Wohlfahrtia magnifica (Diptera: Sarcophagidae): about three observations in Morocco

We report three cases of human otomyiasis observed in rural Moroccan children. Myiasis of external orifices usually occurs from neglected chronic lesions of the patients with poor personal hygiene. The parasitologic identification revealed Wohlfahrtia magnifica. Wohlfahrtiosis is common myiasis of sheep and goats in Mediterranean basin. Through this paper we underline the epidemiological, pathogenic, clinical and therapeutic aspects of this parasitosis.     

Surface ultrastrucure of larva and puparia of blow fly Hypopygiopsis tumrasvini Kurahashi (Diptera: Calliphoridae)

Flies of the genus Hypopygiopsis are forensically important, as their larvae are found to associate with human corpses. In this study, the ultrastructure of larvae and puparia of Hypopygiopsis tumrasvini Kurahashi is presented using scanning electron microscopy (SEM). The larvae are vermiform-shaped, creamy white, and have a smooth integument. The pseudocephalon of larvae bears sensory structures, i.e., antenna, maxillary palpus, and ventral organ. Two tufts of fresh outgrowths (or cerri) were observed along the dorsal margin of the mouth opening of the first instar; whereas a strong mouth hook was apparent in the second and third instars. Keilin??s organ, the sensory structure, was noticeable on the ventral surface of the thoracic segments in all instars. In the second and third instars, six conspicuous tubercles were present along the peripheral rims of the last abdominal segment. The puparia were relatively large, measuring 7.77?C9.51?mm in length and 3.10?C3.97?mm in width. At the latero-dorsal edge of the first abdominal segment, a cluster of ??125 bubble membranes was seen in young puparia; whereas a minute pupal respiratory horn was observed in old one. An SEM image revealed antler-like projections lined within a chamber of a broken pupal respiratory horn. Comparison on number of the bubble membranes of the other blow fly species was shown and the role of pupal respiratory horn compared with other dipterans was discussed.     

Record of oral myiasis by Cochliomyia hominivorax (Diptera: Calliphoridae): case evidencing negligence in the treatment of incapable

Cases of myiasis in man associated with preexisting lesions are quite common. However, in the forensic field, certain behavioral habits related to insects may be useful to ratify mistreatment. This is a register of a case of oral myiasis by Cochliomyia hominivorax (Diptera: Calliphoridae), an obligate parasite of warm-blooded animals, in a 95-year-old man with Alzheimer's and Parkinson's disease. The identification of immatures removed (n?=?87) was based on their morphological characteristics. Considering the developmental time and length of the maggots, it was possible to estimate an infestation of at least 143 h. Undoubtedly, the poor state of health was one of the cofactors for the infestation; however, the long time of infestation observed denotes negligence in the conduct of patient care. In terms of prophylaxis, it would be recommended that individuals who need special care must have access to more comprehensive physical examinations and periodicals, as well as hygienic conditions should be meticulously observed. Additionally, the immatures causing myiasis after being removed must be stored and forwarded for analysis, since their identification can be crucial to determine the exact time and circumstances of an infestation, and consequently its pathogenesis. If we consider the aggressiveness of C. hominivorax, a fast and reliable diagnosis becomes even more important for an adequate treatment. Finally, it is expected that this study encourages the health care professionals to improve the treatment of incapable patients.     

Cordylobia anthropophaga (Diptera: Calliphoridae) outside Africa: a case of furuncular myiasis in a child returning from Congo

International travel to tropical countries accounts for an increasing incidence of imported diseases. An unusual case of furuncular myiasis due to Cordylobia anthropophaga (Blanchard) is reported in northern France in a 9-mo-old infant, after a 4-mo stay in Congo. A review has been made of the major cases of imported furuncular myiasis due to Cordylobia, as well as identification of second larval instars and management of the myiasis.     

Permeabilization of Cochliomyia hominivorax (Diptera: Calliphoridae) embryos

Embryos of the primary screwworm, Cochliomyia hominivorax (Coquerel), were successfully permeabilized for use in subsequent cryopreservation studies. Mortality was greater for eggs incubated for < 5 h before treatment. The mean survival of embryos to first instars was 55.7, 61.1, and 62.6% when the embryos were incubated for 5, 5.5, and 6 h before treatment, respectively. The survival to the pupal and adult stages was low. An improved media for culturing the embryos during and immediately after treatment needs to be devised and the procedure for rearing the larval stages also needs to be altered to improve survival for emerging adults.     

Morphology of immature stages of Hemipyrellia ligurriens (Wiedemann) (Diptera: Calliphoridae) for use in forensic entomology applications

In forensic investigations, all immature stages of flies (egg, larvae, and puparium) can serve as entomological evidence at death scenes. These insects are primarily used to estimate the post mortem interval (PMI), but can also be involved in the analysis of toxic substances, determining manner of death, and in indicating relocation of a corpse in homicide cases. In this study, we present the morphology of the egg, larvae, and puparium of Hemipyrellia ligurriens, a blow fly species of forensic importance in Thailand. Examination was conducted using scanning electron microscopy (SEM). The egg stage was found to display a relatively wide plastron region (or median hatch line area) that spans almost the entire length of the egg. The median hatch line is oriented in an upright position. External chorionic sculpture of the egg is present in a hexagonal pattern whose reticular boundaries are slightly elevated. In the larval stages, the most prominent morphological changes were detected upon comparison of the first to the second instar; whereas, the differences between second and third instar larvae were less obvious outside of the increase in number of posterior spiracular slits. Most of the major differences involve body size and structure of the anterior and posterior spiracles. Each anterior spiracle in both the second and third instars projects five to seven papillae apically. Each posterior spiracular disc of a third instar exhibits a complete peritreme, three spiracular slits, and a prominent button that is ventromedially located. The puparium is coarctate and features a clustered bubble membrane comprised of approximately 57 mammillate structures positioned dorsolaterally on each side of the first abdominal segment in young puparia. This feature is replaced by short, tubular respiratory horns in aged puparia. This study provides more detailed exposure of important morphological features that can be used for accurate identification of immature stages of H. ligurriens. Information presented can aid in forensic investigations involving this fly species.     

The first report of pigeon maggot, Protocalliphora sp. (Diptera: Calliphoridae) from domestic pigeons in Iran

Following the report of deaths in a few flocks of domestic pigeons in the Mazandaran province, Northern Iran, we conducted an investigation on the live and dead pigeons. We found reddish larvae on the skin of the pigeons and after close analysis of the mouthparts and spiracles; they were identified as second instar larvae of Protocalliphora sp. These blow fly larvae are obligate haematophagous parasites, highly pathogenic and cause high mortality in birds. Mortality in the infected flocks was approximately 25% and mainly among nestlings and young birds. Infected birds were treated with propoxur powder which was very effective, following which no additional mortalities or larvae were found. This is the first report of this myiasis agent in Iran.     

Nocturnal oviposition behavior of blow flies (Diptera: Calliphoridae)

It is widely held that blow flies, in general, and Phaenicia sericata (Meigen), in particular, are not active at night and do not lay eggs during that time. P. sericata is thought to require sunlight and warmth for oviposition. Three common and forensically important flies--Calliphora vicina (Robineau-Desvoidy), P. sericata, and Phormia regina (Meigen)--oviposited during the dark hours of the night during the summers of 1988 and 1989. Nocturnal oviposition can alter the usual estimate of the postmortem interval in homicide cases by as much as 12 h. Cases are presented that serve to change our concept of P. sericata from an obligate heliophile to a facultative heliophile that has a willingness to enter dim or dark places to oviposit.