Megaselia scalaris (Diptera: Phoridae) causing myiasis in Crotalus durissus terrificus (Serpentes: Viperidae) in Brazil

The scuttle flies (Diptera: Phoridae) of Iran with the description of Mahabadphora aesthesphora as a new genus and species

Scuttle flies (Diptera: Phoridae) are mega-diverse and often synanthropic insects that play superb roles in various ecosystems. Identification of this group of insects is challenging due to their small size, morphological identification difficulties, niche diversity, and lack of taxonomic keys. To pave the way, an in-depth investigation was directed toward the scuttle flies in Iran using morphological and molecular data. A dichotomous key was also developed to identify the genus and species of the phorids reported in the country. The faunistic findings revealed the presence of about 22,000 (13,903 male and 8,097 female) phorid materials organized into 11 genera. Megaselia species (n = 13768), made up about 99% of the specimens studied. Moreover, 71 morphologically defined species belonging to nine genera were molecularly characterized using COI, 28S rRNA, and Arginine kinase datasets. Excluding four Megaselia Rondani, 1856 species, our results specified that morphologically delimited species were in agreement with the molecular analyses inferred from the COI/28S rRNA and COI/Arginine kinase sequences with genetic distances and phylogenetic trees. According to the results of the present study and previously published data, the Phoridae recorded for Iran are a total of 97 species that are ordered in 13 genera and three subfamilies, including Chonocephalinae, Metopininae and Phorinae. By comparing the known world phorid genera, a new monotypic genus of scuttle flies, Mahabadphora aesthesphora gen. nov., sp. nov., was identified based on its morphological and molecular characteristics and included in an updated key. Our results could comprehensively determine the taxonomic status of scuttle flies in Iran, scrutinize their phylogenetic structures and facilitate their identification.

High morbidity cutaneous enzootic myiasis by Dermatobia hominis (Diptera: Oestridae) in sambar deer (Rusa unicolor)

This study describes the first known occurrence and treatment of enzootic cutaneous myiasis by Dermatobia hominis in a herd of sambar deer (Rusa unicolor). Sambar deer are clinically affected by enzootic cutaneous myiasis during the spring and summer in Rio de Janeiro, Brazil. Through direct inspection and clinicopathological evaluation in the herd with 80 R. unicolor, it was observed that infestation by D. hominis caused 100% morbidity. At histological exam, skin had eosinophilic and granulomatous chronic active severe necrohemorrhagic dermatitis associated with botfly and moderate surrounding fibroplasia. The systemic treatment with oral ivermectin at 0.08% was effective in 93.7% of deer with enzootic cutaneous myiasis after fourteen days. After treatment, the skin deer had eosinophilic and granulomatous chronic severe dermatitis associated with degenerated botfly and severe fibroplasia. Notable differences in leukocyte profile were observed between groups pre- and post-treatment. Decrease of relative values of neutrophils and eosinophils were significant in the treated deer group. An increase of relative values of monocytes was also confirmed in the treated group. Sambar deer was the only species affected by D. hominis, even though several other wild herbivores were kept in the same area. More studies are needed to elucidate the susceptibility of R. unicolor to D. hominis cutaneous infestations.

DEPREDACION POR INSECTOS DE NIDOS Y NEONATOS PROTEGIDOS DE PODOCNEMIS VOGLI (SABANAS INUNDABLES DEL CASANARE)

La galápaga sabanera(Podocnemis vogli) es una tortuga de ambientes acuáticos, principalmente lénticos, que centra su época reproductiva en la temporada seca, en la que sus huevos son una importante fuente de alimento en la red trófica y para el hombre, de manera que frecuentemente son afectados por depredadores naturales. Con el propósito de reducir el efecto negativo de la depredación natural sobre las nidadas de P vogli en la Reserva Natural de la Sociedad Civil La Esperanza en Paz de Ariporo, se implementó una estrategia de protección directa con malla metálica y se realizó el seguimiento a las posturas durante tres periodos de anidación entre 2016 y 2018. Como resultado del uso de esta estrategia para proteger las nidadas, se evidenció el efecto de otros depredadores y parásitos menos conspicuos como las hormigas legionarias (Labidus) y las larvas de moscas parasitarias (Phoridae). En ambos casos la afectación se registró en los neonatos recién eclosionados de galápaga sabanera al interior de los nidos, algunos de ellos hallados en un estado de salud precaria o muertos. Este es el primer reporte de depredación de los neonatos de P. vogli por estas especies de insectos sobre las cuales las estrategias físicas convencionales de protección fueron ineficientes.

A review on the occurrence of Cochliomyia hominivorax (Diptera: Calliphoridae) in Brazil

Cochliomyia hominivorax (Coquerel, 1858), the New World screwworm, causes primary myiasis in wild and domestic animals in tropical and subtropical regions of Brazil. Although this species is considered to occur throughout the country, organized information about its recorded distribution has not been available until now. This article aimed to provide a comprehensive review of the historical and current data published on both immature (myiasis) and adult stages of C. hominivorax in Brazil. A total of 174 articles were found; of these, 141 articles reported myiasis cases in cattle (146 records), humans (68 records), and other mammalian hosts (40 records), and captures of adult flies were reported in 33 articles. C. hominivorax is widespread in Brazil, having been recorded in 208 municipalities in all major biomes of the country.

Developmental Variation of Indian Thermophilic Variety of Scuttle Fly Megaselia (Megaselia) scalaris (Loew, 1866) (Diptera: Phoridae) on Different Substrates

The scuttle flies (Diptera: Phoridae) are important in forensic dipterology, because of their necrophagous habit. They are amongst the first wave of insects visiting human corpses in mechanically barricaded environments; hence their immature stages are generally used for estimation of PMI. The effect of different substrates commonly used for developmental studies was studied to analyze the variation of growth of the thermophilic variety of Megaselia (M.) scalaris prevalent in India on GDM, EDM, and SMS (n = 3). One approach of PMI estimation depends on larvae collected from the crime scene and comparing them with reference data derived from larval rearing to establish PMI. Results showed that there was a significant variation in avg. length (F(2,111) = 15.79873, p = 0.000000917), width (F(2,111) = 14.60528, p = 0.00000234), and biomass (F(2,111) = 37.01727, p = 0.000000000000482) of the immature stages in the three media and the larvae grow maximally in the SMS medium. The results of the present study thus provide baseline data on the growth and developmental pattern of the Megaselia (M.) scalaris, which can be utilized in conjunction with specific geoclimatic reference data, for forensic entomological studies and also for using the phorid as a biocontrol agent of pestiferous insects.

The complete mitochondrial genome of the scuttle fly, Megaselia scalaris (Diptera: Phoridae)

More than 1400 scuttle flies species in worldwide comprise the Megaselia genus, the largest genus in the family Phoridae. The complete mitochondrial genome of Megaselia scalaris, a medically important entomology was sequenced for the first time. The 15,599 bp circular genome contains the 37 genes found in a typical Metazoan genome: 13 protein-coding genes, 22 transfer RNA genes and 2 ribosomal RNA genes. The mitochondrial genome also contains one non-coding A + T-rich region. The arrangement of the genes was identical with other insect. Each of the base composition on heavy strand was as follows A: 38.87%, G: 13.74%, C: 9.46%, T: 37.93% and the A + T content 76.80%. The mitochondrial genome of M. scalaris presented may be valuable for determining phylogenetic relationships within the order Diptera and especially for the family Phoridae. These sequences could also be used to select reliable molecular markers for species identification in forensic entomology.

A case study of Megaselia scalaris (Diptera: Phoridae) causing ocular myiasis in a western hognose snake

Late instar larvae of the scuttle fly, Megaselia scalaris Loew, were found near the right eye of a live captive-reared western hognose snake, Heterodon nasicus Baird and Girard. Dissection and removal of the snake's dorsal cranial bones revealed tissue degradation of the infected eye, the optic nerve, and the brain case; we suggest that these factors contributed to the death of this snake. This case study further demonstrates the opportunistic behavior of M. scalaris.

Bioactivity of latex from Euphorbia splendens var. hislopii (Euphorbiaceae) on post-embryonic development of Megaselia scalaris (Phoridae)

Larvae of Megaselia scalaris (Loew, 1866) feed on a wide range of decomposing organic matter and present a great importance to public health. This study evaluated the effect of crude latex extract from Euphorbia splendens var. hislopii (Euphorbiaceae) on post-embryonic development time of M. scalaris under laboratory conditions. The latex was used in its crude lyophilized form, dissolved in distilled water and tested in concentrations of 5 microg/mL, 10 microg/mL and 20 microg/mL. The latex was applied with the aid of an automatic pipette (1 microL/larva) on the newly-hatched larvae. Each group (the three concentrations of latex and the control group) was composed of 50 larvae and fed with 25mg of decomposing horse flesh. The experiment was made in quadruplicate. The observations were recorded daily. The data were submitted to analysis of variance (ANOVA) and Tukey's post hoc-test with a 5% significance level. The post-embryonic development time for all stages (larval, pupal and newly-hatched larvae to adult) tested with all three latex concentrations was significantly shorter than for the control group, but without any significant difference among the different concentrations. The more sensitive stages to the substance were pupal and newly-hatched larvae to adult. The viability was less than 51.5% in the three concentrations of latex in these stages and they were lower than for the control group (67.4% for pupal stage and 64% for newly-hatched larvae to adult). Therefore, it is likely that this substance has influence on the development and viability of these flies and can become a promising agent for insect pest management.

A laboratory-based study for first documented case of urinary myiasis caused by larvae of Megaselia scalaris (Diptera: Phoridae) in Saudi Arabia

Megaselia scalaris (Diptera: Phoridae) is one of the medically important insects. Maggots from a urine sample of a 5-year-old Saudi girl were examined microscopically for identification. These maggots were cultured to become adult flies. Larvae and adults were identified using standard keys. Protozoan flagellates were obtained from the gut of the larvae. This is the first report of M. scalaris as a causative agent of urinary human myiasis in Saudi Arabia.

Natural history of the scuttle fly, Megaselia scalaris

The larvae of Megaselia scalaris (Diptera: Phoridae) exploit a broad spectrum of larval pabula. Consequently, the species features in a range of situations that affect the resources or well-being of humans. Furthermore, M. scalaris is readily cultured in the laboratory and is therefore favored as an experimental species for genetic, developmental, and bioassay studies. However, the extensive but widely scattered literature, reviewed herein, is frequently ignored by specialists, which gives rise to the unwitting repetition of previous work as well as insupportable proposals.